19-2388; Rev 0; 4/02 MAX3274 Evaluation Kit Features ♦ Test Points for Easy Monitoring of LOS and LOS ♦ Separate Pullup Supply (VLOS) Pin for LOS and LOS Outputs ♦ Jumpers Allow Quick Selection for Loss-of-Signal Threshold Level, Squelch, and Bandwidth Component List DESIGNATION QTY C1, C4 2 33µF ±10%, 10V min tantalum capacitors (case B) C2, C5–C15 12 0.1µF ±10%, 10V min ceramic capacitors (0402) C3 1 0.1µF ±10%, 10V min ceramic capacitor (0603) J1–J8 8 SMA connectors, edge mount, tab centers EFJohnson 142-0701-851 JU1–JU4, JU6, JU7 6 2-pin headers, 0.1in centers JU1–JU4, JU6, JU7 6 Shunts L1 1 Ordering Information PART TEMP RANGE MAX3274EVKIT 0°C to +85°C DESCRIPTION 4.7µH inductor Coilcraft 1008CT-040XKBC (1008) R1, R2, R6, R8 4 4.7kΩ ±5% resistors (0402) R3 1 1.5kΩ ±1% resistor (0402) R4 1 681Ω ±1% resistor (0402) R5 2 401Ω ±1% resistor (0402) R9, R10 2 Open TP1, TP2, GND, VCC, VLOS 5 Test points Digi-Key 5000K-ND U1 1 MAX3274UGE (MAX3274EVKIT) None 1 MAX3274, rev B, EV kit circuit board None 1 IC PACKAGE 16 QFN Component Suppliers PHONE FAX AVX SUPPLIER 803-946-0690 803-626-3123 Coilcraft 847-639-6400 847-639-1469 Murata 770-436-1300 770-436-3030 Venkel 800-950-8365 512-794-0087 MAX3274 data sheet ________________________________________________________________ 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: MAX3274 General Description The MAX3274 evaluation kit (EV kit) simplifies evaluation of the MAX3274 limiting amplifier. The EV kit allows quick threshold level selections, provides appropriate impedance matching circuitry, and includes calibration circuits. The MAX3274 EV kit is fully assembled and tested. Evaluates: MAX3274 MAX3274 Evaluation Kit Quick Start 1) Connect OUT+ and OUT- to a 50Ω terminated oscilloscope. 2) Connect IN+ and IN- to a 500mVP-P, 2.125Gbps differential data stream. Calibration Strip The calibration strip can be used to calibrate out the effects of the circuit board, such as connectors, in critical measurements such as deterministic jitter and rise/fall times. 3) Remove jumper JU6 to disable squelch. 4) Connect shunt at jumper JU7 to use VCC as the pullup supply for LOS and LOS outputs. 5) Connect shunt at jumper JU4 for 2.125Gbps operation. 6) Connect a +3.3V power supply to the VCC pad, and then connect the power-supply ground to the GND pad. 7) Observe a limited signal at the output (~1.1VP-P differential for the MAX3274). Table 1. Jumpers NAME JU1, JU2, JU3 Select loss-of-signal threshold level JU4 Selects input bandwidth, open for 1.0625Gbps and closed for 2.125Gbps JU6 Closed to enable squelch, opened to disable squelch JU7 When using an external pullup supply for LOS and LOS other than VCC, remove jumper Detailed Description The MAX3274 dual-rate limiting amplifier is designed to accept a differential signal from a 100Ω differential output transimpedance preamplifier. In order for output data to be valid, incoming data must be above the threshold voltage set by placing a shunt at jumper JU1, JU2, or JU3. LOS and LOS are open-collector outputs and indicate whether the input data stream voltage is below the threshold voltage. The EV kit supplies the required pullup resistors for LOS and LOS. Placing a shunt at jumper JU6 enables squelch and disables output if incoming data voltage is below the threshold level. The shunt can be removed from jumper JU7 if the user wants to interface the LOS and LOS pins with a voltage different from VCC. With a shunt at jumper JU4, the input filter is disabled and the chip is ready to accept data at 2.125Gbps. To evaluate the chip at 1.0625Gbps, remove the shunt at jumper JU4. 2 FUNCTION _______________________________________________________________________________________ MAX3274 Evaluation Kit VLOS JU7 C1 33µF C2 0.1µF C5 0.1µF C6 0.1µF Evaluates: MAX3274 L1 4.7µH VCC C7 0.1µF C4 33µF C3 0.1µF GND R1 4.7kΩ R2 4.7kΩ TP1 16 SMA J1 IN+ GND C8 0.1µF 1 TP2 15 14 LOS 13 LOS GND C10 0.1µF OUT+ IN+ 12 C9 0.1µF R10* 2 INSMA J2 3 4 IN- OUT- U1 MAX3274 VCC VCC BWSEL TH TEST 5 JU4 NC R8 4.7kΩ SQUELCH 6 VCC GND 7 8 SMA J3 OUT+ C11 0.1µF 11 OUTSMA J4 10 9 R3 1.5kΩ R4 681Ω R5 401Ω JU1 JU2 JU3 JU6 R6 4.7kΩ C13 0.1µF SMA J6 C15 0.1µF SMA J8 CALIBRATION STRIP R10*- OPEN R9 OPEN C12 0.1µF SMA J5 C14 0.1µF SMA J7 Figure 1. MAX3274 EV Kit Schematic _______________________________________________________________________________________ 3 Evaluates: MAX3274 MAX3274 Evaluation Kit Figure 2. MAX3274 EV Kit Component Placement Guide—Component Side 4 _______________________________________________________________________________________ MAX3274 Evaluation Kit Evaluates: MAX3274 Figure 3. MAX3274 EV Kit PC Board Layout—Component Side Figure 4. MAX3274 EV Kit PC Board Layout—Ground Plane Figure 5. MAX3274 EV Kit PC Board Layout—Power Plane Figure 6. MAX3274 EV Kit 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. 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