The OPA3S2859-EP can be configured as a non-inverting voltage amplifier, inverting voltage amplifier, or transimpedance amplifier. The configuration shown in Figure 2-1 shows the amplifier configured for a non-inverting input with a 1 k-Ω gain resistor on the COM pins and 1 k-Ω, 10 k-Ω, and 100 k-Ω resistor in the feedback network. A shorting stub must be placed on the COM pins SMA connectors to connect the feedback resistor to ground. This yields selectable non-inverting gains of 2 V/V, 11 V/V, and 101 V/V. The gain resistor can be connected through the COM or IN- pins for voltage gain configurations, but it is suggested to connect it through the COM pins for the best performance. The series resistors on the COM pins should be shorted and the current input connected through the respective COM pin input for transimpedance configurations. The EVM layout is optimized for voltage gain configurations to easily connect to the test equipment. It is best to build a new board design that locates the diode as close as possible to the COM input for transimpedance tests with a photodiode.