The ADC08131/ADC08134/ADC08138 are 8-bit successive approximation A/D converters with serial I/O and configurable input multiplexers with up to 8 channels. The serial I/O is configured to comply with the NSC MICROWIRETM serial data exchange standard for easy interface to the COPSTM family of controllers, and can easily interface with standard shift registers or microprocessors. All three devices provide a 2.5V band-gap derived reference with guaranteed performance over temperature. A track/hold function allows the analog voltage at the positive input to vary during the actual A/D conversion. The analog inputs can be configured to operate in various combinations