19-0349; Rev 1; 3/95 MAX194 Evaluation System/Evaluation Kit The MAX194 Evaluation System (MAX194EVC16-DIP) includes the MAX194 evaluation kit and Maxim's 68HC16 module. Evaluation software supplied with the kit demonstrates the use of the MAX194 (or the MAX195) with Motorola's high-speed QSPI serial interface. Complete source code is included. The EV system requires an IBM PC with a serial port and a 5 1/4" disk drive. The stand-alone MAX194 Evaluation Kit (MAX194 EVKIT-DIP) is an assembled and tested PC board that embodies the standard application circuit. Separate power, digital, and analog ground planes minimize noise. Jumpers allow several operating modes. The board generates its own interface timing signals, or can be connected to a user-provided serial interface. ____________________________Features Proven PC Board Layout Complete Source Code Provided Shutdown-Mode Evaluation High-Speed Serial Interface Convenient Test Points Provided On-Board Operates from a Single 9V to 15V DC Power Supply Evaluates Both the 14-Bit MAX194 and the 16-Bit MAX195 ______________Ordering Information PART MAX194EVC16-DIP MAX194EVKIT-DIP 68HC16MODULE TEMP. RANGE 0C to +70C 0C to +70C 0C to +70C BOARD TYPE Through-Hole Through-Hole Through-Hole 68HC16 MODULE { { ___________________________________________________________________EV System MAX194/MAX195 EV BOARD Note: PC board labeled MAX195 for both MAX194 EV kit and MAX195 EV kit. ________________________________________________________________ Maxim Integrated Products 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. 1 Evaluates: MAX194/MAX195 _______________General Description Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit ________EV System Component List QUANTITY DESCRIPTION 1 MAX194 Evaluation Kit (MAX194EVKIT-DIP) 1 68HC16 C Module (68HC16MODULE) ___MAX194 EV System Quick Start This section applies only to the use of the MAX194 EV kit with the 68HC16 module. 1) Copy the files from the distribution disk to your hard disk. Store the MAX194 EV kit software in its own directory. 2) Carefully align the 40-pin header of the MAX194 EV kit with the 40-pin connector of the C module. Gently press them together. The two boards should be flush against each other. Note: The MAX194 EV kit is not supported by the 80C32 module. 3) Make sure the jumpers are configured in accordance with Table 1. 4) Connect a 9V to 15V DC power source to the C module, using a small screwdriver. The terminal block is located next to the on/off switch, in the upper right corner of the C module. Plus and minus are marked on the board. available serial port uses a 25-pin connector, use a standard 25-pin to 9-pin adapter. 6) To start up the MAX194 software on the IBM PC, set the current directory to match the directory where the Maxim software is stored, and then type the program name "MAX194". 7) The program will ask which serial port is connected to the C module. Press the space bar until the correct port is highlighted, then press ENTER. The MAX194 program will switch to terminal-emulation mode. 8) At this point, apply power to the 68HC16 module. The LED should light, and within 5 seconds the program will display a logon banner. Note that the LED is a status indicator, not a power light. It flashes to indicate module readiness. 9) To download and run the RAM resident code on the C module, press ALT+L (that is, hold down the ALT key as you strike the L key). The program prompts for the file name. Press the ENTER key to download and run the file KIT194.S19 on the 68HC16 module. The KIT194.S19 RAM resident program offers a menu of commands listed in Table 2. To evaluate the MAX195, replace U1 with the MAX195. 5) Connect a cable from the computer's serial port to the C module. If using a 9-pin serial port, use a straight-through 9-pin female-to-male cable. If the Table 1. Jumper Configuration when Used with 68HC16 Module JUMPER STATE JU1 Closed JU3 JU4 JU5 JU6 JU7 2 FUNCTION Table 2. List of Commands Available in KIT194.S19 COMMAND FUNCTION Ground the SCLK pin ? List available commands. QSPI Conversion clock comes from QSPI clock R Read the MAX194. QSPI Chip-select is driven by QSPI PCS0 -- Perform continuous conversions. QSPI Conversion start is driven by QSPI PCS0 Open = Normal Operation. Closed = Reset; do not close this jumper when using the C module, because the C drives the reset pin. 68HC16 module selects bipolar/ unipolar/shutdown modes O Oscilloscope demonstration--observe system timing relationships by operating the MAX194 at full speed without processing data. Open AUTO ! Reset the MAX194. B Select bipolar mode. U Select unipolar mode. H Select hexadecimal output. D Select decimal output. L Toggle low-power mode on/off. T Set power-up delay and sleep time. S Collect a fixed number of samples. _______________________________________________________________________________________ MAX194 Evaluation System/Evaluation Kit DESCRIPTION Stand-Alone MAX194 _________________EV Kit Quick Start This section applies only to the use of the MAX194 EV kit by itself, without the C module. DESIGNATION QTY C1, C2, C4, C5, C19, C20, C23-C26, C29 11 0.1F ceramic capacitors C3 1 1F ceramic capacitor C6, C7 2 15F, 20V low-ESR capacitors Sanyo OS-CON 20SA14 C8-C11, C13-C16, C21 9 10F, 25V tantalum capacitors C12, C18, C27 3 100F, 25V electrolytic capacitors C17, C171 2 0.01F ceramic capacitors C22 1 47F low-ESR capacitor Sanyo OS-CON 6SA47M D1, D2 2 1N5819 Schottky diodes J1 1 2x20 female data connector J2 1 10-pin header JU1, JU6 2 2-pin headers JU3, JU7 2 3-way headers JU4, JU5 2 3-pin headers R1, R2 2 10, 5% resistors R3, R8 2 680, 5% resistors R4, R41 2 22, 5% resistors Table 3. Jumper Configuration for StandAlone MAX194 EV Kit 1) Make sure the jumpers are configured in accordance with Table 3. 2) Connect the oscilloscope's channel A probe to the EOC test point on header J2, and the channel B probe to the DOUT test point. Ground the scope probes to the DGND test point or to the GND power pad. Trigger on the positive edge of channel A. Set the time base to 2s per division, and set the vertical gain to 2V per division. 3) Apply +12V DC to the terminals labeled +12V and GROUND. The board draws less than 30mA of supply current. 4) Momentarily close JU6 to reset the MAX194 EV kit. Leave JU6 open for normal operation. 5) Apply a 0V to 4V signal source between the terminals labeled INPUT+ and INPUT-. The conversion codes may be observed on the oscilloscope's channel A. See the appropriate data sheet for timing information. R5, R51 2 47k, 5% resistors JUMPER STATE R6, R10, R11, R13, R61 5 1k, 5% resistors JU1 Closed R7 1 10k, 5% resistor R9 1 10M, 5% resistor JU3 OSC Conversion clock comes from crystal oscillator module U1 1 Maxim MAX194 JU4 GND U2 1 Maxim MAX874 Tie CS to GND, enabling data output on DOUT U3 1 79L05 negative linear regulator JU5 CONT Tie CONV to EOC, continuous-conversion mode U4 1 Optional crystal oscillator JU6 Open U5, U8 2 Maxim MAX400 Open = Normal Operation Closed = Reset UNI 1 78L05 positive linear regulator JU7 U6 U7 1 ICL7662 inverter FUNCTION Ground the SCLK pin Select unipolar mode _______________________________________________________________________________________ 3 Evaluates: MAX194/MAX195 Stand-Alone EV Kit ____________________Component List Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit __Detailed Description of Software EPROM Resident Program A small bootstrap program is stored in the EPROM located on the 68HC16 board. The EPROM resident program initializes the 68HC16, tests the static RAM, configures the chip-select logic, establishes serial communications with the host, and downloads program KIT194 into RAM. It starts operating on power-up or whenever the RESET button is pressed. After RESET, it tests the RAM, then waits to receive a serial character on its serial port before transmitting its identification banner. RAM Resident Program KIT194.S19 is a 68HC16 RAM-resident program that is transferred from disk to the static RAM on the 68HC16 module. When the KIT194 program is running, it offers the commands listed in Table 2. Personal Computer Program MAX194.EXE, which runs on an IBM-compatible computer, is a terminal program that establishes communication with the 68HC16 module and allows the user to download and run the Maxim-provided RAM resident program. The serial communication baud rate is initiated at 1200 baud (default setting) to ensure proper operation with basic systems. The MAX194.EXE program provides several commands that are associated with the host computer. These commands are listed in Table 4. The MAX194.EXE program can store the text of a terminal session in a log file. To begin recording the terminal session, press ALT+O [the letter O]. The program will ask for a file name. Press ENTER to accept the default file name, or type in a different name. If a file with that Table 4. Commands Available in MAX194.EXE Terminal Program KEY 4 COMMAND ALT+L Load and run resident code on 68HC16. ALT+X Exit to DOS. ALT+P Change port (COM1, COM2). ALT+R Send RESET command to 68HC16. ALT+O Open a log file. ALT+C Close the log file. ALT+B Display baud rate menu. ALT+1 1200 baud ALT+4 4800 baud ALT+9 9600 baud ALT+2 19200 baud name already exists, the old file will be erased. To close the file, press ALT+C. The log file will contain the complete text of the terminal session from the time the file is opened until it is closed. Using the QSPI to Read the MAX194 The 68HC16 module uses its Queued Serial Peripheral Interface (QSPI) in master mode to read the MAX194. The MAX194 EV kit software uses the algorithm described below. Refer to the example program of Listing 1, which assigns QSPI entries 0 and 1 and programmable chip-select PCS0 to the MAX194. Note: This interface scheme requires that the QSPI clock be active during the MAX194 reset (see Reset and Calibration Procedure section). 1) Initialize the QSPI parameters as follows: PARAMETER VALUE SPBR 5 1.68MHz serial clock EXPLANATION CPOL 0 Serial clock is low when idle CPHA 1 CPOL CPHA, data valid on falling clock edge BITS $0A DSCKL 2 Delay 119ns between CS and first clock in the first QSPI transfer to satisfy MAX194 tDA. COMD.0 $D0 Control RAM for first QSPI transfer: CONT = 1, BITSE = 1, DTL = 0, DSCK = 1, PSC0 = 0 COMD.1 $40 Control RAM for second QSPI transfer: CONT = 0, BITSE = 1, DTL = 0, DSCK = 0, PSC0 = 0 NEWQP 0 Index of first queue entry to execute ENDQP 1 Index of last valid queue entry Ten bits per QSPI transfer. Use two consecutive QSPI transfers to read the MAX194. 2) Verify that EOC is low before starting the conversion. 3) Start the QSPI transfer. 4) Wait until QSPI transfer is complete. The CPU may perform other tasks while waiting. 5) Extract the significant bits from QSPI RAM. Bits B13-B06 are located in QSPI receive RAM entry RR0 bits 7-0, and bits B05-B00 are located in entry RR1 bits 9-4. RR1 bits 3-2 are the sub-LSB bits of the MAX194 (see Table 5). _______________________________________________________________________________________ MAX194 Evaluation System/Evaluation Kit _______________________________________________________________________________________ Evaluates: MAX194/MAX195 Listing 1. Sample Code for 68HC16 Interface 5 Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit Using Bit-Pushing to Read the MAX194 _Detailed Description of Hardware The MAX194 may be interfaced using a bit-pushing algorithm, such as the following: Jumper Options 1) Verify that EOC is low before starting the conversion. 2) Assert CONV low to begin conversion. 3) Wait until EOC becomes high. Conversion has begun. Several jumper blocks allow different configurations of the MAX194. Jumper functions are listed in Table 6. See the Voltage Reference and Measuring Supply Current sections. 4) Set CONV high. 5) Wait until EOC becomes low. Conversion is complete. 6) Assert SCLK low. Table 6. Jumper Settings JUMPER POSITION Closed JU1 7) Assert CS low. Open 8) Clear the 16-bit result register. 9) Repeat 16 times: 9-1. Set SCLK high. 9-2. Rotate the 16-bit result register left. 9-3. Read DOUT into least significant bit of the result register. 9-4. Assert SCLK low. 10) Set CS high. "OSC" JU3 "EXT" "QSPI" "QSPI" JU4 Reset and Calibration Procedure When the MAX194 is installed in an environment with an unregulated temperature, thermal variation can cause DC offset errors. Transients on the power supply or reference during the power-on calibration are also a source of DC offset error. These errors can be eliminated by performing re-calibration, as outlined below: 1) Assert the MAX194 RESET pin low. "QSPI" Connects CONV to QSPI chip-select PCS0. "CONT" Connects CONV to EOC for continuous conversion mode. Closed "SHDN" JU7 Allows the SCLK pin to be driven by the user. Conversion clock is driven by crystal oscillator U4. Conversion clock is driven by the EXTCLK input pad. Conversion clock is driven by the QSPI serial clock. Connects CS to QSPI chip-select PCS0. Connects CS to ground; data output is always enabled. Open JU6 Ground the SCLK pin. "GND" JU5 2) Run the conversion clock until EOC becomes high. 3) Set the MAX194 RESET pin high. 4) Run the conversion clock until EOC becomes low. For best accuracy, a typical application circuit should allow time for the power supply and ambient temperature to settle before re-calibrating the MAX194. Refer to the Calibration section of the MAX194 data sheet. FUNCTION Normal operating mode. Momentary closure resets and re-calibrates the MAX194. Do not close this jumper if the C module is connected. Select shutdown mode. "AUTO" Lets 68HC16 drive the BP/UP/SHDN pin. If no C is connected, bipolar input mode is selected. "UNI" Select unipolar mode. Open Select bipolar mode. Data Connector Interface The 68HC16 module and MAX194 communicate through the QSPI port on the 40-pin data connector. Table 7 lists the function of each pin. Table 5. QSPI Receive Format for MAX194 ADDR 15 14 13 12 11 10 RR0 x x x x x x RR1 x x x x x x 6 9 8 7 6 5 4 x x B13 B12 B11 B10 B5 B4 B3 B2 B1 B0 3 2 1 0 B9 B8 B7 B6 sub sub x x _______________________________________________________________________________________ MAX194 Evaluation System/Evaluation Kit Voltage Reference The voltage reference U2 provides a 4.096V reference, which is buffered by U5. The buffer isolates the reference from the MAX194's capacitive switching load. To eliminate the buffer circuit, cut traces JU8 and JU9 and connect a wire from JU9 pin 1 to the VREF pad. Reference Buffer The reference input to the MAX194 may be buffered by U5. The MAX400 op amp is used because of its low V OS drift. By using a bipolar (instead of CMOS) op amp, the substrate can be connected to the quiet analog ground, reducing the noise coupled through the power supplies. The feedback circuit consists of four passive components: R4, R6, C17, and R5. R4 isolates the op-amp's output from the heavy capacitive load that bypasses the VREF pin. R6 makes the network accurate at the reference input (without R6, the reference voltage would appear at the output of the op amp). C17 compensates the high-frequency response by making R5 dominate at high frequencies. The reference buffer U5 draws its power through the lowpass filter formed by R3 and C18. The filter provides the necessary power-supply rejection. U5 is powered by the unregulated input supply to ensure enough headroom to buffer the 4.096V reference. Layout, Power Supplies, and Grounding Good PC board layout necessary to achieve specified performance, and an analog ground plane is essential for optimum performance. The PC board layout artist must be provided with explicit instructions, preferably a pencil sketch of the placement of sensitive analog components and the routing of ground connections. See the EV kit PC board layout for an example. Use the following guidelines: 1) At the schematic level, keep the analog power supplies and grounds separate from all other power supplies and grounds. Digital power may be connected to analog power through a 10 series resistor to attenuate digital noise. 2) Cluster the MAX194, the voltage reference, and any input or reference buffers near the site where the analog signal enters the board. Place 0.1F ceramic decoupling capacitors within 10mm of the MAX194's power-supply and voltage-reference pins. 3) Keep the analog-input signal ground return separate from the analog ground plane, connecting to analog ground only at the AGND pin of the MAX194. The analog input and its signal groundreturn traces should both follow the same route to help reject common-mode noise. Table 7. Data-Interface Connections PIN NO. 1-4 5, 6 7, 8 9-26 27 28, 29, 30 31 32 33, 34 35 36 37 38 39, 40 68HC16 SIGNAL GND +12V +5V Reserved IC1 Reserved OC2 OC3 Reserved MISO Reserved SCK PCS0 Reserved MAX194 SIGNAL GND +12V VDDD Reserved EOC Reserved RESET BP/UP/SHDN Reserved DOUT Reserved CLK CS Reserved FUNCTION Ground Unregulated 12V DC Supply Regulated +5V DC from 68HC16 Module Reserved End-of-Conversion Output from MAX194 Reserved Active-Low RESET to MAX194 Shutdown/Bipolar/Unipolar Input to MAX194 Reserved QSPI Master Input; Serial Data Output from MAX194 Reserved QSPI Serial Clock from 68HC16 QSPI Chip-Select from 68HC16 Reserved _______________________________________________________________________________________ 7 Evaluates: MAX194/MAX195 Analog Input Buffer The analog input to the MAX194 may be buffered by U8. A MAX400 is used because of its low VOS drift. The feedback circuit consists of four passive components: R41, R61, C171, and R51. R41 isolates the op-amp's output from the dynamic capacitive load at the AIN input. R61 makes the network accurate at the reference input (without R61, the reference voltage would appear at the output of the op amp). C171 compensates the high-frequency response by making R51 dominate at high frequencies. Input offset may be improved by adding a 1000pF to 0.01F ceramic capacitor at site C28. Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit The MAX194 evaluation board generates its own highquality power supplies from a single DC input (8V to 20V), such as a plug-in wall transformer. When the MAX194 evaluation board is connected to the 68HC16 C module, the C module uses the unregulated input supply to generate its own separate +5V digital supply. U6 converts the unfiltered input down to +5V to provide the VDDA analog supply. Current spikes from the digital supply VDDD are attenuated by R1. Schottky diode D1 protects the device substrate. U7 inverts the +12V to -12V, and U3 regulates the -12V to -5V, providing the VSSA analog supply. Measuring Supply Current To measure the supply current drawn by the MAX194, turn off the power and prepare the board by carefully cutting the traces at IS1, IS2, IS3, and IS4, and installing 2-pin headers and shunts (see Table 8). 8 Table 8. Current-Sense Jumpers JUMPER POWER SUPPLY DESCRIPTION IS1 VDDA Analog +5V IS2 VSSA Analog -5V IS3 VSSD Digital -5V IS4 VDDD Digital +5V Each supply may be measured by replacing the corresponding shunt with a current-meter connection. For example, to measure the current drawn by the +5V digital supply, replace the shunt at IS4 with a current meter. The direction of current flow is marked with arrows on the silkscreen. Do not connect or disconnect the current meter while the power is on. After observing supply current in operating and shutdown modes, the board may be restored by installing shunts at IS1-IS4. _______________________________________________________________________________________ MAX194 Evaluation System/Evaluation Kit = DIGITAL GROUND R51, 47k IS4 D2 1N5819 IS1 R12, 20k R61 1k 7 C7 15F 8 6 AIN R41 22 C29 0.1F 2 1 JU2 C6 15F = ANALOG GROUND +9V / FILTERED C171 0.01F VDDD 3 U8 5 MAX400CPA 4 R9 10M C26 0.1F C5 0.1F C1 0.1F 4 DIRECT INPUT VDDA C28 (OPTIONAL) 1000pF 13 to 0.01F MAX194 CONV CS DOUT SCLK EOC BP / UP/ SHDN 10 AIN RESET 9 CONV 8 CS 5 DOUT 3 SCLK 7 EOC 1 BP / UP/ SHDN 2 CLK C9 10F 11 1 12 4.096V C22 47F LOW-ESR SANYO 6SA47M C3 1F +9V / FILTERED R6 1k 7 1 JU8 6 VREF C2 0.1F 3 5 U5 MAX400CPA -9V / FILTERED 2 8 4 C8 10F IS2 VSSD 5 R5, 47k C17 0.01F R4 22 IS3 TRIM 6 REFERENCE BUFFER 15 C4 0.1F GND VOUT R17 R16 R15 4M (OPTIONAL) 1M (OPTIONAL) 2M (OPTIONAL) REF 14 MAX874 TEMP 4 8 7 VIN 3 C23 0.1F COMP U2 2 CONVCLK DGND VSSD AGND VSSA 6 C19 0.1F +12V / UNREGULATED C30 (OPTIONAL) 15F 20V U1 RESET -9V / FILTERED 16 VDDD BUFFERED INPUT 1 2 C24 0.1F JU9 C21 10F C20 0.1F 3 JU10 VSSA Figure 1. MAX194 EV Kit Schematic _______________________________________________________________________________________ 9 Evaluates: MAX194/MAX195 INPUT BUFFER (OPTIONAL) VDDA VDDD P1.0 / IC1 J1-27 P1.1 / IC2 J1-28 P1.2 / IC3 J1-29 P1.3 / OC1 J1-30 P1.4 / OC2 J1-31 P1.5 / OC3 J1-32 P1.6 / OC4 J1-33 P1.7 / IC4 J1-34 = DIGITAL GROUND RESET EOC JU6 = ANALOG GROUND R7, 10k R10, 1k "AUTO" 3 "SHDN" CS VDDD R11, 1k 2 JU7 2 4 "UNI" 1 1 QSPI_PCSO 3 "QSPI" JU4 "GND" Chip Select BP / UP/ SHDN 2x20 HEADER MISO J1-35 MOSI J1-36 SCK J1-37 PCSO / SS J1-38 CLKOUT J1-39 PWMA J1-40 DOUT CONV R13, 1k EOC "CONT" 1 QSPI_PCSO 2 "QSPI" 3 JU5 CONV Select QSPI_PCSO VDDD 14 11 8 U4 C25 0.1F "OSC" 2 3 "QSPI" "EXT" JU3 4 SCLK JU1 EXTCLK1 1 XTAL OSC. CONVCLK 7 VDDD J2-10 J2-9 J2-8 J2-7 J2-6 J2-5 J2-4 J2-3 J2-2 J2-1 TEST POINTS EOC J3-2 (FSR) DOUT R18 270 (OPTIONAL) J3-4 (DR) CONCLK VDDD CONVCLK BP / UP/ SHDN RESET EOC DOUT CONV CS SCLK (CLKR) J3-9 DGND Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit (XF1) J3-8 CONV J3-1 J3-10 Figure 1. MAX194 EV Kit Schematic (continued) 10 ______________________________________________________________________________________ R19 270 (OPTIONAL) MAX194 Evaluation System/Evaluation Kit GND J1-1 GND J1-2 GND J1-3 GND J1-4 = ANALOG GROUND = POWER GROUND R3 600 GND Evaluates: MAX194/MAX195 +12V / UNREG +9V / FILTERED C18 100F 2x20 HEADER UNREG +12VDC J1-5 UNREG +12VDC J1-6 C27 100F +12V / UNREG -9V / FILTERED R8 600 POS12 -12V / UNREG POS5 U6 3 +12V / UNREG IN OUT 1 VDDA 78LO5 C16 10F D1 1N5819 JU11 HC16 +5V 2x20 HEADER R1 10 C15 10F GND 2 VDDD J1-7 J1-8 X3 AGND PGND +12V / UNREG C10 10F U7 ICL7662 1 2 C11 10F 3 4 NC CAP+ V+ OSC GND LV CAP- VOUT 8 7 6 C12 100F 2 C14 10F GND U3 79LO5 5 -12V/UNREG VSSD 1 C13 10F IN NEG12 OUT 3 R2 10 VSSA NEG5 Figure 1. MAX194 EV Kit Schematic (continued) ______________________________________________________________________________________ 11 Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit Figure 2. MAX194 EV Kit Component Placement Guide--Component Side 12 ______________________________________________________________________________________ MAX194 Evaluation System/Evaluation Kit Evaluates: MAX194/MAX195 Figure 3. MAX194 EV Kit PC Board Layout--Component Side ______________________________________________________________________________________ 13 Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit Figure 4. MAX194 EV Kit PC Board Layout--Solder Side 14 ______________________________________________________________________________________ MAX194 Evaluation System/Evaluation Kit DESIGNATION C1, C2, C3 QTY 3 C4, C5 2 C6, C7 C8 C9 C10-C14 D1 J1 J2 2 1 0 5 1 1 1 J3 1 J4 JU1 JU2 JU3 JU4 JU5 L1 L2 LED1 R1 0 0 0 0 0 0 0 0 1 1 DESCRIPTION 1F ceramic capacitors 22F, 25V radial-lead electrolytic capacitors 22pF capacitors 0.01F capacitor Reference designator, not used 0.1F capacitors 1N4001 diode 40-pin right-angle male connector 2-circuit terminal block Right-angle printed circuit board mount, DB9 female socket Empty Empty Reference designator, not used Empty Empty Empty Empty Empty Light-emitting diode 10M, 5% resistor 68HC16 Module ________________General Description The 68HC16 module is an assembled and tested printed-circuit board intended for use with Maxim's highspeed serial-interface evaluation kits (EV kits). The module uses an inexpensive 8-bit implementation of Motorola's MC68HC16Z1 microcontroller (C) to collect data samples at high speed using the QSPITM interface. It requires an IBM-compatible personal computer and an external DC power supply, typically 12V DC or as specified in EV kit manual. Maxim's 68HC16 module is provided to allow customers to evaluate selected Maxim products. It is not intended to be used as a microprocessor development platform, and such use is not supported by Maxim. DESIGNATION C1, C2, C3 QTY 3 C4, C5 2 C6, C7 C8 C9 C10-C14 D1 J1 J2 2 1 0 5 1 1 1 J3 1 J4 JU1 JU2 JU3 JU4 JU5 L1 L2 LED1 R1 0 0 0 0 0 0 0 0 1 1 DESCRIPTION 1F ceramic capacitors 22F, 25V radial-lead electrolytic capacitors 22pF capacitors 0.01F capacitor Reference designator, not used 0.1F capacitors 1N4001 diode 40-pin right-angle male connector 2-circuit terminal block Right-angle printed circuit board mount, DB9 female socket Empty Empty Reference designator, not used Empty Empty Empty Empty Empty Light-emitting diode 10M, 5% resistor 68HC16 Module ________________Detailed Description Power Input Connector J2 The 68HC16 module draws its power from a user-supplied power source connected to terminal block J2. Be sure to note the positive and negative markings on the board. A three-terminal 5V regulator allows input voltages between 8V and an absolute maximum of 20V. The 68HC16 module typically requires 200mA of input current. 68HC16 Microcontroller U1 is Motorola's 68HC16Z1 C. Contact Motorola for C information, development, and support. Maxim EV kits use the high-speed queued serial peripheral interface (QSPI) and the internal chip-select generation. A MAX707 on the module monitors the 5V logic supply, generates the power-on reset, and produces a reset pulse whenever the reset button is pressed. TM QSPI is a trademark of Motorola Corp. ______________________________________________________________________________________ 15 Evaluates: MAX194/MAX195 _____________________________________________68HC16 Module Component List Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit The 68HC16 uses a phase-locked loop (PLL) to set its bus speed. Crystal Y1 is a 32.768kHz frequency reference. The internal oscillator runs 256 times faster than the external crystal. When the 68HC16 is reset, it waits for the PLL to lock before it executes any software. After the PLL locks onto the reference frequency, the software doubles the clock speed by writing to the clock synthesizer control register, selecting a bus speed of 16.78MHz. U5, the user RAM area, is a 32kbyte CMOS static RAM. The 74HCT245 octal buffer lets the 68HC16 module access an 8-bit port on the 40-pin interface connector. This memory-mapped port consists of separate read and write strobes, four chip selects, four address LSBs, and eight data bits. Table 9. Serial Communications Port J3 PIN NAME FUNCTION 1 DCD Handshake; hard-wired to DTR and DSR 2 RXD RS-232-compatible data output from 68HC16 module 3 TXD RS-232-compatible data input to 68HC16 module 4 DTR Handshake; hard-wired to DCD and DSR 5 GND Signal ground connection 6 DSR Handshake; hard-wired to DCD and DTR 7 RTS Handshake; hard-wired to CTS 8 CTS Handshake; hard-wired to RTS 9 None Unused Serial Communications J3 is an RS-232 serial port, designed to be compatible with the IBM PC 9-pin serial port. Use a straight-through DB9 male-to-female cable to connect J3 to this port. If the only available serial port has a 25-pin connector, you may use a standard 25-pin to 9-pin adapter. Table 9 shows the pinout of J3. The MAX233 is an RS-232 interface voltage level shifter with two transmitters and two receivers. It includes a built-in charge pump with internal capacitors that generates the output voltages necessary to drive RS-232 lines. 40-Pin Data Connector J1 The 20 x 2 pin header connects the 68HC16 module to a Maxim EV kit. Table 10 lists the function of each pin. Note that 68HC16 object code is not compatible with 68HC11 object code. Use the 68HC16 module only with those modules that are designed to support it, and only download code that is targeted for the 68HC16 module. Downloading incorrect object code into the 68HC16 module will have unpredictable results. Address Ranges The 68HC16 C generates various enable signals for different address ranges. The ROM and RAM enable signals are fed directly to the respective chips. Several additional signals (J1.11-J1.14) are available on the data connector to be used by Maxim EV kits. Table 11 outlines the address ranges for each of the elements found on the 68HC16 module, and Table 12 is a truth table that describes the logic for each of the 68HC16's chip-select outputs. Because the addresses are not completely decoded, the boot ROM and user RAM have shadows. 16 Table 10. 40-Pin Data-Connector Signals PIN 1-4 5, 6 7, 8 9 10 11 12 13 14 15 16 17 18 19 20-26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 NAME GND VPREREG VCC RD WR 7E000 7E800 7F000 7F800 A00 A01 A02 A03 EXTD0 EXTD1-7 IC1 IC2 IC3 OC1 OC2 OC3 OC4 IC4 MISO MOSI SCK PCS0/SS CLKOUT PWMA FUNCTION Ground Unregulated input voltage +5V from on-board regulator Read strobe Write strobe Chip select for 7E000-7E7FF Chip select for 7E800-7EFFF Chip select for 7F000-7F7FF Chip select for 7F800-7FFFF Address bit 0 (LSB) Address bit 1 Address bit 2 Address bit 3 Buffered data bus 0 (LSB) Buffered data bus bits 1-7 General I/O port bit 0 (LSB) General I/O port bit 1 General I/O port bit 2 General I/O port bit 3 General I/O port bit 4 General I/O port bit 5 General I/O port bit 6 General I/O port bit 7 QSPI master-in, slave-out QSPI master-out, slave-in QSPI serial clock QSPI chip-select output System clock output Pulse-width-modulator output ______________________________________________________________________________________ MAX194 Evaluation System/Evaluation Kit PIN FUNCTION 00000-07FFF Boot ROM (U3, strobed by CSBOOT) 08000-0FFFF Shadow of boot ROM 10000-17FFF User RAM (U5, strobed by CS0 and CS2) 18000-1FFFF Shadow of user RAM Boot ROM The boot ROM, U3, is configured as an 8-bit memory device. Resistor R4 pulls data bit 0 low during system reset, forcing the C to fetch instructions using only the upper eight data bits. The boot ROM checks the system and waits for commands from the host. Refer to the EV kit manual for specific start-up procedures. Software 20000-203FF Internal standby RAM; 1kbyte 20400-7DFFF Unused 7E000-7E7FF External chip select (J1 pin 11) (CS7) All software is supplied on a disk with the EV kit. Instructions for operating the software are included in the EV kit manual. Refer to the EV kit manual for more information. 7E800-7EFFF External chip select (J1 pin 12) (CS8) _______68HC16 Module Self Check 7F000-7F7FF External chip select (J1 pin 13) (CS9) 7F800-7FFFF External chip select (J1 pin 14) (CS10) 80000-F7FFF Not accessed by the 68HC16 F8000-FF6FF Unused FF700-FF73F 68HC16's built-in ADC (not used) FF740-FF8FF Unused FF900-FF93F General-purpose timer module (GPT) To test the 68HC16 module's integrity, connect the power supply to the power terminals (J2). Do not connect anything to J1 or J3. Slide the power switch SW1 to the "ON" position. The LED will light up, and will flash within 5 seconds. If the LED flashes with a 50%-on/50%-off duty cycle, then it passed its self check. Note that this test does not exercise the RS-232 port or the EV kit 40-pin interface, but it does confirm that the power supply, microprocessor, ROM, and RAM passed the self test. If the LED flashes with a 10%-on/90%-off duty cycle, then it failed its self check. Most likely, the RAM chip (U5) is bad. If the LED remains on and does not flash, then the problem is either U3 (the EPROM), U1 (the microprocessor), U4 (the regulator), the MAX707 reset generator, or the power supply. Use a voltmeter to verify that the power supplies are good. Check the powersupply input and the +5V output from the regulator. Use an oscilloscope to see if the 32.768kHz reference oscillator is running. FF940-FF9FF Unused FFA00-FFA7F System integration module (SIM) FFA80-FFAFF Unused FFB00-FFB07 Internal standby RAM (SRAM) control registers FFB08-FFBFF Unused FFC00-FFDFF Queued serial module (QSM) FFE00-FFFFF Unused ______________________________________________________________________________________ 17 Evaluates: MAX194/MAX195 Table 11. 68HC16 Module Memory Map (all address values are in 20-bit hex) Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit Table 12. 68HC16 Chip-Select Outputs Truth Table ADDRESS RANGE CSBOOT CS0 CS1 CS2 CS5 CS6 CS7 CS8 CS9 CS10 0xxxx read L H H H H H H H H H 1xxxx read H H H L H H H H H H 1xxxx write H L H H H H H H H H 7E0xx read H H L H H L L H H H 7E0xx write H H H H L L L H H H 7E8xx read H H L H H L H L H H 7E8xx write H H H H L L H L H H 7F0xx read H H L H H L H H L H 7F0xx write H H H H L L H H L H 7F8xx read H H L H H L H H H L 7F8xx write H H H H L L H H H L VCC LED1 R5 470 GROUND PWMB C13 0.1F VCC UNREGULATED 7V TO 20V REGULATED +5V INTEL COMPATIBLE READ/WRITE STROBES GND CS6/IOBUFFER CS1/RDIO 19 1 D08 D09 D10 D11 D12 D13 D14 D15 2 3 4 5 6 7 8 9 CHIP SELECTS OE DIR LOW ADDRESS BITS U6 74HCT245 B1 B2 B3 B4 B5 B6 B7 B8 A1 A2 A3 A4 A5 A6 A7 A8 18 17 16 15 14 13 12 11 EXTD0 EXTD1 EXTD2 EXTD3 EXTD4 EXTD5 EXTD6 EXTD7 8-BIT BUFFERED BIDIRECTIONAL DATA BUS 8-BIT GENERAL I/O PORT HIGH-SPEED SERIAL INTERFACE (QSM/QSPI) VCC 1 2 3 4 R6 10k SIP RESISTOR 5 6 7 8 9 10 GND GND VPREREG VCC CS1/RDIO CS7/7E000 CS9/7F000 A00 A02 EXTD0 EXTD2 EXTD4 EXTD6 IC1 IC3 OC2 OC4 MISO SCK CLKOUT J1-1 J1-3 J1-5 J1-7 J1-9 J1-11 J1-13 J1-15 J1-17 J1-19 J1-21 J1-23 J1-25 J1-27 J1-29 J1-31 J1-33 J1-35 J1-37 J1-39 J1-2 J1-4 J1-6 J1-8 J1-10 J1-12 J1-14 J1-16 J1-18 J1-20 J1-22 J1-24 J1-26 J1-28 J1-30 J1-32 J1-34 J1-36 J1-38 J1-40 TSTME BKPT/DSCLK BKPT/DSCLK HALT DS J4-1 J4-2 BERR BERR GND J4-3 J4-4 BKPT/DSCLK MODCLK GND J4-5 J4-6 FREEZE DSACK1 RESET J4-7 J4-8 IPIPE1/DSI VCC J4-9 J4-10 IPIPE0/DS0 DSACK0 IRQ7 Figure 5. 68HC16 Module Schematic 18 ______________________________________________________________________________________ GND GND VPREREG VCC CS5/WRIO CS8/7E800 CS10/7F800 A01 A03 EXTD1 EXTD3 EXTD5 EXTD7 IC2 OC1 OC3 IC4 MOSI PCSO/SS PWMA MAX194 Evaluation System/Evaluation Kit Evaluates: MAX194/MAX195 VSSE C14 0.1F C8 0.01F VCC RXD PCS3 PCS2 PCS1 PCS0/SS SCK MOSI MISO VSSE VDDE IC1 IC2 IC3 OC1 OC2 VSSI VDDI OC3 OC4 IC4/OC5 PAI PWMA PWMB PCLK VSSE VDDE ADDR23 ADDR22 ADDR21 ADDR20 ADDR19 BGACK BG TXD ADDR1 ADDR2 VDDE VSSE ADDR3 ADDR4 ADDR5 ADDR6 ADDR7 ADDR8 VSSI ADDR9 ADDR10 ADDR11 ADDR12 ADDR13 ADDR14 ADDR15 ADDR16 ADDR17 ADDR18 VDDE VSSE VDDA VSSA ADA0 ADA1 ADA2 ADA3 ADA4 ADA5 VRH BR FC2 FC1 VDDE VSSE FCO CSBOOT DATA0 DATA1 DATA2 DATA3 VSSI DATA4 DATA5 DATA6 DATA7 DATA8 DATA9 VDDE VSSE DATA10 DATA11 DATA12 DATA13 DATA14 DATA15 ADDRO DSACK0 DSACK1 AVEC DS AS VDDE U1 MOTOROLA MC68HC16Z1CFC16 116 115 114 113 112 111 110 109 108 107 106 105 104 103 102 101 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 CSO/WRRAM CS5/WRIO VCC VSSE CSBOOT/RDROM DOO VSSI DO8 DO9 VCC VSSE D10 D11 D12 D13 D14 D15 AOO DSACKO DSACK1 DS VCC 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 VSSE 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 VRL ADA6 ADA7 VSTBY XTAL VDDSYN EXTAL VSSI VDDI XFC VDDE VSSE CLKOUT FREEZE/QUOT TSTME/TSC BKPT/DSCLK IPIPE0/DS0 IPIPE1/DS1 RESET HALT BERR IRQ7 IRQ6 IRQ5 IRQ4 IRQ3 IRQ2 IRQ1 MODCLK R/W SIZ1 SIZ0 VSSE A01 A02 VCC VSSE A03 A04 A05 A06 A07 A08 VSSI A09 A10 A11 A12 A13 A14 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 132 131 130 129 128 127 126 125 124 123 122 121 120 119 118 117 RXD TXD VCC CS10/7F800 CS9/7F000 CS8/7E800 CS7/7E000 CS6/IOBUFFER CS2/RDRAM CS1/RDIO PWMA PWMB VSSE VCC IC1 IC2 IC3 OC1 OC2 VSSI VDDI OC3 OC4 IC4 MISO MOSI SCK PCSO/SS L2 10H OPTIONAL C3 1F 20V C10 0.1F VSSE MODCLK VCC VCC VSSE CLKOUT FREEZE TSTME BKPT/DSCLK IPIPEO/DS0 IPIPE1/DSI RESET HALT BERR IRQ7 XTAL VSTBY EXTAL VSSI VDDI JU4 VSSE VSSI Figure 5. 68HC16 Module Schematic (continued) ______________________________________________________________________________________ 19 Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit VCC R2 330k XTAL C7 22pF VCC R1 10M Y1 32.768kHz J3-7 RTS T1IN T1OUT 5 1 T2IN T2OUT 18 3 R1OUT R1IN 4 20 R2OUT R2IN 19 2 TXD EXTAL C6 22pF J3-8 CTS 7 VCC GND J3-2 RXD 2 VCC RXD U7 MAX707 SW2 RESET 5 PFO 1 6 N.C. MR 8 RESET 4 7 RESET PFI GND J2 + - 8 13 C1+ C1- C2+ 15 C2+ U2 MAX233 V17 V14 V+ 3 GND 11 12 RESET J3-3 TXD J3-4 DTR 10 C216 C2- GND GND 9 6 J3-6 DSR J3-1 DCD SW1 POWER J3-5 GND JU5 D1 1N4001 OUT C4 22F 25V 2 A(00:18) RESET R3 10k D09 RESET C1 OPTIONAL 1F 20V VCC GND R4 10k D00 VCC 3 A00 A01 A02 A03 A04 A05 A06 A07 A08 A09 A10 A11 A12 A13 A14 GND CS2/RDRAM CS0/WRRAM 10 9 8 7 6 5 4 3 25 24 21 23 2 26 1 20 22 27 C2 1F 20V VDDI VSSI JU3 VSSE A0 A1 U5 A2 62256 A3 A4 A5 A6 A7 A8 A9 A10 A11 A12 A13 A14 I/O0 I/O1 I/O2 I/O3 I/O4 I/O5 I/O6 I/O7 11 12 13 15 16 17 18 19 D08 D09 D10 D11 D12 D13 D14 D15 VCC C12 0.1F VCC CSBOOT/RDROM CS OE WE 2 A14 32k x 8-BIT HIGH-SPEED CMOS STATIC RAM A00 A01 A02 A03 A04 A05 A06 A07 A08 A09 A10 A11 A12 A13 1 3 10 9 8 7 6 5 4 3 25 24 21 23 2 26 27 1 22 20 A0 A1 U3 A2 27C256 A3 A4 A5 A6 A7 A8 A9 A10 A11 A12 A13 DQ0 DQ1 DQ2 DQ3 DQ4 DQ5 DQ6 DQ7 A14 VPP OE CE VCC 32k x 8-BIT CMOS EPROM Figure 5. 68HC16 Module Schematic (continued) 20 11 12 13 15 16 17 18 19 ______________________________________________________________________________________ D08 D09 D10 D11 D12 D13 D14 D15 D(00:15) IN A(00:18) C5 22F 20V L1 10H U4 78M05 D(00:15) 1 J3-9 RI VSSE GND VPREREG VCC C11 0.1F MAX194 Evaluation System/Evaluation Kit Evaluates: MAX194/MAX195 Figure 6. 68HC16 Module Component Placement Guide--Component Side ______________________________________________________________________________________ 21 Evaluates: MAX194/MAX195 MAX194 Evaluation System/Evaluation Kit Figure 7. 68HC16 Module PC Board Layout--Component Side 22 ______________________________________________________________________________________ MAX194 Evaluation System/Evaluation Kit Evaluates: MAX194/MAX195 Figure 8. 68HC16 Module PC Board Layout--Solder Side 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 __________________ 23 (c) 1995 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products.