In ATE system, there are many functional cards like DPS, PE, PMU, HV PMU, Digitizer and AWG, RF, and so on. Each board has special testing functions. DPS is for supplying power to DUT. PE is integrated Pin driver and PPMU and active load to test many functions like pattern testing and open or short testing, and so on. PMU is testing DUT parameters, such as current or voltage. AWG is for generating arbitrary waveform to measuring like SNR, THD, audio performance, and so on.

There are many current or voltage signals that need to be sampled and measured in every function card. For example, in DPS or PMU, output voltage and current need to be measured. In PE, output voltage needs to be measured for calibration. There are also some general power supply must be monitored in every function board.