Evaluates: MAX40075/MAX40088/ MAX40088 Evaluation Kit MAX40079/MAX40087 General Description Quick Start The MAX40088 evaluation kit (EV kit) is a fully assem- Required Equipment bled and tested circuit board that contains all the Before beginning, the following equipment is needed: components necessary to evaluate the MAX40075/ MAX40088 EV kit MAX40088/MAX40079/MAX40087 ICs. The MAX40088 EV kit printed circuit board (PCB) comes installed with 2.7V to 5.5V, 100mA DC power supply MAX40088AUT+ in 6-SOT23 package. Precision voltage calibrator The device is a rail-to-rail output op amp offering 10MHz Digital multimeter Gain Bandwidth product (MAX40075/MAX40079) and 42MHz Gain Bandwidth product (MAX40088/MAX40087). Procedure The EV kit operates from a single 2.7V to 5.5V DC power The EV kit is fully assembled and tested. Follow the steps supply or from 1.35V to 2.75V split supply. below to verify board operation. Caution: Do not turn on power supplies until all connections Features are completed and turn on V , V supplies before turning DD SS +2.7V to +5.5V Supply Voltage Range across V DD on voltage calibrator on the input pins. and V SS 1) Make sure JU1 jumper is uninstalled and JU2 jumper 42MHz Gain Bandwidth Product (MAX40088/MAX40087), is in 1-2 position before applying supply voltage. Gain = 5V/V Stable 2) Connect positive terminal of the +5V supply to the 10MHz Gain Bandwidth Product (MAX40075/MAX40079), VDD test point and the GND terminal of supply to Gain = 1V/V Stable the GND test point. Make sure JU3 is in 1-2 position and JU4 is un-installed. JU4 is opened if split supply Ultra-Low Distortion (0.0002% with 1k load) operation is desired. Proven PCB Layout 3) Connect the positive terminal of the precision voltage Fully Assembled and Tested calibrator to the INP/TP3 test point. 4) Connect the DMM to monitor the voltage on the OUTA/TP11 test point. Ordering Information appears at end of data sheet. 5) Turn on the 5V power supply connected to VDD test point, turn on the precision voltage calibrator on INP/TP3 test point and set 0.1V. Observe the output at the OUTA/TP11 test point on the DMM. DMM should read approximately 1V. Also, vary IN+ voltage between 0V to 0.45V and see if DMM on OUTA test point is showing a gained up by voltage by 10V/V to the voltage applied on INP test point. Once above step is confirmed, EV kit is tested for functionality. 319-100058 Rev 1 12/17Evaluates: MAX40075/MAX40088/ MAX40088 Evaluation Kit MAX40079/MAX40087 where Detailed Description of Hardware The MAX40088 EV kit contains the MAX40088 IC, which R8 R2 GAIN is rail-to-rail output op amps with low noise and wide R9 R3 bandwidth in 6-SOT23 package. The EV kit operates from a single 2.7V to 5.5V DC power supply. The EV kit is Transimpedance Amplifier meant to work using split supplies as well where the volt- To configure the MAX40088 EV kit as a transimpedance age between V and V is +2.7V to +5.5V. DD SS amplifier (TIA), short jumper JU1 on 1-2, replace R3, R9 with a 0 ohm resistor and populate R8 pad with 100k Default Application Circuit resistor. The output voltage of the TIA is the input current The EV kit comes preconfigured in a Non-Inverting ampli - multiplied by the feedback resistor: fier configuration with Gain set as 10V/V. V = (I + I ) x R8 + V OUT INM BIAS- OS Op Amp Configurations where IINM is the input current source applied at the INM The EV kit provides flexibility to easily reconfigure the test point, IBIAS- is the input bias current into IN- pin, and op amp into any of the three common circuit topologies: V is the input offset voltage of the op amp. Use capaci- OS inverting amplifier, non-inverting amplifier and Differential tor C2 to stabilize the op amp by rolling off high-frequency amplifier. gain due to a large cable capacitance if desired. These configurations are described in the next few sections. Capacitive Loads Noninverting Configuration Some applications require driving large capacitive loads. The MAX40088 EV kit comes preconfigured as a non- To improve stability of the amplifier in such cases, replace inverting amplifier. The gain is set by the ratio of R8 and R11 with a suitable resistor value to improve amplifier R9. The MAX40088 EV kit comes preconfigured for a gain phase margin. of 10. The output voltage for the non-inverting configura - tion is given by the equation below: Table 1. Default Jumper Settings R8 V 1V+ SHUNT OUTA INP JUMPER DESCRIPTION R9 POSITION 1-2 IN+ to GND Inverting Configuration 2-3 IN+ terminated by 50 to GND To configure the EV kit as an inverting amplifier, remove JU1 the shunt 1-2 on JU2 and install a shunt on jumper JU1 Not Installed* IN+ terminal floating on position 1-2 and feed an input signal on the INM pad. 1-2* IN- to GND R8 VV= OUTA INM R9 2-3 IN- terminated by 50 to GND JU2 Not Installed IN- terminal floating Differential Amplifier To configure the MAX40088 EV kit as a differential 1-2* Device in active or normal mode amplifier, replace R2, R3, R8, and R9 with appropriate JU3 2-3 Device in Shutdown mode resistors. When R2 = R8 and R3 = R9, the CMRR of the Installed* Single-supply operation differential amplifier is determined by the matching of the JU4 resistor ratios R2/R3 and R8/R9. Not Installed Split-supply operation V = GAIN(V - V ) OUTA INP INM *Default position. Maxim Integrated 2 www.maximintegrated.com = = =