Evaluate: MAX4444/MAX4445 19-1585 Rev 0 10/99 MAX4444 Evaluation Kit General Description Features The MAX4444 evaluation kit (EV kit) simplifies evalua- 500MHz Full-Power Bandwidth tion of the MAX4444 ultra-fast differential line receiver. 5000V/s Slew Rate The EV kit includes the MAX4444, which has a fixed gain of +2V/V. This EV kit can also be used to evaluate Proven PC Board Layout the adjustable-gain MAX4445, which is stable with a Fully Assembled and Tested Surface-Mount Board minimum gain of +2V/V. To evaluate the MAX4445, order a free sample of the MAX4445ESE along with the MAX4444 EV kit. Ordering Information PART TEMP. RANGE IC PACKAGE Component List MAX4444EVKIT 0C to +70C 16 SO DESIGNATION QTY DESCRIPTION 4.7F 20%, 10V tantalum capacitors C1, C3 2 AVX TAJA475M010R Quick Start C2, C4 2 0.1F ceramic capacitors The MAX4444 EV kit is fully assembled and tested. Follow these steps to verify board operation. Do not turn R1, R2, R3 3 49.9 1% resistors on the power supply until all connections are com- R4 1 1M 5% resistor pleted. 1) Connect a +5V power supply to the V pin and a -5V CC R 0 Not installed G power supply to the V pin. Connect power-supply EE JU1 1 2-pin header ground to the GND pads. 2) Ensure that the shunt is installed on jumper JU1. None 1 Shunt (JU1) 3) Apply signals to IN+ and IN- whose differential volt- IN-, IN+, OUT 3 SMA connectors age does not exceed 1.5V. These signals must not U1 1 MAX4444ESE (16-Pin SO) exceed the amplifiers input common-mode range of -2.9V to +2.9V. None 1 MAX4444 EV kit PC board 4) Connect the output marked OUT to a 50 terminated None 1 MAX4444 EV kit data sheet oscilloscope input. 5) Turn on the power supply and verify the output signal None 1 MAX4444/MAX4445 data sheet on the oscilloscope. The output amplitude observed on the oscilloscope will be the same as the amplitude of the differential input. This is due to the multiplica- tion of the gain of +2V/V with the voltage divider formed by the 49.9 back-terminating resistor (R3) Component Supplier and the oscilloscope input termination. SUPPLIER PHONE FAX AVX 803-946-0690 803-626-3123 Note: Please indicate that you are using the MAX4444 or MAX4445 when contacting the above component supplier. Maxim Integrated Products 1 For free samples & the latest literature: MAX4444 Evaluation Kit Detailed Description Table 1. Jumper JU1 Functions MAX4444 MAX4444 Enable Control SHUNT ENABLE PIN OUTPUT The MAX4444 provides an enable pin (EN) to enable or disable the output. Table 1 lists the options available for Installed Connected to VCC MAX4444 enabled the enable/disable control jumper (JU1). EN is a TTL/CMOS-logic level input. Pulled to GND through MAX4444 in shut- Not installed 1M resistor (R4) down Layout Considerations The MAX4444 EV kit layout has been optimized for high-speed signals, with careful attention given to Evaluating the MAX4445 grounding, power-supply bypassing, and signal-path To evaluate the MAX4445, turn off the power to the EV kit. layout. The small, surface-mount, ceramic bypass Replace the MAX4444 with a MAX4445ESE, and install capacitors (C2, C4) have been placed as close to the gain-setting resistor R (0805, 1%) according to the fol- G MAX4444 supply pins as possible. Signal traces have lowing formula: been kept as short as possible by using 0805-sized ter- mination and gain-set resistors. R = 600 / (gain - 1) G Note: The gain must be at least +2V/V (R 600) for G the amplifier to be stable. 1 16 VCC V GND CC C1 C2 2 V R3 4.7F 0.1F CC U1 49.9 10V 1% MAX4444 15 OUT OUT 3 IN- IN- R1 4 14 N.C. V EE 49.9 1% R G 13 OPEN V VEE EE 5 N.C. 12 6 V EE IN+ IN+ 11 R2 V EE 49.9 1% 10 REF 7 VCC V EE JU1 8 9 VEE V EN EE C3 C4 4.7F 0.1F R4 1M 10V GND Figure 1. MAX4444 EV Kit Schematic 2 Evaluate: MAX4444/MAX4445