19-2602 Rev 0; 10/02 MAX3669ETG Evaluation Kit Features Fully Assembled and Tested +3.3V or +5V Operation On-Board Input Termination Independent Electrical Monitoring of Modulation and Bias Currents Component Suppliers SUPPLIER PHONE FAX Ordering Information AVX 843-448-9411 843-448-1943 Coilcraft 847-639-6400 847-639-1469 PART TEMP RANGE IC PACKAGE Murata 770-436-1300 770-436-3030 MAX3669ETGEVKIT -40C to +85C 24 QFN Zetex 631-360-2222 631-360-8222 Note: Please indicate that you are using the MAX3669ETG when contacting these component suppliers. Component List for Electrical Configuration DESIGNATION QTY DESCRIPTION DESIGNATION QTY R6, R7, R21 3 DESCRIPTION 84.5 1% resistors (0603) 5 0.01F 10% ceramic capacitors (0402) R8, R9 2 124 1% resistors (0603) C4, C7, C10, C11 4 1F 10% ceramic capacitors (0603) R10, R11 2 20 1% resistors (0402) R12 1 10 1% resistor (0402) C5 1 Do not install R13, R22 2 0 resistors (0603) C8 1 100pF 10% ceramic capacitor (0402) R14 1 50k variable resistor Bourns 3296W C16 1 0.1F 10% ceramic capacitor (0603) R15 1 200k variable resistor Bourns 3296W C19 1 10F 10%, 10V min tantalum capacitor, case B AVX TAJC106K016 R16 1 100k variable resistor Bourns 3296W R18 1 110 5% resistor (0603) C21 1 5pF 5% ceramic capacitor (0402) R20 1 0 resistor (0402) C1, C2, C6, C12, C20 D1 1 LED R23 1 15 5% resistor (0603) J1, J2, J3 3 SMA connectors, edge mount R26, R28 2 392 1% resistors (0402) L3 1 1.2H inductor Coilcraft 1008LS-122XKBC R27, R29 2 Do not install P1 1 2-pin header, 0.1in centers 10 Test points None 1 Shunt for P1 VCC, GND, TP1, TP4, TP5, TP6, TP8-TP11 Q1 1 PNP transistor Zetex FMMT591A U1 1 MAX3669ETG (24-pin QFN) R1, R2, R24 3 1.5k 5% resistors (0402) R3 1 1k 5% resistor (0603) R5 1 12.4 1% resistor (0402) U3 1 MAX495ESA (8-pin SO) None 1 MAX3669 data sheet None 1 MAX3669ETG EV kit PC board, rev A ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. 1 Evaluates: MAX3669ETG General Description The MAX3669ETG evaluation kit (EV kit) is an assembled demonstration board that provides easy optical or electrical evaluation of the MAX3669ETG, a 622Mbps laser driver with current monitors and automatic power control (APC) circuitry. Although the MAX3669ETG EV kit is shipped in the electrical configuration, this EV kit also provides configuration instructions for optical operation. Evaluates: MAX3669ETG MAX3669ETG Evaluation Kit Component Modifications for Optical Configuration DESIGNATION QTY J3 1 Remove DESCRIPTION L2 1 Ferrite bead Murata BLM18HG601SN1 R5 1 Remove R13 1 Remove R19 1 20 5% resistor (0402) R20 1 5 5% resistor (0402) R22 1 Remove R23 1 Remove U2 1 User-supplied laser diode Optical Setup For optical operation, the electrical APC test circuit must be disabled. For optical evaluation of the MAX3669ETG, configure the EV kit as described in Component Modifications for Optical Configuration: 1) Remove the shunt from P1 to enable the output. Quick Start 2) Connect a TO-style header laser and monitor diode (Figure 1) as follows: Electrical Setup (Default) * Keeping the leads to the laser diode as short as possible, connect the laser diode on the component side of the board between R20 and VCC with the cathode connected to R20 and the anode connected to VCC. * Connect the monitor diode on the underside of the the board with the anode connected to the MAX3669ETG's MD pin and the cathode connected to VCC. Note: When performing resistance checks, manually set the ohmmeter to a high range to avoid forward biasing the on-chip ESD protection diodes. In the electrical configuration, an APC test circuit is included to emulate a semiconductor laser with a monitor photodiode. Monitor diode current is provided by Q1, which is controlled by an operational amplifier (U3). The APC test circuit, consisting of U3 and Q1, applies the simulated monitor diode current to the MAX3669ETG's MD pin. The ratio of IBIAS / IMD is R24 / R23 = 100. To ensure proper operation in the electrical configuration, set up the evaluation board as follows: 1) Verify inductor L2 is not installed. 2) Remove the shunt from P1 to enable the output. Note: When performing the following resistance checks, manually set the ohmmeter to a high range to avoid forward biasing the on-chip ESD protection diodes. 3) Adjust R14, the MOD (RMODSET) potentiometer, for 10k resistance between pins 2 and 3 (test point 5 and ground). 4) Adjust R15, the BIAS (RBIASMAX) potentiometer, for 10k resistance between pins 2 and 3 (test point 4 and ground). 5) Adjust R16, the APC (RAPCSET) potentiometer, for 10k resistance between pins 2 and 3 (test point 6 and ground). 6) Power up the board with a +3.3V supply. 7) Apply a differential input signal (max amplitude 800mV per side) to J1 and J2 (DATA+ and DATA-). 2 8) Attach a high-speed oscilloscope with 50 inputs to J3. 9) Adjust RBIASMAX (R15) and RAPCSET (R16) until the desired laser-bias current is achieved (refer to the note in the Applications Information section of the MAX3669 data sheet). 10) Adjust RMODSET (R14) until the desired laser-modulation current is achieved. Note: See the Adjustment and Control Descriptions table. 3) Adjust R14, the MOD (RMODSET) potentiometer, for maximum resistance between pins 2 and 3 (test point 5 and ground). 4) Adjust R15, the BIAS (RBIASMAX) potentiometer, for maximum resistance between pins 2 and 3 (test point 4 and ground). 5) Adjust R16, the APC (RAPCSET) potentiometer, for desired optical power. (Refer to the Design Procedure section of the MAX3669 data sheet.) 6) Power up the board with a +3.3V supply. 7) Apply a differential input signal (800mV per side) to J1 and J2 (DATA+ and DATA-). 8) Attach the laser-diode output to an optical/electrical converter. _______________________________________________________________________________________ MAX3669ETG Evaluation Kit 10) Adjust R14 until the desired optical amplitude is achieved. Optical amplitude can be observed on an oscilloscope connected to an optical/electrical converter. Adjustment and Control Descriptions See Quick Start first. COMPONENT NAME FUNCTION D1 APC Fail Indicator LED Refer to the Design section of the MAX3669 data sheet. Set APC current; then increase bias current until LED goes off (LED is illuminated when the APC loop is open and off when the APC loop is closed). J3 Electrical Output SMA Electrical output. Remove for optical operation. P1 OUTPUT DISABLE R14 RMODSET Laser modulation current adjustment R15 RBIASMAX Laser-bias current adjustment. In open-loop mode, R15 adjusts the laser-bias current. In closed-loop operation, R15 adjusts the maximum laser-bias current. R16 RAPCSET Automatic power-control adjustment. For closed-loop operation, R16 adjusts the monitor-diode current level. TP1 Fail Indicator Test Point Enable/disable the output currents. Shunting disables the part. Remove shunt for normal operation. TTL low level indicates a failure in the APC loop. _______________________________________________________________________________________ 3 Evaluates: MAX3669ETG 9) Adjust R15 until LED D1 is no longer illuminated. Laser power can be monitored at the laser diode with an optical/electrical converter (refer to the note in the Applications Information section of the MAX3669 data sheet). Evaluates: MAX3669ETG MAX3669ETG Evaluation Kit CONFIGURATION 1 CONFIGURATION 2 TOP OF PC BOARD TOP OF PC BOARD L2 VCC VCC L2 VCC VCC D3 D3 TO-46 CAN LASER/PHOTODIODE PAIR LD TO-46 CAN LASER/PHOTODIODE PAIR LD BOTTOM OF PC BOARD PD BOTTOM OF PC BOARD PD SOLDER BRIDGES VCC VCC VCC SOLDER BRIDGES CONFIGURATION 4 CONFIGURATION 3 TOP OF PC BOARD TOP OF PC BOARD VCC VCC D3 D3 TO-46 CAN LASER/PHOTODIODE PAIR LD BOTTOM OF PC BOARD SOLDER BRIDGES L2 L2 VCC VCC VCC PD VCC VCC LD TO-46 CAN LASER/PHOTODIODE PAIR BOTTOM OF PC BOARD SOLDER BRIDGES PD VCC VCC Figure 1. Attachment of Laser Diode/Monitor Diode to MAX3669ETG EV Kit 4 _______________________________________________________________________________________ _______________________________________________________________________________________ DATA- DATA+ J2 J1 GND VCC P5 P4 C11 1F R6 84.5 C10 1F R8 124 VCC R9 124 R7 84.5 L3 1.2H R21 84.5 VCC C2VCC R29 OPEN C19 C12 10F 0.01F C20 0.01F R27 OPEN TP11 TP8 0.01F R26 392 R28 392 VCC VCC VCC CW 6 5 4 3 2 1 P1 7 MODMON BIASMON GND DATA- DATA+ VCC VCC 8 23 TP5 22 R2 1.5k U1 21 20 R3 1.0k TP6 TP1 9 D1 RED 10 C5 OPEN 11 MAX3669ETG R18 110 BIASMAX ENABLE 24 R1 1.5k TP4 MODSET GND R15 200k RBIASMAX GND FAIL CW APCSET N.C. R14 50k RMODSET 19 VCC MD 12 MD VCC VCC OUT+ OUT- VCC R13 0 Q1 3 2 1 6 VCC VCC R11 2 7 1F C4 R22 0 TP9 TP10 C7 1F 10 R12 C8 100pF R23 15 VCC L2 OPEN C6 0.01F U3 3 4 20 R10 20 BIAS VCC BIAS 13 14 15 16 17 18 C1 0.01F C16 0.1F GND R24 1.5k CAPC GND CW VCC BIAS C21 5pF R19 OPEN R20 0 J3 R5 12.4 MD OUT Evaluates: MAX3669ETG R16 100k RAPCSET MAX3669ETG Evaluation Kit Figure 2. MAX3669ETG EV Kit Schematic--Electrical Configuration 5 DATA- DATA+ J2 J1 Figure 3. MAX3669ETG EV Kit Schematic--Optical Configuration _______________________________________________________________________________________ GND VCC P5 P4 C11 1F R6 84.5 C10 1F R8 124 VCC R9 124 R7 84.5 L3 1.2H R21 84.5 VCC C2VCC R29 OPEN C19 C12 10F 0.01F C20 0.01F R27 OPEN TP11 TP8 0.01F R26 392 R28 392 VCC CW 6 5 4 3 2 1 P1 7 MODMON BIASMON GND DATA- DATA+ VCC VCC 8 23 TP5 22 R2 1.5k U1 21 20 R3 1.0k TP6 TP1 9 D1 RED 10 C5 OPEN 11 MAX3669ETG R18 110 BIASMAX ENABLE 24 R1 1.5k TP4 MODSET GND R15 200k RBIASMAX VCC VCC CW FAIL R14 50k RMODSET APCSET N.C. CW 19 VCC MD 12 MD VCC VCC OUT+ OUT- VCC R13 OPEN Q1 3 2 1 6 VCC VCC L2 1F C4 7 C6 0.01F 4 2 U3 3 TP10 R22 OPEN R23 TP9 OPEN VCC C7 1F 10 R12 C8 100pF MURATA BLM18HG601SN1 20 R10 20 R11 BIAS VCC BIAS 13 14 15 16 17 18 C1 0.01F C16 0.1F GND R24 1.5k CAPC GND R16 100k RAPCSET VCC BIAS 6 GND C21 5pF R19 20 R20 5 R5 OPEN VCC MD Evaluates: MAX3669ETG MAX3669ETG Evaluation Kit MAX3669ETG Evaluation Kit Evaluates: MAX3669ETG 1.0" 1.0" Figure 4. MAX3669ETG EV Kit Component Placement Guide-- Component Side 1.0" Figure 5. MAX3669ETG EV Kit PC Board Layout--Component Side 1.0" Figure 6. MAX3669ETG EV Kit PC Board Layout--Solder Side Figure 7. MAX3669ETG EV Kit PC Board Layout--Ground Plane _______________________________________________________________________________________ 7 Evaluates: MAX3669ETG MAX3669ETG Evaluation Kit 1.0" Figure 8. MAX3669ETG EV Kit PC Board Layout--Power Plane 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) 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.