The EV4816A-G-00A is an evaluation board for the MP4816A, a high voltage 16-channel analog switch. The MP4816A is designed for medical ultrasound application. It can also be used for non-destructive test (NDT) as the application is very similar to medical ultrasound.
The high voltage analog switches are used to multiplex the transmitter and receiver circuitries to different piezoelectric transducer (PZT) elements. The MP4816A has a resistor to ground on the output pins, SWout. This is to help ensure there is no significant DC voltage built up across the PZT element. The switches can be turned on/off via a serial 16-bit shift register. The serial control interface will help minimize the number of I/O connection.