The AD7981 is a 16-bit, successive approximation, PulSAR®analog-to-digital converter (ADC) designed for high temperature operation. The AD7981 is capable of sample rates of up to 600 kSPS while maintaining low power consumption from a single power supply, VDD. It is a fast throughput, high accuracy, high temperature, successive approximation register (SAR) ADC, packaged in a small form factor with a versatile serial port interface (SPI).On the CNV rising edge, the AD7981 samples an analog input, IN+, between 0 V and 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. The device 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.For space constrained applications, the AD7981 is available in a 10-lead mini small outline package (MSOP) with operation speci-fied from −55°C to +175°C and 10-lead ceramic flat package (FLATPACK) with operation specified from −55°C to +210°C. These packages are designed for robustness at extreme temperatures, including monometallic wire bonding, and are qualified for up to 1000 hours of operation at the maximum temperature rating.The AD7981 is a member of a growing series of high temperature qualified products offered by Analog Devices, Inc. For a complete selection of available high temperature products, see the high temperature product list and qualification data available at www.analog.com/hightemp.ApplicationsOil and gas explorationAvionicsHeavy industrialHigh temperature environmentsScientific instrumentation