Evaluates: MAX3656 19-2903 Rev 2 8/10 MAX3656 Evaluation Kit General Description Features The MAX3656 evaluation kit (EV kit) is an assembled S Fully Assembled and Tested demonstration board that provides optical evaluation of S Adjustable Laser Bias Current the MAX3656 155Mbps to 2.5Gbps burst-mode laser S Adjustable Laser Modulation Current driver. The evaluation board allows connection with S Single +3.3V Power-Supply Operation coaxial laser packages as well as BIDI packages. EV Kit Contents Ordering Information S MAX3656 EV Kit Board PART TYPE MAX3656EVKIT+ EV Kit +Denotes lead(Pb)-free and RoHS compliant. Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION JP26, JP28, 3-pin headers, 0.1in center 1FF Q10% ceramic capacitor 5 JP30, JP32, JP33 Sullins PEC36SAAN C1 1 (0402) Murata GRM155R61A105KE15D JP26, JP28, Shunts 5 JP30, JP32, JP33 Sullins SSC02SYAN 1000pF Q10% ceramic capacitor C2 1 (0402) 10nH Q5% inductor (0402) L1 1 Murata GRM155R71H102KA01D Murata LQG15HS10NJ02 npn transistor 0.1FF Q10% ceramic capacitors Q1 1 Zetex FMMT491ATA C3, C10C15 7 (0402) Murata GRM155R61A104KA01D R1 1 15I Q5% resistor (0402) R2, R3 2 10I Q5% resistors (0402) 10FF Q10% tantalum capacitor C19 1 (B case) R12, R126 2 5.6I Q5% resistors (0402) AVX TAJB106K010RNJ R43 1 200I Q5% resistor (0603) 50kI variable resistors 0.1FF Q10% ceramic capacitor R59, R79, R90 3 Bourns 3296W-1-503LF C20 1 (0603) Murata GRM188R71H104KA93D R61, R82, R118 0 Not installed, resistors (0603) R88 1 4.3kI Q5% resistor (0603) 0.01FF Q10% ceramic capacitor C21 1 (0603) R91, R92, R94, TDK C1005X8R1E103K R95, R97, R98, 0 Not installed, resistors (0402) R100, R101 27pF Q5% ceramic capacitor R103, R104 2 100I Q1% resistors (0402) C24 1 (0402) Murata GRM1555C1H270JZ01D R113R116 4 0I Q5% resistors (0402) R119 1 3kI Q5% resistor (0603) Green LED, SMD D2 1 Panasonic LNJ311G8PRA R120 1 1.5kI Q5% resistor (0603) R121 1 75I Q5% resistor (0402) Diodes D3, D4 2 Panasonic MA27P0100L Burst-mode laser driver D5 0 Laser, user supplied U1 1 (24 TQFN-EP*) Maxim MAX3656ETG+ J18, J20, TP1, Test points 4 TP2 Keystone 5000 PCB: MAX3656 EVALUATION 1 BOARD+, Rev D SMA connectors, edge mount, J23J26 4 tab contact *EP = Exposed pad. Johnson 142-0701-851 Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.MAX3656 Evaluation Kit 11) Turn on the power supply and adjust APCSET (R79) Quick Start for the desired average optical power, then adjust To evaluate the MAX3656 with a laser diode, configure MODSET (R59) for the desired extinction ratio. the EV kit as follows: Note: The APC loop is functional when the FAIL 1) Pull shunts off all jumpers (JP33, JP30, JP32, JP26, indicator, green LED D2, is on. The LED is off if the and JP28). BIASMAX is set too low, the monitor diode (MD) pin is not connected, or the modulation current is set too 2) Set R to 20kI by adjusting the APCSET APCSET high. variable resistor R79 until the measured resistance between the VAR pin of jumper JP33 and GND is 12) If the eye diagram contains too much overshoot or 20kI. Then install a shunt on the VAR side of jumper the rise/fall times are too slow, experimentally adjust JP33. the values of the RL peaking network (R3, L1) and RC shunt network (R121, C24) to better match the 3) Set R to 20kI by adjusting the MODSET MODSET characteristics of the laser. variable resistor R59 until the measured resistance between the VAR pin of jumper JP30 and GND is Applications Information 20kI. Then install a shunt on the VAR side of jumper JP30. Continuous Mode Operation For continuous mode operation, switch the differential 4) Set R to 7kI by adjusting the BIASMAX BIASMAX burst-enable input (BENQ) to a constant high in one of variable resistor R90 until the measured resistance two ways: between the VAR pin of jumper JP32 and GND is 7kI. Then install a shunt on the VAR side of jumper Remove resistor R103. Install a 1kI resistor on R101 JP32. and 3kI resistors on R91, R92, and R100. 5) Connect the EN pin to GND by installing a shunt on Connect a +2.3V supply to BEN+ and a +1.7V the GND side of jumper JP26. supply to BEN- (or a differential 0.6V supply between BEN+ and BEN-). 6) Connect the LONGB pin to GND by installing a shunt on the GND side of jumper JP28. LVPECL Input Terminations If needed, an LVPECL Thevenin equivalent load 7) Solder a laser to edge connection D5. See Figure 1 for a view of how the laser should be mounted on the termination of 50I to (V - 2V) can be created by doing CC the following: EV kit. Be sure to keep the laser leads as short as possible to minimize parasitic inductance. Remove resistors R103 and R104. 8) Connect a differential data source to IN+ (J26) and Solder 130I resistors on R92, R94, R98, and R101. IN- (J25) and a differential burst-enable source Solder 82I resistors on R91, R95, R97, and R100. to BEN+ (J24) and BEN- (J23). Make sure the For more information, refer to Application Note 291: differential signals are between 200mV and P-P HFAN-01.0: Introduction to LVDS, PECL, and CML. 1600mV and the common-mode is between P-P (V - 1.49V) and (V - V /4). See the Applications CC CC IN LVCMOS Burst Enable Information section for more options. To drive the burst-enable input (BEN+) with single- 9) Attach a +3.3V power supply to J18 (+3.3V) and J20 ended LVCMOS levels, do the following: (GND). Set the current limit to 250mA. Remove resistors R103 and R114. 10) Connect the output of the user-supplied laser Solder 3kI resistor on R114. to an optical-to-electrical converter that has the Solder 5kI resistors on R101 and R92. appropriate bandwidth (filter) for the intended application. Solder 9kI resistor on R91. 2 Evaluates: MAX3656