The AD79801 is a 16-bit， successive approximation， analog-todigital converter （ADC） that operates from a single power supply， VDD. It contains a low power， high speed， 16-bit sampling ADC and a versatile serial interface port. On the CNV rising edge， it samples an analog input， IN+， between 0 V to REF with respect to a ground sense， IN?。 The reference voltage， REF， is applied externally and can be set independent of the supply voltage， VDD. Its power scales linearly with 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 the separate supply VIO. The AD7980 is housed in a 10-lead MSOP or a 10-lead LFCSP with operation specified from ?40°C to +125°C.