ADI AD7942BRMZ

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 0V 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.

• 14-bit resolution with no missing codes
• Throughput: 250 kSPS
• INL: ±0.4 LSB typical, ±η LSB maximum (±0.0061% of FSR)
• SINAD: 85 dB at 20 kHz
• THD: −100 dB at 20 kHz
• Pseudo differential analog input range 0 V to VREF with VREF up to VDD
• No pipeline delay
• Single-supply 2.3 V to 5.5 V operation with 1.8 V/2.5 V/3 V/5 V logic interface
• Proprietary serial interface SPI-/QSPI-/MICROWIRE-/DSP-compatible
• Daisy-chaining for multiple ADCs and busy indicator
• Power dissipation 1.25 mW at 2.5 V/100 kSPS, 3.6 mW at 5 V/100 kSPS, 1.25 μW at 2.5 V/100 SPS
• Standby current: 1 nA
• 10-lead package: MSOP and 3 mm × 3 mm LFCSP
• Pin-for-pin compatible with the 16-bit AD7685

• Battery-powered equipment
• Data acquisition
• Instrumentation
• Medical instruments
• Process controls