The AD7942 is a 14-bit， charge redistribution， successive approximation PulSAR? ADC that operates from a single power supply， VDD， between 2.3 V to 5.5 V. It contains a low power， high speed， 14-bit sampling ADC with no missing codes， an internal conversion clock， and a versatile serial interface port. The part also contains a low noise， wide bandwidth， short aperture delay track-and-hold circuit. On the CNV rising edge， it samples an analog input， IN+， between 0 V to VREF with respect to a ground sense， IN?。 The reference voltage， VREF， is applied externally and is set up to be the supply voltage. Its power scales linearly with the throughput. The SPI-compatible serial interface also features the ability， using the SDI input， to daisy-chain several ADCs on a single 3-wire bus and provides an optional busy indicator. It is compatible with 1.8 V， 2.5 V， 3 V， or 5 V logic using a separate supply （VIO）。 The AD7942 is housed in a 10-lead MSOP or a 10-lead LFCSP package yet fits in the same size footprint as the 8-lead MSOP or SOT-23. Operation for the AD7942 is specified from ?40°C to +85°C.