KSZ8021RNL / KSZ8031RNL 10Base-T/100Base-TX PHY with RMII Support General Description Features The KSZ8031RNL is a single-supply 10Base-T/100Base* Single-chip 10Base-T/100Base-TX IEEE 802.3 TX Ethernet physical layer transceiver for transmission compliant Ethernet Transceiver and reception of data over standard CAT-5 unshielded * RMII v1.2 Interface support with 50MHz reference clock twisted pair (UTP) cable. output to MAC, and option to input 50MHz reference The KSZ8031RNL is a highly-integrated, compact solution. clock It reduces board cost and simplifies board layout by using * RMII back-to-back mode support for 100Mbps copper on-chip termination resistors for the differential pairs, by repeater or media converter integrating a low noise regulator to supply the 1.2V core, * MDC/MDIO Management Interface for PHY register and by offering 1.8/2.5/3.3V digital I/O interface support. configuration The KSZ8031RNL offers the Reduced Media Independent * Programmable interrupt output Interface (RMII) for direct connection to RMII-compliant * LED outputs for link and activity status indication MACs in Ethernet processors and switches. * On-chip termination resistors for the differential pairs As the power-up default, the KSZ8031RNL uses a 25MHz * Baseline Wander Correction crystal to generate all required clocks, including the 50MHz RMII reference clock output for the MAC. The * HP Auto MDI/MDI-X for reliable detection and KSZ8021RNL is the version that takes in the 50MHz RMII correction for straight-through and crossover cables reference clock as the power-up default. with disable and enable option To facilitate system bring-up and debugging in production * Auto-negotiation to automatically select the highest linktesting and in product deployment, parametric NAND tree up speed (10/100 Mbps) and duplex (half/full) support enables fault detection between KSZ8031RNL * Power down and power saving modes (R) I/Os and board, while Micrel's LinkMD TDR-based cable * LinkMD(R) TDR-based cable diagnostics for identification diagnostics permit identification of faulty copper cabling. of faulty copper cabling The KSZ8031RNL and KSZ8021RNL are available in 24* Parametric NAND Tree support for fault detection pin, lead-free QFN packages (see Ordering Information). between chip I/Os and board Data sheets and support documentation can be found on Micrel's web site at: www.micrel.com. ____________________________________________________________________________________________________________ Functional Diagram LinkMD is a registered trademark of Micrel, Inc. Micrel Inc. * 2180 Fortune Drive * San Jose, CA 95131 * USA * tel +1 (408) 944-0800 * fax + 1 (408) 474-1000 * http://www.micrel.com August 2010 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL More Features Applications * Loopback modes for diagnostics * Single 3.3V power supply with VDD I/O options for 1.8V, 2.5V, or 3.3V * Built-in 1.2V regulator for core * Available in 24-pin (4mm x 4mm) QFN package * * * * * * Game Console IP Phone IP Set-top Box IP TV LOM Printer Ordering Information Part Number Temperature Range Package Lead Finish KSZ8021RNL 0C to 70C 24-Pin QFN Pb-Free RMII with 50MHz clock input (power-up default), Commercial Temperature -40C to 85C 24-Pin QFN Pb-Free RMII with 50MHz clock input (power-up default), Industrial Temperature 0C to 70C 24-Pin QFN Pb-Free RMII with 25MHz crystal/clock input and 50MHz RMII REF_CLK output (power-up default), Commercial Temperature -40C to 85C 24-Pin QFN Pb-Free RMII with 25MHz crystal/clock input and 50MHz RMII REF_CLK output (power-up default), Industrial Temperature KSZ8021RNLI (1) KSZ8031RNL KSZ8031RNLI (1) Description Note: 1. Contact factory for lead time. August 2010 2 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Revision History Revision Date Summary of Changes 1.0 8/16/10 Data sheet created. August 2010 3 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Contents General Description .............................................................................................................................................................. 1 Features ................................................................................................................................................................................. 1 Functional Diagram............................................................................................................................................................... 1 Applications........................................................................................................................................................................... 2 Ordering Information ............................................................................................................................................................ 2 Revision History.................................................................................................................................................................... 3 Contents................................................................................................................................................................................. 4 List of Figures........................................................................................................................................................................ 6 List of Tables ......................................................................................................................................................................... 7 Pin Configuration - KSZ8021RNL / KSZ8031RNL.............................................................................................................. 8 Pin Description - KSZ8021RNL / KSZ8031RNL ................................................................................................................. 9 Strapping Options - KSZ8021RNL / KSZ8031RNL .......................................................................................................... 11 Functional Description: 10Base-T/100Base-TX Transceiver ......................................................................................... 12 100Base-TX Transmit....................................................................................................................................................... 12 100Base-TX Receive........................................................................................................................................................ 12 10Base-T Transmit ........................................................................................................................................................... 12 10Base-T Receive ............................................................................................................................................................ 13 Scrambler/De-scrambler (100Base-TX only).................................................................................................................... 13 PLL Clock Synthesizer...................................................................................................................................................... 13 Auto-Negotiation ............................................................................................................................................................... 13 RMII Data Interface.............................................................................................................................................................. 15 RMII Signal Definition ....................................................................................................................................................... 15 Reference Clock (REF_CLK) ....................................................................................................................................... 15 Transmit Enable (TXEN) .............................................................................................................................................. 15 Transmit Data [1:0] (TXD[1:0]) ..................................................................................................................................... 15 Carrier Sense/Receive Data Valid (CRS_DV).............................................................................................................. 15 Receive Data [1:0] (RXD[1:0]) ...................................................................................................................................... 16 Receive Error (RXER) .................................................................................................................................................. 16 Collision Detection........................................................................................................................................................ 16 RMII Signal Diagram - for KSZ8021/31RNL...................................................................................................................... 16 RMII - 25MHz Clock Mode............................................................................................................................................... 16 RMII - 50MHz Clock Mode............................................................................................................................................... 17 Back-to-Back Mode - 100Mbps Copper Repeater / Media Converter............................................................................ 18 RMII Back-to-Back Mode.................................................................................................................................................. 18 MII Management (MIIM) Interface....................................................................................................................................... 19 Interrupt (INTRP) ................................................................................................................................................................. 19 HP Auto MDI/MDI-X ............................................................................................................................................................. 19 Straight Cable ................................................................................................................................................................... 20 Crossover Cable ............................................................................................................................................................... 20 LinkMD(R) Cable Diagnostics................................................................................................................................................ 21 August 2010 4 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL NAND Tree Support ............................................................................................................................................................ 21 NAND Tree I/O Testing..................................................................................................................................................... 22 Power Management ............................................................................................................................................................ 22 Power Saving Mode.......................................................................................................................................................... 22 Energy Detect Power Down Mode ................................................................................................................................... 22 Power Down Mode ........................................................................................................................................................... 22 Slow Oscillator Mode ........................................................................................................................................................ 23 Reference Circuit for Power and Ground Connections .................................................................................................. 23 Register Map........................................................................................................................................................................ 24 Register Description ........................................................................................................................................................... 24 Register Description (Continued)...................................................................................................................................... 25 Register Description (Continued)...................................................................................................................................... 26 Register Description (Continued)...................................................................................................................................... 27 Register Description (Continued)...................................................................................................................................... 28 Register Description (Continued)...................................................................................................................................... 29 Register Description (Continued)...................................................................................................................................... 30 Register Description (Continued)...................................................................................................................................... 31 Register Description (Continued)...................................................................................................................................... 32 Absolute Maximum Ratings(1) ............................................................................................................................................ 33 Operating Ratings(2) ............................................................................................................................................................ 33 Electrical Characteristics(3) ................................................................................................................................................ 33 Electrical Characteristics(3) (Continued) ........................................................................................................................... 34 Timing Diagrams ................................................................................................................................................................. 35 RMII Timing....................................................................................................................................................................... 35 Auto-Negotiation Timing ................................................................................................................................................... 36 MDC/MDIO Timing ........................................................................................................................................................... 37 Reset Timing..................................................................................................................................................................... 38 Reset Circuit ........................................................................................................................................................................ 39 Reference Circuit for LED Strapping Pin.......................................................................................................................... 40 Magnetics Specification ..................................................................................................................................................... 41 Reference Clock - Connection and Selection.................................................................................................................. 41 Package Information........................................................................................................................................................... 43 August 2010 5 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL List of Figures Figure 1. Auto-Negotiation Flow Chart................................................................................................................................. 14 Figure 2. KSZ8021/31RNL RMII Interface (RMII - 25MHz Clock Mode) ............................................................................ 16 Figure 3. KSZ8021/31RNL RMII Interface (RMII - 50MHz Clock Mode) ............................................................................ 17 Figure 4. KSZ8021/31RNL and KSZ8041FTL RMII Back-to-Back Media Converter .......................................................... 18 Figure 5. Typical Straight Cable Connection ....................................................................................................................... 20 Figure 6. Typical Crossover Cable Connection ................................................................................................................... 20 Figure 7. KSZ8021/31RNL Power and Ground Connections .............................................................................................. 23 Figure 8. RMII Timing - Data Received from RMII .............................................................................................................. 35 Figure 9. RMII Timing - Data Input to RMII ......................................................................................................................... 35 Figure 10. Auto-Negotiation Fast Link Pulse (FLP) Timing ................................................................................................. 36 Figure 11. MDC/MDIO Timing.............................................................................................................................................. 37 Figure 12. Reset Timing....................................................................................................................................................... 38 Figure 13. Recommended Reset Circuit.............................................................................................................................. 39 Figure 14. Recommended Reset Circuit for interfacing with CPU/FPGA Reset Output...................................................... 39 Figure 15. Reference Circuits for LED Strapping Pin .......................................................................................................... 40 Figure 16. 25MHz Crystal / Oscillator Reference Clock Connection ................................................................................... 41 Figure 17. 50MHz Oscillator Reference Clock Connection ................................................................................................. 42 August 2010 6 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL List of Tables Table 1. RMII Signal Description.......................................................................................................................................... 15 Table 2. RMII Signal Connection for RMII Back-to-Back Mode (100Base-TX Copper Repeater) ...................................... 18 Table 3. MII Management Frame Format - for KSZ8021/31RNL........................................................................................ 19 Table 4. MDI/MDI-X Pin Definition ....................................................................................................................................... 20 Table 5. NAND Tree Test Pin Order - for KSZ8021/31RNL ............................................................................................... 21 Table 6. KSZ8021/31RNL Power Pin Description ............................................................................................................... 23 Table 7. RMII Timing Parameters - KSZ8021/31RNL (25MHz input to XI pin, 50MHz output from REF_CLK pin)........... 35 Table 8. RMII Timing Parameters - KSZ8021/31RNL (50MHz input to XI pin)................................................................... 35 Table 9. Auto-Negotiation Fast Link Pulse (FLP) Timing Parameters ................................................................................. 36 Table 10. MDC/MDIO Timing Parameters ........................................................................................................................... 37 Table 11. Reset Timing Parameters .................................................................................................................................... 38 Table 12. Magnetics Selection Criteria ................................................................................................................................ 41 Table 13. Qualified Single Port 10/100 Magnetics............................................................................................................... 41 Table 14. 25MHz Crystal / Reference Clock Selection Criteria ........................................................................................... 42 Table 15. 50MHz Oscillator / Reference Clock Selection Criteria ....................................................................................... 42 August 2010 7 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Pin Configuration - KSZ8021RNL / KSZ8031RNL 24-Pin (4mm x 4mm) QFN August 2010 8 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Pin Description - KSZ8021RNL / KSZ8031RNL (1) Pin Function Pin Number Pin Name 1 VDD_1.2 P 2 VDDA_3.3 P 3 RXM I/O Physical receive or transmit signal (- differential) Type 1.2V core VDD (power supplied by KSZ8021RNL / KSZ8031RNL) Decouple with 2.2uF and 0.1uF capacitors-to-ground. 3.3V analog VDD. 4 RXP I/O Physical receive or transmit signal (+ differential) 5 TXM I/O Physical transmit or receive signal (- differential) 6 TXP I/O Physical transmit or receive signal (+ differential) 7 XO O Crystal feedback - for 25 MHz crystal This pin is a no connect if oscillator or external clock source is used. RMII - 25MHz Mode: 25MHz +/-50ppm Crystal / Oscillator / External Clock Input RMII - 50MHz Mode: 50MHz +/-50ppm Oscillator / External Clock Input For unmanaged mode (power-up default setting), 8 XI I KSZ8021RNL takes in the 50MHz clock on this pin. KSZ8031RNL takes in the 25MHz crystal / clock on this pin. After power-up, both the KSZ8021RNL and KSZ8031RNL can be programmed via PHY register 1Fh bit [7] to either the 25MHz mode or 50MHz mode. See also REF_CLK (pin 16) description. 9 REXT I Set physical transmit output current Connect a 6.49K resistor-to-ground on this pin. Management Interface (MII) Data I/O 10 MDIO I/O 11 MDC I 12 RXD1 Ipd/O RMII Receive Data Output[1] 13 RXD0 Ipu/O RMII Receive Data Output[0] 14 VDDIO P 15 CRS_DV / PHYAD[1:0] Ipd/O This pin has a weak pull-up, is open drain like, and requires an external 1.0K pullup resistor. Management Interface (MII) Clock Input This clock pin is synchronous to the MDIO data pin. (2) (2) 3.3V, 2.5V or 1.8V digital VDD RMII Mode: Carrier Sense/Receive Data Valid Output / Config Mode: The pull-up/pull-down value is latched as PHYAD[1:0] at the de-assertion of reset. See "Strapping Options" section for details. RMII - 25MHz Mode: This pin provides the 50MHz RMII reference clock output to the MAC. RMII - 50MHz Mode: This pin is a no connect. For unmanaged mode (power-up default setting), 16 REF_CLK Ipd/O KSZ8021RNL is in RMII - 50MHz mode and does not use this pin. KSZ8031RNL is in RMII - 25MHz mode and outputs the 50MHz RMII reference clock on this pin. After power-up, both KSZ8021RNL and KSZ8031RNL can be programmed via PHY register 1Fh bit [7] to either 25MHz mode or 50MHz mode. See also XI (pin 8) description. 17 RXER Ipd/O 18 INTRP Ipu/Opu RMII Receive Error Output Interrupt Output: Programmable Interrupt Output August 2010 This pin has a weak pull-up, is open drain like, and requires an external 1.0K pullup resistor. 9 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Pin Description - KSZ8021RNL / KSZ8031RNL (Continued) (1) Pin Function Pin Number Pin Name 19 TXEN I RMII Transmit Enable Input 20 TXD0 I RMII Transmit Data Input[0] 21 TXD1 I/O 22 GND Gnd Type (3) (3) RMII Transmit Data Input[1] NAND Tree Mode: NAND Tree output pin Ground LED Output: Programmable LED0 Output / Config Mode: Latched as Auto-Negotiation Enable (register 0h, bit [12]) and SPEED (register 0h, bit [13]) at the de-assertion of reset. See "Strapping Options" section for details. The LED0 pin is programmable via register 1Fh bits [5:4], and is defined as follows. LED mode = [00] Link/Activity 23 LED0 / ANEN_SPEED Ipu/O Pin State LED Definition No Link High OFF Link Low ON Activity Toggle Blinking Link Pin State LED Definition No Link High OFF Link Low ON LED mode = [01] LED mode = [10], [11] 24 RST# I PADDLE GND Gnd Reserved Chip Reset (active low) Ground Notes: 1. P = Power supply. Gnd = Ground. I = Input. O = Output. I/O = Bi-directional. Ipu/O = Input with internal pull-up (see Electrical Characteristics for value) during power-up/reset; output pin otherwise. Ipd/O = Input with internal pull-down (see Electrical Characteristics for value) during power-up/reset; output pin otherwise. Ipu/Opu = Input with internal pull-up (see Electrical Characteristics for value) during power-up/reset; output pin with internal pull-up (see Electrical Characteristics for value) otherwise. 2. RMII Rx Mode: The RXD[1:0] bits are synchronous with the 50MHz RMII Reference Clock. For each clock period in which CRS_DV is asserted, two bits of recovered data are sent by the PHY to the MAC. 3. RMII Tx Mode: The TXD[1:0] bits are synchronous with the 50MHz RMII Reference Clock . For each clock period in which TXEN is asserted, two bits of data are received by the PHY from the MAC. August 2010 10 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Strapping Options - KSZ8021RNL / KSZ8031RNL Pin Number Pin Name (1) Type Pin Function The PHY Address is latched at the de-assertion of reset and is configurable to either one of the following two values: 15 PHYAD[1:0] Ipd/O Pull-up = PHY Address is set to 00011b (0x3h) Pull-down (default) = PHY Address is set to 00000b (0x0h) PHY Address bits [4:2] are set to `000' by default. Auto-Negotiation Enable and SPEED mode Pull-up (default) = Enable Auto-Negotiation and set 100Mbps Speed 23 ANEN_SPEED Ipu/O Pull-down = Disable Auto-Negotiation and set 10Mbps Speed At the de-assertion of reset, this pin value is latched into register 0h bit [12] for Autonegotiation enable/disable, register 0h bit [13] for the Speed select, and register 4h (Auto-Negotiation Advertisement) for the Speed capability support. Note: 1. Ipu/O = Input with internal pull-up (see Electrical Characteristics for value) during power-up/reset; output pin otherwise. Ipd/O = Input with internal pull-down (see Electrical Characteristics for value) during power-up/reset; output pin otherwise. The PHYAD[1:0] strap-in pin is latched at the de-assertion of reset. In some systems, the RMII MAC receive input pin may drive high/low during power-up or reset, and consequently cause the PHYAD[1:0] strap-in pin, a shared pin with the RMII CRS_DV signal, to be latched to the unintended high/low states. In this case, an external pull-up (4.7K) or pull-down (1.0K) should be added on the PHYAD[1:0] strap-in pin to ensure the intended value is strapped-in correctly. August 2010 11 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Functional Description: 10Base-T/100Base-TX Transceiver The KSZ8031RNL is an integrated single 3.3V supply Fast Ethernet transceiver. It is fully compliant with the IEEE 802.3 Specification. It reduces board cost and simplifies board layout by using on-chip termination resistors for the two differential pairs and by integrating the regulator to supply the 1.2V core. On the copper media side, the KSZ8031RNL supports 10Base-T and 100Base-TX for transmission and reception of data over a standard CAT-5 unshielded twisted pair (UTP) cable, and HP auto MDI/MDI-X for reliable detection of and correction for straight-through and crossover cables. On the MAC side, the KSZ8031RNL provides the Reduced Media Independent Interface (RMII) for direct connection with RMII-compliant Ethernet MAC processors and switches. The MII management bus option gives the MAC processor complete access to the KSZ8031RNL control and status registers. Additionally, an interrupt pin eliminates the need for the processor to poll for PHY status change. As the power-up default, the KSZ8031RNL uses a 25MHz crystal to generate all required clocks, including the 50MHz RMII reference clock output for the MAC. The KSZ8021RNL is the version which takes in the 50MHz RMII reference clock as the power-up default. The KSZ8021/31RNL is used to refer to both KSZ8021RNL and KSZ8031RNL versions in this data sheet. 100Base-TX Transmit The 100Base-TX transmit function performs parallel-to-serial conversion, 4B/5B encoding, scrambling, NRZ-to-NRZI conversion, and MLT3 encoding and transmission. The circuitry starts with a parallel-to-serial conversion, which converts the MII data from the MAC into a 125MHz serial bit stream. The data and control stream is then converted into 4B/5B coding and followed by a scrambler. The serialized data is further converted from NRZ-to-NRZI format, and then transmitted in MLT3 current output. The output current is set by an external 6.49k 1% resistor for the 1:1 transformer ratio. The output signal has a typical rise/fall time of 4ns and complies with the ANSI TP-PMD standard regarding amplitude balance, overshoot, and timing jitter. The wave-shaped 10Base-T output is also incorporated into the 100Base-TX transmitter. 100Base-TX Receive The 100Base-TX receiver function performs adaptive equalization, DC restoration, MLT3-to-NRZI conversion, data and clock recovery, NRZI-to-NRZ conversion, de-scrambling, 4B/5B decoding, and serial-to-parallel conversion. The receiving side starts with the equalization filter to compensate for inter-symbol interference (ISI) over the twisted pair cable. Since the amplitude loss and phase distortion is a function of the cable length, the equalizer must adjust its characteristics to optimize performance. In this design, the variable equalizer makes an initial estimation based upon comparisons of incoming signal strength against some known cable characteristics, and then tunes itself for optimization. This is an ongoing process and self-adjusts against environmental changes such as temperature variations. Next, the equalized signal goes through a DC restoration and data conversion block. The DC restoration circuit is used to compensate for the effect of baseline wander and to improve the dynamic range. The differential data conversion circuit converts the MLT3 format back to NRZI. The slicing threshold is also adaptive. The clock recovery circuit extracts the 125MHz clock from the edges of the NRZI signal. This recovered clock is then used to convert the NRZI signal into the NRZ format. This signal is sent through the de-scrambler followed by the 4B/5B decoder. Finally, the NRZ serial data is converted to the MII format and provided as the input data to the MAC. 10Base-T Transmit The 10Base-T drivers are incorporated with the 100Base-TX drivers to allow for transmission using the same magnetic. The drivers perform internal wave-shaping and pre-emphasis, and output 10Base-T signals with a typical amplitude of 2.5V peak. The 10Base-T signals have harmonic contents that are at least 27dB below the fundamental frequency when driven by an all-ones Manchester-encoded signal. August 2010 12 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL 10Base-T Receive On the receive side, input buffer and level detecting squelch circuits are employed. A differential input receiver circuit and a PLL performs the decoding function. The Manchester-encoded data stream is separated into clock signal and NRZ data. A squelch circuit rejects signals with levels less than 400 mV or with short pulse widths to prevent noise at the RXP and RXM inputs from falsely triggering the decoder. When the input exceeds the squelch limit, the PLL locks onto the incoming signal and the KSZ8021/31RNL decodes a data frame. The receive clock is kept active during idle periods in between data reception. Scrambler/De-Scrambler (100Base-TX Only) The scrambler is used to spread the power spectrum of the transmitted signal to reduce EMI and baseline wander, and the de-scrambler is needed to recover the scrambled signal. PLL Clock Synthesizer The KSZ8021/31RNL in RMII - 25MHz Clock Mode generates all internal clocks and all external clocks for system timing from an external 25MHz crystal, oscillator, or reference clock. For the KSZ8021/31RNL in RMII - 50MHz Clock Mode, these clocks are generated from an external 50MHz oscillator or system clock. Auto-Negotiation The KSZ8021/31RNL conforms to the auto-negotiation protocol, defined in Clause 28 of the IEEE 802.3 Specification. Auto-negotiation allows UTP (Unshielded Twisted Pair) link partners to select the highest common mode of operation. During auto-negotiation, link partners advertise capabilities across the UTP link to each other, and then compare their own capabilities with those they received from their link partners. The highest speed and duplex setting that is common to the two link partners is selected as the mode of operation. The following list shows the speed and duplex operation mode from highest to lowest priority. * Priority 1: 100Base-TX, full-duplex * Priority 2: 100Base-TX, half-duplex * Priority 3: 10Base-T, full-duplex * Priority 4: 10Base-T, half-duplex If auto-negotiation is not supported or the KSZ8021/31RNL link partner is forced to bypass auto-negotiation, then the KSZ8021/31RNL sets its operating mode by observing the signal at its receiver. This is known as parallel detection, and allows the KSZ8021/31RNL to establish link by listening for a fixed signal protocol in the absence of auto-negotiation advertisement protocol. Auto-negotiation is enabled by either hardware pin strapping (ANEN_SPEED, pin 23) or software (register 0h, bit [12]). By default, auto-negotiation is enabled after power-up or hardware reset. Afterwards, auto-negotiation can be enabled or disabled by register 0h, bit [12]. If auto-negotiation is disabled, the speed is set by register 0h, bit [13], and the duplex is set by register 0h, bit [8]. The auto-negotiation link up process is shown in Figure 1. August 2010 13 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Figure 1. Auto-Negotiation Flow Chart August 2010 14 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL RMII Data Interface The Reduced Media Independent Interface (RMII) specifies a low pin count Media Independent Interface (MII). It provides a common interface between physical layer and MAC layer devices, and has the following key characteristics: * Pin count is 8 pins (3 pins for data transmission, 4 pins for data reception, 1 pin for the 50MHz reference clock). * 10Mbps and 100Mbps data rates are supported at both half and full duplex. * Data transmission and reception are independent and belong to separate signal groups. * Transmit data and receive data are each 2-bit wide, a dibit. RMII Signal Definition The following table describes the RMII signals. Refer to RMII Specification v1.2 for detailed information. RMII Signal Name Direction (with respect to PHY, KSZ8021/31RNL signal) Direction (with respect to MAC) Output (25MHz Clock Mode) / REF_CLK <no connect> (50MHz Clock Mode) Input / Description Input or <no connect> Synchronous 50MHz reference clock for receive, transmit and control interface TXEN Input Output Transmit Enable TXD[1:0] Input Output Transmit Data [1:0] CRS_DV Output Input Carrier Sense/Receive Data Valid RXD[1:0] Output Input Receive Data [1:0] RXER Output Input, or (not required) Receive Error Table 1. RMII Signal Description Reference Clock (REF_CLK) REF_CLK is a continuous 50MHz clock that provides the timing reference for TXEN, TXD[1:0], CRS_DV, RXD[1:0], and RXER. For RMII - 25MHz Clock Mode, the KSZ8021/31RNL generates and outputs the 50MHz RMII REF_CLK to the MAC at REF_CLK (Pin 16). For RMII - 50MHz Clock Mode, the KSZ8021/31RNL takes in the 50MHz RMII REF_CLK from the MAC or system board at XI (Pin 8) and has the REF_CLK (pin 16) left as a no connect. Transmit Enable (TXEN) TXEN indicates that the MAC is presenting dibits on TXD[1:0] for transmission. It is asserted synchronously with the first dibit of the preamble and remains asserted while all dibits to be transmitted are presented on the RMII, and is negated prior to the first REF_CLK following the final dibit of a frame. TXEN transitions synchronously with respect to REF_CLK. Transmit Data [1:0] (TXD[1:0]) TXD[1:0] transitions synchronously with respect to REF_CLK. When TXEN is asserted, TXD[1:0] are accepted for transmission by the PHY. TXD[1:0] is "00" to indicate idle when TXEN is de-asserted. Values other than "00" on TXD[1:0] while TXEN is de-asserted are ignored by the PHY. Carrier Sense/Receive Data Valid (CRS_DV) CRS_DV is asserted by the PHY when the receive medium is non-idle. It is asserted asynchronously on detection of carrier. This is when squelch is passed in 10Mbps mode, and when two non-contiguous zeroes in 10 bits are detected in 100Mbps mode. Loss of carrier results in the de-assertion of CRS_DV. August 2010 15 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL So long as carrier detection criteria are met, CRS_DV remains asserted continuously from the first recovered dibit of the frame through the final recovered dibit, and it is negated prior to the first REF_CLK that follows the final dibit. The data on RXD[1:0] is considered valid once CRS_DV is asserted. However, since the assertion of CRS_DV is asynchronous relative to REF_CLK, the data on RXD[1:0] is "00" until proper receive signal decoding takes place. Receive Data [1:0] (RXD[1:0]) RXD[1:0] transitions synchronously with respect to REF_CLK. For each clock period in which CRS_DV is asserted, RXD[1:0] transfers two bits of recovered data from the PHY. RXD[1:0] is "00" to indicate idle when CRS_DV is de-asserted. Values other than "00" on RXD[1:0] while CRS_DV is deasserted are ignored by the MAC. Receive Error (RXER) RXER is asserted for one or more REF_CLK periods to indicate that a Symbol Error (e.g., a coding error that a PHY is capable of detecting, and that may otherwise be undetectable by the MAC sub-layer) was detected somewhere in the frame presently being transferred from the PHY. RXER transitions synchronously with respect to REF_CLK. While CRS_DV is de-asserted, RXER has no effect on the MAC. Collision Detection The MAC regenerates the COL signal of the MII from TXEN and CRS_DV. RMII Signal Diagram - for KSZ8021/31RNL The KSZ8021/31RNL RMII pin connections to the MAC are shown in the following figures for RMII - 25MHz Clock Mode and RMII - 50MHz Clock Mode. RMII - 25MHz Clock Mode The KSZ8031RNL is configured to RMII - 25MHz Clock Mode after it is powered up or hardware reset with the following: * A 25MHz crystal connected to XI, XO (Pins 8, 7), or an external 25MHz clock source (oscillator) connected to XI The KSZ8021RNL is configured optionally to RMII - 25MHz Clock Mode after it is powered up or hardware reset and software programmed with the following: * A 25MHz crystal connected to XI, XO (pins 8, 7), or an external 25MHz clock source (oscillator) connected to XI * Register 1Fh, bit [7] programmed to `0' to select RMII - 25MHz Clock Mode Figure 2. KSZ8021/31RNL RMII Interface (RMII - 25MHz Clock Mode) August 2010 16 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL RMII - 50MHz Clock Mode The KSZ8021RNL is configured to RMII - 50MHz Clock Mode after it is powered up or hardware reset with the following: * An external 50MHz clock source (oscillator) connected to XI (Pin 8) The KSZ8031RNL is configured optionally to RMII - 50MHz Clock Mode after it is powered up or hardware reset and software programmed with the following: * An external 50MHz clock source (oscillator) connected to XI (Pin 8) * Register 1Fh, bit [7] programmed to `1' to select RMII - 50MHz Clock Mode Figure 3. KSZ8021/31RNL RMII Interface (RMII - 50MHz Clock Mode) August 2010 17 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Back-to-Back Mode - 100Mbps Copper Repeater / Media Converter Two KSZ8021/31RNL devices can be connected back-to-back to form a managed 100Base-TX copper repeater. A KSZ8021/31RNL and a KSZ8041FTL can be connected back-to-back to provide a managed media converter solution. Media conversion is between 100Base-TX copper and 100Base-FX fiber. On the copper side, link up at 10Base-T is not allowed, and is blocked during auto-negotiation. Figure 4. KSZ8021/31RNL and KSZ8041FTL RMII Back-to-Back Media Converter RMII Back-to-Back Mode In RMII Back-to-Back mode, a KSZ8021/31RNL interfaces with another KSZ8021/31RNL, or a KSZ8041FTL to provide a 100Mbps copper repeater, or media converter solution, respectively. The KSZ8021/31RNL devices are configured to RMII Back-to-Back mode after they are powered up or hardware reset and software programmed with the following: * A common 50MHz reference clock connected to XI (Pin 8) * Register 1Fh, bit [7] programmed to `1' to select RMII - 50MHz Clock Mode for KSZ8031RNL (KSZ8021RNL is set to RMII - 50MHz Clock Mode as the default after power up or hardware reset) * Register 16h, bits [6] and [1] programmed to `1' and `1', respectively, to enable RMII Back-to-Back mode. * RMII signals connected as shown in the following table. KSZ8021/31RNL (100Base-TX copper) KSZ8021/31RNL (100Base-TX copper) [Device 1] [Device 2] Pin Name Pin Number Pin Type Pin Name Pin Number Pin Type CRS_DV 15 Output TXEN 19 Input RXD1 12 Output TXD1 21 Input RXD0 13 Output TXD0 20 Input TXEN 19 Input CRS_DV 15 Output TXD1 21 Input RXD1 12 Output TXD0 20 Input RXD0 13 Output Table 2. RMII Signal Connection for RMII Back-to-Back Mode (100Base-TX Copper Repeater) August 2010 18 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL MII Management (MIIM) Interface The KSZ8021/31RNL supports the IEEE 802.3 MII Management Interface, also known as the Management Data Input / Output (MDIO) Interface. This interface enables upper-layer device, like a MAC processor, to monitor and control the state of the KSZ8021/31RNL. An external device with MIIM capability is used to read the PHY status and/or configure the PHY settings. Further details on the MIIM interface can be found in Clause 22.2.4 of the IEEE 802.3 Specification. The MIIM interface consists of the following: * A physical connection that incorporates the clock line (MDC) and the data line (MDIO). * A specific protocol that operates across the aforementioned physical connection that allows the external controller to communicate with one or more PHY devices. * A set of 16-bit MDIO registers. Registers [0:8] are standard registers, and their functions are defined per the IEEE 802.3 Specification. The additional registers are provided for expanded functionality. See "Register Map" section for details. The KSZ8021/31RNL supports only two unique PHY addresses, 0x0h and 0x3h. The PHYAD[1:0] strapping pin is used to select either 0x0h or 0x3h as the unique PHY address for the KSZ8021/31RNL device. Table 3 shows the MII Management frame format for the KSZ8021/31RNL. Preamble Start of Frame Read/Write Read 32 1's 01 10 Write 32 1's 01 01 OP Code PHY REG Address Address Bits [4:0] Bits [4:0] 000AA RRRRR Z0 DDDDDDDD_DDDDDDDD Z 000AA RRRRR 10 DDDDDDDD_DDDDDDDD Z TA Data Idle Bits [15:0] Table 3. MII Management Frame Format - for KSZ8021/31RNL Interrupt (INTRP) The INTRP (pin 18) is an optional interrupt signal that is used to inform the external controller that there has been a status update to the KSZ8021/31RNL PHY register. Register 1Bh, bits [15:8] are the interrupt control bits to enable and disable the conditions for asserting the INTRP signal. Register 1Bh, bits [7:0] are the interrupt status bits to indicate which interrupt conditions have occurred. The interrupt status bits are cleared after reading register 1Bh. Register 1Fh, bit 9 sets the interrupt level to active high or active low. The default is active low. The MII management bus option gives the MAC processor complete access to the KSZ8021/31RNL control and status registers. Additionally, an interrupt pin eliminates the need for the processor to poll the PHY for status change. HP Auto MDI/MDI-X The HP Auto MDI/MDI-X configuration eliminates the confusion of whether to use a straight cable or a crossover cable between the KSZ8021/31RNL and its link partner. This feature allows the KSZ8021/31RNL to use either type of cable to connect with a link partner that is in either MDI or MDI-X mode. The auto-sense function detects transmit and receive pairs from the link partner, and then assigns transmit and receive pairs of the KSZ8021/31RNL accordingly. HP Auto MDI/MDI-X is enabled by default. It is disabled by writing a one to register 1Fh, bit [13]. MDI and MDI-X mode is selected by register 1Fh, bit [14] if HP Auto MDI/MDI-X is disabled. An isolation transformer with symmetrical transmit and receive data paths is recommended to support auto MDI/MDI-X. The IEEE 802.3 Standard defines MDI and MDI-X in Table 4. August 2010 19 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL MDI MDI-X RJ-45 Pin Signal RJ-45 Pin Signal 1 TX+ 1 RX+ 2 TX- 2 RX- 3 RX+ 3 TX+ 6 RX- 6 TX- Table 4. MDI/MDI-X Pin Definition Straight Cable A straight cable connects a MDI device to a MDI-X device, or a MDI-X device to a MDI device. Figure 5 depicts a typical straight cable connection between a NIC card (MDI) and a switch, or hub (MDI-X). Figure 5. Typical Straight Cable Connection Crossover Cable A crossover cable connects a MDI device to another MDI device, or a MDI-X device to another MDI-X device. Figure 6 depicts a typical crossover cable connection between two switches or hubs (two MDI-X devices). Figure 6. Typical Crossover Cable Connection August 2010 20 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL LinkMD(R) Cable Diagnostics The LinkMD(R) function utilizes time domain reflectometry (TDR) to analyze the cabling plant for common cabling problems, such as open circuits, short circuits and impedance mismatches. LinkMD(R) works by sending a pulse of known amplitude and duration down the MDI or MDI-X pair, and then analyzing the shape of the reflected signal to determine the type of fault. The time duration for the reflected signal to return provides the approximate distance to the cabling fault. The LinkMD(R) function processes this TDR information and presents it as a numerical value that can be translated to a cable distance. LinkMD(R) is initiated by accessing register 1Dh, the LinkMD(R) Control/Status Register, in conjunction with register 1Fh, the PHY Control 2 Register. The latter register is used to disable auto MDI/MDI-X and to select either MDI or MDI-X as the cable differential pair for testing. NAND Tree Support The KSZ8021/31RNL provides parametric NAND tree support for fault detection between chip I/Os and board. The NAND tree is a chain of nested NAND gates in which each KSZ8021/31RNL digital I/O (NAND tree input) pin is an input to one NAND gate along the chain. At the end of the chain, the TXD1 pin provides the output for the nested NAND gates. The NAND tree test process includes: * Enabling NAND tree mode * Pulling all NAND tree input pins high * Driving low each NAND tree input pin sequentially per the NAND tree pin order * Checking the NAND tree output to ensure there is a toggle high-to-low or low-to-high for each NAND tree input driven low Table 5 lists the NAND tree pin order. Pin Number Pin Name NAND Tree Description 10 MDIO Input 11 MDC Input 12 RXD1 Input 13 RXD0 Input 15 CRS_DV Input 16 REF_CLK Input 17 RXER Input 18 INTRP Input 19 TXEN Input 20 TXD0 Input 23 LED0 Input 21 TXD1 Output Table 5. NAND Tree Test Pin Order - for KSZ8021/31RNL August 2010 21 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL NAND Tree I/O Testing The following procedure can be used to check for faults on the KSZ8021/31RNL digital I/O pin connections to the board: 1. Enable NAND tree mode by setting register 16h, bit [5] to `1'. 2. Use board logic to drive all KSZ8021/31RNL NAND tree input pins high. 3. Use board logic to drive each NAND tree input pin, per KSZ8021/31RNL NAND Tree pin order, as follow: a. Toggle the first pin (MDIO) from high to low, and verify the TXD1 pin switch from low to high to indicate that the first pin is connected properly. b. Leave the first pin (MDIO) low. c. Toggle the second pin (MDC) from high to low, and verify the TXD1 pin switch from high to low to indicate that the second pin is connected properly. d. Leave the first pin (MDIO) and the second pin (MDC) low. e. Toggle the third pin from high to low, and verify the TXD1 pin switch from low to high to indicate that the third pin is connected properly. f. Continue with this sequence until all KSZ8021/31RNL NAND tree input pins have been toggled. Each KSZ8021/31RNL NAND tree input pin must cause the TXD1 output pin to toggle high-to-low or low-to-high to indicate a good connection. If the TXD1 pin fails to toggle when the KSZ8021/31RNL input pin toggles from high to low, then the input pin has a fault. Power Management The KSZ8021/31RNL offers the following power management modes: Power Saving Mode Power Saving Mode is used to reduce the transceiver power consumption when the cable is unplugged. It is enabled by writing a one to register 1Fh, bit [10], and is in effect when auto-negotiation mode is enabled and cable is disconnected (no link). In this mode, the KSZ8021/31RNL turns off all transceiver blocks, except for transmitter, energy detect and PLL circuits. By default, Power Saving Mode is disabled after power-up. Energy Detect Power Down Mode Energy Detect Power Down (EDPD) Mode is used to further reduce the transceiver power consumption when the cable is un-plugged. It is enabled by writing a zero to register 18h, bit [11], and is in effect when auto-negotiation mode is enabled and cable is disconnected (no link). EDPD Mode works in conjunction with PLL off (set by writing a one to register 10h, bit [4] to turn PLL off automatically in EDPD Mode) to turn off all KSZ8021/31RNL transceiver blocks, except for transmitter and energy detect circuits. Further power consumption is achieved by extending the time interval in between transmissions of link pulses to check for the presence of a link partner. The periodic transmission of link pulses is needed to ensure two link partners in the same low power state and with auto MDI/MDI-X disabled can wake up when the cable is connected between them. By default, Energy Detect Power Down Mode is disabled after power-up. Power Down Mode Power Down Mode is used to power down the KSZ8021/31RNL device when it is not in use after power-up. It is enabled by writing a one to register 0h, bit [11]. In this mode, the KSZ8021/31RNL disables all internal functions, except for the MII management interface. The KSZ8021/31RNL exits (disables) Power Down Mode after register 0h, bit [11] is set back to zero. August 2010 22 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Slow Oscillator Mode Slow Oscillator Mode is used to disconnect the input reference crystal/clock on XI (pin 8) and select the on-chip slow oscillator when the KSZ8021/31RNL device is not in use after power-up. It is enabled by writing a one to register 11h, bit [5]. Slow Oscillator Mode works in conjunction with Power Down Mode to put the KSZ8021/31RNL device in the lowest power state with all internal functions disabled, except for the MII management interface. To properly exit this mode and return to normal PHY operation, use the following programming sequence: 1. Disable Slow Oscillator Mode by writing a zero to register 11h, bit [5]. 2. Disable Power Down Mode by writing a zero to register 0h, bit [11]. 3. Initiate software reset by writing a one to register 0h, bit [15]. Reference Circuit for Power and Ground Connections The KSZ8021/31RNL is a single 3.3V supply device with a built-in regulator to supply the 1.2V core. The power and ground connections are shown in Figure 7 and Table 6 for 3.3V VDDIO. Figure 7. KSZ8021/31RNL Power and Ground Connections Power Pin Pin Number VDD_1.2 1 VDDA_3.3 2 VDDIO 14 Description Decouple with 2.2uF and 0.1uF capacitors-to-ground. Connect to board's 3.3V supply through ferrite bead. Decouple with 22uF and 0.1uF capacitors-to-ground. Connect to board's 3.3V supply for 3.3V VDDIO. Decouple with 22uF and 0.1uF capacitors-to-ground. Table 6. KSZ8021/31RNL Power Pin Description August 2010 23 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Register Map Register Number (Hex) Description 0h Basic Control 1h Basic Status 2h PHY Identifier 1 3h PHY Identifier 2 4h Auto-Negotiation Advertisement 5h Auto-Negotiation Link Partner Ability 6h Auto-Negotiation Expansion 7h Auto-Negotiation Next Page 8h Link Partner Next Page Ability 9h Reserved 10h Digital Reserved Control 11h AFE Control 1 12h - 14h 15h Reserved RXER Counter 16h Operation Mode Strap Override 17h Operation Mode Strap Status 18h Expanded Control 19h - 1Ah Reserved 1Bh Interrupt Control/Status 1Ch Reserved 1Dh LinkMD(R) Control/Status 1Eh PHY Control 1 1Fh PHY Control 2 Register Description Address Name (1) Description Mode Default RW/SC 0 RW 0 Register 0h - Basic Control 1 = Software reset 0.15 Reset 0 = Normal operation This bit is self-cleared after a `1' is written to it. 0.14 Loop-back 1 = Loop-back mode 0 = Normal operation 1 = 100Mbps 0.13 Speed Select 0.12 AutoNegotiation Enable August 2010 0 = 10Mbps This bit is ignored if auto-negotiation is enabled (register 0.12 = 1). RW 1 = Enable auto-negotiation process 0 = Disable auto-negotiation process If enabled, auto-negotiation result overrides settings in register 0.13 and 0.8. 24 RW Set by ANEN_SPEED strapping pin. See "Strapping Options" section for details. Set by ANEN_SPEED strapping pin. See "Strapping Options" section for details. M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Register Description (Continued) Address Name (1) Description Mode Default RW 0 RW 0 RW/SC 0 Register 0h - Basic Control 1 = Power down mode 0 = Normal operation 0.11 Power Down 0.10 Isolate 0.9 Restart AutoNegotiation 0.8 Duplex Mode 0.7 Collision Test 0.6:0 Reserved If software reset (register 0.15) is used to exit Power Down mode (register 0.11 = 1), two software reset writes (register 0.15 = 1) are required. First write clears Power Down mode; second write resets chip and re-latches the pin strapping pin values. 1 = Electrical isolation of PHY from MII 0 = Normal operation 1 = Restart auto-negotiation process 0 = Normal operation. This bit is self-cleared after a `1' is written to it. 1 = Full-duplex RW 0 = Half-duplex 1 = Enable COL test 0 = Disable COL test 1 RW 0 RO 000_0000 RO 0 RO 1 RO 1 RO 1 RO 1 RO 000_0 RO 1 RO 0 RO/LH 0 RO 1 Register 1h - Basic Status 1 = T4 capable 1.15 100Base-T4 1.14 100Base-TX Full Duplex 1 = Capable of 100Mbps full-duplex 1.13 100Base-TX Half Duplex 1 = Capable of 100Mbps half-duplex 1.12 10Base-T Full Duplex 1 = Capable of 10Mbps full-duplex 1.11 10Base-T Half Duplex 1 = Capable of 10Mbps half-duplex 1.10:7 Reserved 1.6 No Preamble 1.5 AutoNegotiation Complete 1.4 Remote Fault 1.3 AutoNegotiation Ability August 2010 0 = Not T4 capable 0 = Not capable of 100Mbps full-duplex 0 = Not capable of 100Mbps half-duplex 0 = Not capable of 10Mbps full-duplex 0 = Not capable of 10Mbps half-duplex 1 = Preamble suppression 0 = Normal preamble 1 = Auto-negotiation process completed 0 = Auto-negotiation process not completed 1 = Remote fault 0 = No remote fault 1 = Capable to perform auto-negotiation 0 = Not capable to perform auto-negotiation 25 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Register Description (Continued) Address Name 1.2 Link Status 1.1 Jabber Detect 1.0 Extended Capability (1) Mode Default RO/LL 0 RO/LH 0 1 = Supports extended capabilities registers RO 1 Assigned to the 3rd through 18th bits of the Organizationally Unique Identifier (OUI). Kendin Communication's OUI is 0010A1 (hex) RO 0022h Assigned to the 19th through 24th bits of the Organizationally Unique Identifier (OUI). Kendin Communication's OUI is 0010A1 (hex) RO 0001_01 Six bit manufacturer's model number RO 01_0101 Four bit manufacturer's revision number RO Indicates silicon revision RW 0 RO 0 RW 0 RO 0 RW 00 RO 0 Description 1 = Link is up 0 = Link is down 1 = Jabber detected 0 = Jabber not detected (default is low) Register 2h - PHY Identifier 1 2.15:0 PHY ID Number Register 3h - PHY Identifier 2 3.15:10 PHY ID Number 3.9:4 Model Number 3.3:0 Revision Number Register 4h - Auto-Negotiation Advertisement 4.15 Next Page 4.14 Reserved 4.13 Remote Fault 4.12 Reserved 1 = Next page capable 0 = No next page capability. 1 = Remote fault supported 0 = No remote fault [00] = No PAUSE 4.11:10 Pause [10] = Asymmetric PAUSE [01] = Symmetric PAUSE [11] = Asymmetric & Symmetric PAUSE 1 = T4 capable 4.9 100Base-T4 4.8 100Base-TX Full-Duplex 1 = 100Mbps full-duplex capable 4.7 100Base-TX Half-Duplex 1 = 100Mbps half-duplex capable 4.6 10Base-T Full-Duplex 1 = 10Mbps full-duplex capable 4.5 10Base-T Half-Duplex 1 = 10Mbps half-duplex capable 4.4:0 Selector Field August 2010 0 = No T4 capability 0 = No 100Mbps full-duplex capability 0 = No 100Mbps half-duplex capability 0 = No 10Mbps full-duplex capability 0 = No 10Mbps half-duplex capability [00001] = IEEE 802.3 26 RW RW Set by ANEN_SPEED strapping pin. See "Strapping Options" section for details. Set by ANEN_SPEED strapping pin. See "Strapping Options" section for details. RW 1 RW 1 RW 0_0001 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Register Description (Continued) Address Name (1) Description Mode Default RO 0 RO 0 RO 0 RO 0 RO 00 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0_0001 RO 0000_0000_000 RO/LH 0 RO 0 RO 1 RO/LH 0 RO 0 Register 5h - Auto-Negotiation Link Partner Ability 5.15 Next Page 5.14 Acknowledge 5.13 Remote Fault 5.12 Reserved 1 = Next page capable 0 = No next page capability 1 = Link code word received from partner 0 = Link code word not yet received 1 = Remote fault detected 0 = No remote fault [00] = No PAUSE 5.11:10 Pause [10] = Asymmetric PAUSE [01] = Symmetric PAUSE [11] = Asymmetric & Symmetric PAUSE 1 = T4 capable 5.9 100Base-T4 5.8 100Base-TX Full-Duplex 1 = 100Mbps full-duplex capable 5.7 100Base-TX Half-Duplex 1 = 100Mbps half-duplex capable 5.6 10Base-T Full-Duplex 1 = 10Mbps full-duplex capable 5.5 10Base-T Half-Duplex 1 = 10Mbps half-duplex capable 5.4:0 Selector Field 0 = No T4 capability 0 = No 100Mbps full-duplex capability 0 = No 100Mbps half-duplex capability 0 = No 10Mbps full-duplex capability 0 = No 10Mbps half-duplex capability [00001] = IEEE 802.3 Register 6h - Auto-Negotiation Expansion 6.15:5 Reserved 6.4 Parallel Detection Fault 6.3 Link Partner Next Page Able 6.2 Next Page Able 6.1 Page Received 6.0 Link Partner AutoNegotiation Able August 2010 1 = Fault detected by parallel detection 0 = No fault detected by parallel detection 1 = Link partner has next page capability 0 = Link partner does not have next page capability 1 = Local device has next page capability 0 = Local device does not have next page capability 1 = New page received 0 = New page not received yet 1 = Link partner has auto-negotiation capability 0 = Link partner does not have auto-negotiation capability 27 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Register Description (Continued) Address Name (1) Description Mode Default RW 0 RO 0 RW 1 RW 0 RO 0 RW 000_0000_0001 RO 0 RO 0 RO 0 RO 0 RO 0 RO 000_0000_0000 RW 0000_0000_000 RW 0 RW 0000 RW 0000_0000_00 RW 0 RW 0_0000 Register 7h - Auto-Negotiation Next Page 7.15 Next Page 7.14 Reserved 7.13 Message Page 7.12 Acknowledge2 7.11 Toggle 1 = Additional next page(s) will follow 0 = Last page 1 = Message page 0 = Unformatted page 1 = Will comply with message 0 = Cannot comply with message 1 = Previous value of the transmitted link code word equaled logic one 0 = Logic zero 7.10:0 Message Field 11-bit wide field to encode 2048 messages Register 8h - Link Partner Next Page Ability 8.15 Next Page 8.14 Acknowledge 8.13 Message Page 8.12 Acknowledge2 8.11 Toggle 8.10:0 Message Field 1 = Additional Next Page(s) will follow 0 = Last page 1 = Successful receipt of link word 0 = No successful receipt of link word 1 = Message page 0 = Unformatted page 1 = Able to act on the information 0 = Not able to act on the information 1 = Previous value of transmitted link code word equal to logic zero 0 = Previous value of transmitted link code word equal to logic one Register 10h - Digital Reserved Control 10.15:5 Reserved 1 = Turn PLL off automatically in EDPD mode. 10.4 PLL off 0 = Keep PLL on in EDPD mode. See also register 18h, bit [11] for EDPD mode. 10.3:0 Reserved Register 11h - AFE Control 1 11.15:6 11.5 Reserved Slow Oscillator Mode Enable Slow Oscillator Mode is used to disconnect the input reference crystal/clock on the XI pin and select the on-chip slow oscillator when the KSZ8021/31RNL device is not in use after power-up. 1 = Enable 0 = Disable This bit automatically sets software power down to the analog side when enabled. 11.4:0 August 2010 Reserved 28 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Register Description (Continued) Address Name (1) Description Mode Default Receive error counter for Symbol Error frames RO/SC 0000h Register 15h - RXER Counter 15.15:0 RXER Counter Register 16h - Operation Mode Strap Override 16.15:11 Reserved RW 0000_0 16.10 Reserved RO 0 16.9:7 Reserved RW 00_0 16.6 RMII B-to-B override 1 = Override strap-in for RMII Back-to-Back mode (set also bit 1 of this register to 1) RW 0 16.5 NAND Tree override 1 = Override strap-in for NAND Tree mode RW 0 16.4:2 Reserved RW 0_00 16.1 RMII override 16.0 Reserved 1 = Override strap-in for RMII mode RW 1 RW 0 Register 17h - Operation Mode Strap Status [000] = Strap to PHY Address 0 17.15:13 PHYAD[2:0] strap-in status 17.12:2 Reserved 17.1 RMII strap-in status 17.0 Reserved [011] = Strap to PHY Address 3 The KSZ8021/31RNL supports only PHY addresses 0x0h and 0x3h only. RO RO 1 = Strap to RMII mode RO RO Register 18h - Expanded Control 18.15:12 Reserved RW 0000 RW 1 RW 000_0000_0000 RW 0 RW 0 RW 0 RW 0 Energy Detect Power Down (EDPD) mode 18.11 EDPD Disabled 1 = Disable 0 = Enable See also register 10h, bit [4] for PLL off. 18.10:0 Reserved Register 1Bh - Interrupt Control/Status 1b.15 Jabber Interrupt Enable 1b.14 Receive Error Interrupt Enable 1b.13 Page Received Interrupt Enable 1 = Enable Page Received Interrupt 1b.12 Parallel Detect Fault Interrupt Enable 1 = Enable Parallel Detect Fault Interrupt August 2010 1 = Enable Jabber Interrupt 0 = Disable Jabber Interrupt 1 = Enable Receive Error Interrupt 0 = Disable Receive Error Interrupt 0 = Disable Page Received Interrupt 0 = Disable Parallel Detect Fault Interrupt 29 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Register Description (Continued) (1) Address Name Description 1b.11 Link Partner Acknowledge Interrupt Enable 1b.10 Link Down Interrupt Enable 1b.9 Remote Fault Interrupt Enable 1b.8 Link Up Interrupt Enable 1 = Enable Link Up Interrupt 1b.7 Jabber Interrupt 1 = Jabber occurred 1b.6 Receive Error Interrupt 1 = Receive Error occurred 1b.5 Page Receive Interrupt 1 = Page Receive occurred 1b.4 Parallel Detect Fault Interrupt 1 = Parallel Detect Fault occurred 1b.3 Link Partner Acknowledge Interrupt 1 = Link Partner Acknowledge occurred 1b.2 Link Down Interrupt 1b.1 Remote Fault Interrupt 1b.0 Link Up Interrupt Mode Default RW 0 RW 0 RW 0 RW 0 RO/SC 0 RO/SC 0 RO/SC 0 RO/SC 0 RO/SC 0 RO/SC 0 RO/SC 0 RO/SC 0 RW/SC 0 RO 00 RO 0 RW 000 RO 0_0000_0000 1 = Enable Link Partner Acknowledge Interrupt 0 = Disable Link Partner Acknowledge Interrupt 1= Enable Link Down Interrupt 0 = Disable Link Down Interrupt 1 = Enable Remote Fault Interrupt 0 = Disable Remote Fault Interrupt 0 = Disable Link Up Interrupt 0 = Jabber did not occurred 0 = Receive Error did not occurred 0 = Page Receive did not occur 0 = Parallel Detect Fault did not occur 0 = Link Partner Acknowledge did not occur 1 = Link Down occurred 0 = Link Down did not occur 1 = Remote Fault occurred 0 = Remote Fault did not occur 1 = Link Up occurred 0 = Link Up did not occur Register 1Dh - LinkMD(R) Control/Status 1d.15 Cable Diagnostic Test Enable 1 = Enable cable diagnostic test. After test has completed, this bit is self-cleared. 0 = Indicates cable diagnostic test (if enabled) has completed and the status information is valid for read. [00] = normal condition 1d.14:13 Cable Diagnostic Test Result 1d.12 Short Cable Indicator 1d.11:9 Reserved 1d.8:0 Cable Fault Counter [01] = open condition has been detected in cable [10] = short condition has been detected in cable [11] = cable diagnostic test has failed August 2010 1 = Short cable (<10 meter) has been detected by LinkMD(R). Distance to fault 30 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Register Description (Continued) Address Name (1) Description Mode Default RO 0000_00 RO 0 RO 0 Register 1Eh - PHY Control 1 1e.15:10 Reserved 1e.9 Enable Pause (Flow Control) 1e.8 Link Status 1e.7 Polarity Status 1e.6 Reserved 1e.5 MDI/MDI-X State 1e.4 Energy Detect 1e.3 PHY Isolate 1 = Flow control capable 0 = No flow control capability 1 = Link is up 0 = Link is down 1 = Polarity is reversed RO 0 = Polarity is not reversed RO 1 = MDI-X 0 RO 0 = MDI 1 = Presence of signal on receive differential pair 0 = No signal detected on receive differential pair 1 = PHY in isolate mode 0 = PHY in normal operation RO 0 RW 0 RO 000 RW 1 RW 0 RW 0 RW 0 RW 0 [000] = still in auto-negotiation [001] = 10Base-T half-duplex [010] = 100Base-TX half-duplex 1e.2:0 Operation Mode Indication [011] = reserved [100] = reserved [101] = 10Base-T full-duplex [110] = 100Base-TX full-duplex [111] = reserved Register 1Fh - PHY Control 2 1f:15 HP_MDIX 1 = HP Auto MDI/MDI-X mode 0 = Micrel Auto MDI/MDI-X mode When Auto MDI/MDI-X is disabled, 1 = MDI-X Mode 1f:14 MDI/MDI-X Select Transmit on RXP,RXM (pins 4,3) and Receive on TXP,TXM (pins 6,5) 0 = MDI Mode Transmit on TXP,TXM (pins 6,5) and Receive on RXP,RXM (pins 4,3) 1f:13 Pair Swap Disable 1f.12 Reserved 1 = Disable auto MDI/MDI-X 0 = Enable auto MDI/MDI-X 1 = Force link pass 0 = Normal link operation 1f.11 August 2010 Force Link This bit bypasses the control logic and allow transmitter to send pattern even if there is no link. 31 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Register Description (Continued) Address Name 1f.10 Power Saving 1f.9 Interrupt Level 1f.8 Enable Jabber 1f.7 RMII Reference Clock Select 1f.6 Reserved 1f.5:4 LED mode (1) Description 1 = Enable power saving 0 = Disable power saving 1 = Interrupt pin active high 0 = Interrupt pin active low 1 = Enable jabber counter 0 = Disable jabber counter 1 = RMII - 50MHz Clock Mode; clock input to XI (pin 8) is 50MHz 0 = RMII - 25MHz Clock Mode; clock input to XI (pin 8) is 25MHz [00] = LED0 : Link/Activity [01] = LED0 : Link Mode Default RW 0 RW 0 RW 1 RW 1 (for KSZ8021RNL) 0 (for KSZ8031RNL) RW 0 RW 00 RW 0 RW 0 RW 0 RW 0 [10], [11] = Reserved Disable 1 = Disable transmitter Transmitter 0 = Enable transmitter 1f.2 Remote Loop-back 1 = Remote (analog) loop back is enable 1f.1 Reserved 1f.0 Disable Data Scrambling 1f.3 0 = Normal mode 1 = Disable scrambler 0 = Enable scrambler Note: 1. RW = Read/Write. RO = Read only. SC = Self-cleared. LH = Latch high. LL = Latch low. August 2010 32 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Absolute Maximum Ratings(1) Operating Ratings(2) Supply Voltage (VDD_1.2) .................................................. -0.5V to +1.8V (VDDIO, VDDA_3.3) ....................................... -0.5V to +4.0V Input Voltage (all inputs) .............................. -0.5V to +4.0V Output Voltage (all outputs) ......................... -0.5V to +4.0V Lead Temperature (soldering, 10sec.)....................... 260C Storage Temperature (Ts) .........................-55C to +150C Supply Voltage (VDDIO_3.3, VDDA_3.3) .......................... +3.135V to +3.465V (VDDIO_2.5)........................................ +2.375V to +2.625V (VDDIO_1.8)........................................ +1.710V to +1.890V Ambient Temperature (TA , Commercial)...................................... 0C to +70C (TA , Industrial) ...................................... -40C to +85C Maximum Junction Temperature (TJ Max) ................. 125C Thermal Resistance (JA) ....................................49.22C/W Thermal Resistance (JC) ....................................25.65C/W Electrical Characteristics(3) Symbol Parameter Supply Current (VDDIO,VDDA_3.3 = 3.3V) Condition Min. Typ. Max. Units (4) IDD1 10Base-T Full-Duplex Traffic @ 100% Utilization 45 mA IDD2 100Base-TX Full-Duplex Traffic @ 100% Utilization 49 mA IDD3 Power Saving Mode Ethernet Cable Disconnected (reg. 1F.10 = 1) 30 mA IDD4 Power Down Mode Software Power Down (reg. 0.11 = 1) 3.0 mA CMOS Level Inputs VIH VIL IIN Input High Voltage Input Low Voltage Input Current VDDIO = 3.3V 2.0 VDDIO = 2.5V 1.8 VDDIO = 1.8V 1.3 V VDDIO = 3.3V 0.8 VDDIO = 2.5V 0.7 VDDIO = 1.8V 0.5 VIN = GND ~ VDDIO -10 10 V A CMOS Level Outputs VOH VOL |Ioz| Output High Voltage Output Low Voltage VDDIO = 3.3V 2.4 VDDIO = 2.5V 2.0 VDDIO = 1.8V 1.5 V VDDIO = 3.3V 0.4 VDDIO = 2.5V 0.4 VDDIO = 1.8V 0.3 Output Tri-State Leakage 10 V A LED Output ILED Output Drive Current LED0 pin 8 mA Strapping Pins pu pd August 2010 Internal Pull-Up Resistance Internal Pull-Down Resistance VDDIO = 3.3V 29 43 76 VDDIO = 2.5V 37 59 102 VDDIO = 1.8V 57 100 187 VDDIO = 3.3V 27 43 76 VDDIO = 2.5V 35 60 110 VDDIO = 1.8V 55 100 190 33 K K M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Electrical Characteristics(3) (Continued) Symbol Parameter Condition Min. Typ. Max. Units 1.05 V 2 % 100Base-TX Transmit (measured differentially after 1:1 transformer) VO Peak Differential Output Voltage 100 Termination Across Differential Output VIMB Output Voltage Imbalance 100 Termination Across Differential Output tr, tf 0.95 Rise/Fall Time 3 5 Rise/Fall Time Imbalance 0 0.5 Duty-Cycle Distortion + 0.25 Overshoot VSET 5 Reference Voltage of ISET Output Jitter ns V 0.65 Peak-to-Peak 0.7 % 1.4 ns 2.8 V 3.5 ns 10Base-T Transmit (measured differentially after 1:1 transformer) VP tr, tf Peak Differential Output Voltage 100 Termination Across Differential Output Jitter Added Peak-to-Peak Rise/Fall Time 2.2 25 ns 400 mV 600 ps 10Base-T Receive VSQ Squelch Threshold 5MHz Square Wave REF_CLK Output 50MHz RMII Clock Output Jitter Peak-to-Peak (Applies to RMII - 50MHz Clock Mode only) Notes: 1. Exceeding the absolute maximum rating may damage the device. Stresses greater than the absolute maximum rating may cause permanent damage to the device. Operation of the device at these or any other conditions above those specified in the operating sections of this specification is not implied. Maximum conditions for extended periods may affect reliability. 2. The device is not guaranteed to function outside its operating rating. 3. TA = 25C. Specification is for packaged product only. 4. Current consumption is for the single 3.3V supply KSZ8021/31RNL device only, and includes the transmit driver current and the 1.2V supply voltage (VDD_1.2) that are supplied by the KSZ8021/31RNL. August 2010 34 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Timing Diagrams RMII Timing Figure 8. RMII Timing - Data Received from RMII Figure 9. RMII Timing - Data Input to RMII Timing Parameter Description Min. Typ. Max. tcyc Clock cycle t1 Setup time 4 ns t2 Hold time 2 ns tod Output delay 7 20 9 Unit ns 13 ns Table 7. RMII Timing Parameters - KSZ8021/31RNL (25MHz input to XI pin, 50MHz output from REF_CLK pin) Timing Parameter Description tcyc Clock cycle t1 Setup time Min. Typ. Max. 20 ns 4 t2 Hold time 8 tod Output delay 9 Unit ns ns 13 15 ns Table 8. RMII Timing Parameters - KSZ8021/31RNL (50MHz input to XI pin) August 2010 35 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Auto-Negotiation Timing Figure 10. Auto-Negotiation Fast Link Pulse (FLP) Timing Timing Parameter Description Min. Typ. Max. 8 16 24 Units tBTB FLP Burst to FLP Burst tFLPW FLP Burst width ms tPW Clock/Data Pulse width tCTD Clock Pulse to Data Pulse 55.5 64 69.5 s tCTC Clock Pulse to Clock Pulse 111 128 139 s Number of Clock/Data Pulse per FLP Burst 17 2 ms 100 ns 33 Table 9. Auto-Negotiation Fast Link Pulse (FLP) Timing Parameters August 2010 36 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL MDC/MDIO Timing Figure 11. MDC/MDIO Timing Timing Parameter Description Min. Typ. tP MDC period t1MD1 MDIO (PHY input) setup to rising edge of MDC 10 ns tMD2 MDIO (PHY input) hold from rising edge of MDC 4 ns tMD3 MDIO (PHY output) delay from rising edge of MDC * [can vary with MDC clock frequency] 400 * Max. Unit ns ns Table 10. MDC/MDIO Timing Parameters August 2010 37 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Reset Timing The KSZ8021/31RNL reset timing requirement is summarized in Figure 12 and Table 11. Figure 12. Reset Timing Parameter Description Min. Max. Units tvr Supply voltage (VDDIO, VDDA_3.3) rise time 300 s tsr Stable supply voltage (VDDIO, VDDA_3.3) to reset high 10 ms tcs Configuration setup time 5 ns tch Configuration hold time 5 ns trc Reset to strap-in pin output 6 ns Table 11. Reset Timing Parameters The supply voltage (VDDIO, and VDDA_3.3) power-up waveform should be monotonic, and the 300s minimum rise time is from 10% to 90%. After the de-assertion of reset, it is recommended to wait a minimum of 100s before starting programming on the MIIM (MDC/MDIO) Interface. August 2010 38 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Reset Circuit The following reset circuit is recommended for powering up the KSZ8021/31RNL if reset is triggered by the power supply. Figure 13. Recommended Reset Circuit The following reset circuit is recommended for applications where reset is driven by another device (e.g., CPU or FPGA). At power-on-reset, R, C and D1 provide the necessary ramp rise time to reset the KSZ8021/31RNL device. The RST_OUT_n from CPU/FPGA provides the warm reset after power up. Figure 14. Recommended Reset Circuit for interfacing with CPU/FPGA Reset Output August 2010 39 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Reference Circuit for LED Strapping Pin The pull-up, float and pull-down reference circuits for the LED0/ANEN_SPEED strapping pin are shown in Figure 15 for 3.3V and 2.5V VDDIO. Figure 15. Reference Circuits for LED Strapping Pin For 1.8V VDDIO, LED indication support is not recommended due to the low voltage. Without the LED indicator, the ANEN_SPEED strapping pin is functional with 4.7K pull-up to 1.8V VDDIO or float for a value of `1', and with 1.0K pulldown to ground for a value of `0'. August 2010 40 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Magnetics Specification A 1:1 isolation transformer is required at the line interface. An isolation transformer with integrated common-mode chokes is recommended for exceeding FCC requirements. Tables 12 and 13 list recommended magnetic characteristics and qualified magnetics for the KSZ8021/31RNL. Parameter Value Turns ratio 1 CT : 1 CT Test Condition Open-circuit inductance (min.) 350H 100mV, 100kHz, 8mA Insertion loss (max.) -1.0dB 100kHz - 100MHz HIPOT (min.) 1500Vrms Table 12. Magnetics Selection Criteria Magnetic Manufacturer Part Number Auto MDI-X Number of Port Bel Fuse S558-5999-U7 Yes 1 Bel Fuse (Mag Jack) SI-46001-F Yes 1 Bel Fuse (Mag Jack) SI-50170-F Yes 1 Delta LF8505 Yes 1 LANKom LF-H41S-1 Yes 1 Pulse H1102 Yes 1 Pulse (low cost) H1260 Yes 1 Transpower HB726 Yes 1 TDK (Mag Jack) TLA-6T718A Yes 1 Table 13. Qualified Single Port 10/100 Magnetics Reference Clock - Connection and Selection A crystal or external clock source, such as an oscillator, is used to provide the reference clock for the KSZ8021/31RNL. For the KSZ8021/31RNL in RMII - 25MHz Clock Mode, the reference clock is 25MHz. The reference clock connections to XI (Pin 8) and XO (Pin 7), and the reference clock selection criteria are provided in Figure 16 and Table 14. Figure 16. 25MHz Crystal / Oscillator Reference Clock Connection August 2010 41 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Characteristics Value Units Frequency 25 MHz Frequency tolerance (max) 50 ppm Table 14. 25MHz Crystal / Reference Clock Selection Criteria For the KSZ8021/31RNL in RMII - 50MHz Clock Mode, the reference clock is 50MHz. The reference clock connection to XI (Pin 8), and the reference clock selection criteria are provided in Figure 17 and Table 15. Figure 17. 50MHz Oscillator Reference Clock Connection Characteristics Value Units Frequency 50 MHz Frequency tolerance (max) 50 ppm Table 15. 50MHz Oscillator / Reference Clock Selection Criteria August 2010 42 M9999-082710-1.0 Micrel, Inc. KSZ8021RNL / KSZ8031RNL Package Information 24-Pin (4mm x 4mm) QFN MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry, specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual property rights is granted by this document. Except as provided in Micrel's terms and conditions of sale for such products, Micrel assumes no liability whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser's use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser's own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. (c) 2010 Micrel, Incorporated. August 2010 43 M9999-082710-1.0