19-1854; Rev 5; 9/07 +3.3V, 2.7Gbps Dual 2 2 Crosspoint Switch The MAX3840 is a dual 2 2 asynchronous crosspoint switch for SDH/SONET DWDM and other high-speed data switching applications where serial data stream loop-through and protection channel switching are required. It is ideal for OC-48 systems with forward error correction. A high-bandwidth, fully differential signal path minimizes jitter accumulation, crosstalk, and signal skew. Each 2 2 crosspoint switch can fan out and/or multiplex up to 2.7Gbps data and 2.7GHz clock signals. All inputs and outputs are current mode logic (CML) compatible and easily adaptable to interface with an AC-coupled LVPECL signal. When not used, each CML output stage can be powered down with an enable control to conserve power. The typical power consumption is 460mW with all outputs enabled. The MAX3840 is compatible with the MAX3876 2.5Gbps clock and data recovery (CDR) circuit. The MAX3840 is available in a 32-pin exposed-pad QFN package (5mm 5mm footprint) and operates from a +3.3V supply over a temperature range of -40C to +85C. ________________________Applications SDH/SONET and DWDM Transport Systems Features Single +3.3V Supply 460mW Power Consumption 2psRMS Random Jitter 7psP-P Deterministic Jitter Power-Down Feature for Deselected Outputs CML Inputs/Outputs 6ps Channel-to-Channel Skew 100ps Output Edge Speed 5mm 5mm 32 QFN or Thin QFN Package Ordering Information PART TEMP RANGE PINPACKAGE PKG CODE MAX3840ETJ+ -40C to +85C 32 TQFN T3255-3 MAX3840EGJ -40C to +85C 32 QFN G3255-1 +Denotes a lead-free package. Add-Drop Multiplexers ATM Switch Cores WDM Cross-Connects Pin Configurations appear at end of data sheet. High-Speed Backplanes Typical Application Circuit VCC = +3.3V MAX3866 TIA AND LA MAX3876 CDR MAX3869 LASER DRIVER DATA CLOCK MAX3866 TIA AND LA MAX3876 CDR DATA MAX3840 CROSSPOINT SWITCH MAX3869 LASER DRIVER CLOCK ZO = 50 TRANSMISSION LINE ________________________________________________________________ Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. MAX3840 General Description MAX3840 +3.3V, 2.7Gbps Dual 2 2 Crosspoint Switch ABSOLUTE MAXIMUM RATINGS Supply Voltage, VCC .............................................-0.5V to +5.0V Input Voltage (CML) .........................(VCC - 1.0) to (VCC + 0.5V) TTL Control Input Voltage...........................-0.5V to (VCC + 0.5V) Output Currents (CML) .......................................................22mA Continuous Power Dissipation (TA = +85C) 32-Pin TQFN (derate 21.3mW/C above +85C) .................................1.38W 32-Pin QFN (derate 21.3mW/C above +85C) .................................1.38W Operating Temperature Range ...........................-40C to +85C Operating Junction Temperature Range ...........-55C to +150C Storage Temperature Range .............................-65C to +160C Lead Temperature (soldering, 10s) .................................+300C Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. DC ELECTRICAL CHARACTERISTICS (VCC = +3.0V to +3.6V, TA = -40C to +85C. Typical values are at VCC = +3.3V, TA = +25C, unless otherwise noted.) PARAMETER Supply Current SYMBOL ICC CONDITIONS MIN TYP MAX UNITS 140 190 mA 640 800 1000 mVP-P 85 100 115 All outputs enabled CML INPUT AND OUTPUT SPECIFICATIONS CML Differential Output Swing RL = 50 to VCC (Figure 2) Differential Output Impedance CML Output Common-Mode Voltage CML Single-Ended Input Voltage Range RL = 50 to VCC VIS CML Differential Input Voltage Swing CML Single-Ended Input Impedance VCC - 0.2 V VCC - 0.8 VCC + 0.5 V 300 2000 mVP-P 57.5 42.5 50 TTL SPECIFICATIONS 2.0 TTL Input High Voltage VIH TTL Input Low Voltage VIL TTL Input High Current IIH -10 +10 A TTL Input Low Current IIL -10 +10 A 2 V 0.8 _______________________________________________________________________________________ V +3.3V, 2.7Gbps Dual 2 2 Crosspoint Switch (VCC = +3.0V to +3.6V, TA = -40C to +85C. Typical values are at VCC = +3.3V, TA = +25C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS CML Input and Output Data Rate 2.7 Gbps CML Input and Output Clock Rate 2.7 GHz CML Output Rise and Fall Time tr, tf 20% to 80% CML Output Random Jitter RJ (Note 2) 2 DJ CML Output Deterministic Jitter 100 136 ps psRMS (Note 3) 7 20 psP-P CML Output Differential Skew tskew1 Any differential pair 7 25 ps CML Output Channel-toChannel Skew tskew2 Any two outputs 15 40 ps Propagation Delay from Inputto-Output 185 td ps CML Differential Output Swing for 2.7Gbps Input Data RL = 50 to VCC (Note 4) 600 mVP-P CML Differential Output Swing for 2.7GHz Input Clock RL = 50 to VCC (Note 5) 520 mVP-P Note 1: Note 2: Note 3: Note 4: Note 5: AC characteristics are guaranteed by design and characterization. Measured with 100mVP-P noise (f 2MHz) on the power supply. Deterministic jitter (DJ) is the arithmetic sum of pattern-dependent jitter and pulse-width distortion. Measured with 300mVP-P differential 1010... data pattern driving the inputs. Measured with 300mVP-P differential clock at 2.7GHz driving the inputs. _______________________________________________________________________________________ 3 MAX3840 AC ELECTRICAL CHARACTERISTICS 2 Crosspoint Switch Typical Operating Characteristics (VCC = +3.3V, TA = +25C, unless otherwise noted.) SUPPLY CURRENT vs. TEMPERATURE SUPPLY CURRENT (mA) 2 OUTPUTS ENABLED 100 1 OUTPUT ENABLED 80 0 OUTPUTS ENABLED 60 40 20 MAX3840 toc02 3 OUTPUTS ENABLED 800 CML DIFFERENTIAL VOLTAGE (mVP-P) 4 OUTPUTS ENABLED 140 120 CML DIFFERENTIAL VOLTAGE MAX3840 toc01 160 750 700 650 600 550 500 450 400 350 300 250 200 0 -50 -30 -10 10 50 30 TEMPERATURE (C) 70 90 -50 -10 10 50 30 TEMPERATURE (C) 70 90 MAX3840 toc04 20 MAX3840 toc03 INPUT = 223 - 1PRBS -30 CHANNEL-TO-CHANNEL SKEW vs. TEMPERATURE 2.7Gbps EYE DIAGRAM 18 16 14 TMIE (ps) 150mV/div MAX3840 +3.3V, 2.7Gbps Dual 2 12 10 8 CHANNEL B 6 4 2 CHANNEL A 0 54ps/div -50 -30 -10 10 30 50 70 TEMPERATURE (C) 4 _______________________________________________________________________________________ 90 +3.3V, 2.7Gbps Dual 2 2 Crosspoint Switch PIN NAME FUNCTION 1 ENB1 Channel B1 Output Enable, TTL Input. A TTL low input powers down B1 output stage. 2 DIB1+ Channel B1 Positive Signal Input, CML 3 DIB1- Channel B1 Negative Signal Input, CML 4 ENB0 Channel B0 Output Enable, TTL Input. A TTL low input powers down B0 output stage. 5 SELB0 Channel B0 Output Select, TTL Input. See Table 1. 6 DIB0+ Channel B0 Positive Signal Input, CML 7 DIB0- Channel B0 Negative Signal Input, CML 8 SELB1 Channel B1 Output Select, TTL Input. See Table 1. 9, 24 GND Supply Ground 10, 13, 16, 17, 20, 23 VCC Positive Supply 11 DOB0- Channel B0 Negative Output, CML 12 DOB0+ Channel B0 Positive Output, CML 14 DOB1- Channel B1 Negative Output, CML 15 DOB1+ Channel B1 Positive Output, CML 18 DOA1- Channel A1 Negative Output, CML 19 DOA1+ Channel A1 Positive Output, CML 21 DOA0- Channel A0 Negative Output, CML 22 DOA0+ Channel A0 Positive Output, CML 25 SELA1 Channel A1 Output Select, TTL Input. See Table 1. 26 DIA0+ Channel A0 Positive Signal Input, CML 27 DIA0- Channel A0 Negative Signal Input, CML 28 SELA0 Channel A0 Output Select, TTL Input. See Table 1. 29 ENA0 Channel A0 Output Enable, TTL Input. A TTL low input powers down A0 output stage. 30 DIA1+ Channel A1 Positive Signal Input, CML 31 DIA1- Channel A1 Negative Signal Input, CML 32 ENA1 Channel A1 Output Enable, TTL Input. A TTL low input powers down A1 output stage. EP Exposed Pad Ground. The exposed pad must be soldered to the circuit board ground for proper electrical and thermal operation. _______________________________________________________________________________________ 5 MAX3840 Pin Description MAX3840 +3.3V, 2.7Gbps Dual 2 2 Crosspoint Switch Table 1. Output Routing ROUTING CONTROLS OUTPUT CONTROLS SELA0/SELB0 SELA1/SELB1 Signal at DOA0/DOB0 Signal at DOA1/DOB1 0 0 1 1 DIA0/DIB0 DIA0/DIB0 0 1 1 1 DIA0/DIB0 DIA1/DIB1 1 0 1 1 DIA1/DIB1 DIA0/DIB0 1 1 1 1 DIA1/DIB1 DIA1/DIB1 X X 0 0 Power Down Power Down DIA0+ DIA0- CML ENA0/ENA1 ENB0/ENB1 OUTPUT SIGNALS DOA0+ 0 CML+ CML 1 DOA0ENA0 SELA0 320mV MIN DOA1+ 0 CML DIA1+ DIA1- 500mV MAX CML 1 DOA1ENA1 CML- SELA1 DIB0+ DIB0- CML DOB0+ 0 CML 1 DOB0640mV MIN ENB0 SELB0 DOB1+ 0 DIB1+ DIB1- 1000mV MAX CML CML 1 (CML+) - (CML-) DOB1ENB1 SELB1 Figure 1. Functional Block Diagram _______________ Detailed Description The block diagram in Figure 1 shows the MAX3840 architecture. The SELA_ and SELB_ pins control the routing of the signals through the crosspoint switch. Each output of the crosspoint switch drives a CML output driver. Each of the outputs, DOA_ and DOB_, is enabled or disabled by the respective ENA_ and ENB_ pins. 6 Figure 2. CML Output Levels CML Inputs and Outputs CML is used to simplify high-speed interfacing. Onchip input and output terminations minimize the number of external components required while improving signal integrity. The CML output signal swing is small, resulting in lower power consumption. The internal 50 input and output terminations minimize reflections and eliminate the need for external terminations. _______________________________________________________________________________________ +3.3V, 2.7Gbps Dual 2 Interfacing PECL Inputs and Outputs to the MAX3840 For information on interfacing with CML, refer to Maxim Application Note HFAN-01.0, Introduction to LVDS, PECL, and CML. 2 Crosspoint Switch Layout Techniques For best performance, use good high-frequency layout techniques, filter VCC supplies, and keep ground connections short. Use multiple vias where possible. Also, use controlled-impedance transmission lines to interface with the MAX3840 data inputs and outputs. ___________________ Interface Models Figure 3 shows the interface model for the CML inputs, and Figure 4 shows the model for CML outputs. VCC MAX3840 VCC VCC 50 50 50 DIA0+ DOA0- DOA0+ VCC 50 DIA0- MAX3840 Figure 3. CML Input Model Figure 4. CML Output Model _______________________________________________________________________________________ 7 MAX3840 Applications Information 2 Crosspoint Switch VCC SELA1 25 DOA1- DIA0+ 26 DOA1+ DIA0- 27 VCC SELA0 28 DOA0- ENA0 29 DOA0+ DIA1+ 30 VCC DIA1- 31 TOP VIEW GND ENA1 TOP VIEW 32 Pin Configurations 24 23 22 21 20 19 18 17 ENB1 1 24 GND SELA1 25 16 VCC DIB1+ 2 23 VCC DIA0+ 26 15 DOB1+ DIB1- 3 22 DOA0+ DIA0- 27 14 DOB1- ENB0 4 21 DOA0- SELA0 28 13 VCC SELB0 5 20 VCC ENA0 29 12 DOB0+ DIB0+ 6 19 DOA1+ DIA1+ 30 11 DOB0- DIB0- 7 18 DOA1- DIA1- 31 10 VCC SELB1 8 17 VCC ENA1 32 9 GND MAX3840 6 7 8 DIB0- SELB1 THIN QFN NOTE: THE EXPOSED PAD MUST BE SOLDERED TO THE SUPPLY GROUND. Package Information Chip Information TRANSISTOR COUNT: 1200 PROCESS: Bipolar (SiGe) 5 DIB0+ DIB1- QFN NOTE: THE EXPOSED PAD MUST BE SOLDERED TO THE SUPPLY GROUND. 4 SELB0 3 ENB0 2 DIB1+ 16 VCC 1 ENB1 15 13 VCC 14 12 DOB0+ DOB1- 11 DOB1+ 10 VCC DOB0- 9 + MAX3840 GND MAX3840 +3.3V, 2.7Gbps Dual 2 For the latest package outline information, go to www.maxim-ic.com/packages. PACKAGE TYPE DOCUMENT NO. 32 QFN 21-0091 32 TQFN 21-0140 Revision History Rev 1; 11/01: Rev 2; 5/03: Rev 3; 5/05: Rev 4; 12/05: Corrected specification. Added package code (page 1); updated package drawing (page 10). Added lead-free package (pages 1, 2, 8, 11, 12). Changed input voltage swing from 1.5VP-P (max) to 2.0VP-P (max). Rev 5; 9/07: Added two AC amplitude specifications to increase test coverage for 2.5Gbps and 2.7GHz clock inputs (page 3); removed package drawings and added package table (page 8). Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 (c) 2007 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.