14-Bit, 250 kSPS PulSAR, Pseudo Differential ADC in MSOP/LFCSP

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.

APPLICATIONS

* Battery-powered equipment

* Data acquisition

* Instrumentation

* Medical instruments

* Process controls

* 14-bit resolution with no missing codes

* Throughput: 250 kSPS

* INL: ±0.4 LSB typical, ±1 LSB maximum (±0.0061% of FSR)

* SINAD: 85 dB @ 20 kHz