The MAX3654 evaluation kit (EV kit) is a factory-assembled printed circuit board (PCB) that provides two circuit versions—optical input and electrical input.
The optical circuit includes the photodiode bias circuitry, an op amp for feed-forward AGC operation, and a balun for single-ended 75 output. Through-hole pads are provided to attach a triplexer analog photodiode. It is important to select a photodiode with capacitance and inductance in the anode and cathode connections as symmetric as possible for optimum linearity.
The electrical circuit is normally configured with a 50 input for use with conventional test and measurement equipment and a 75 output. The 75 output can be connected to 50 test and measurement equipment using a minimum loss pad. If desired, the MAX3654 input can also provide a 75 input by replacing R12 and R13 with 25 resistors.