
Analog Devices
GENERAL DESCRIPTION
The AD7694 is a 16-bit, charge redistribution, successive approximation, PulSAR analog-to-digital converter (ADC) that operates from a single power supply, VDD, between 2.7 V to 5.25 V. It contains a low power, high speed, 16-bit sampling ADC with no missing codes (B grade), an internal conversion clock, and a serial, SPI-compatible 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 REF with respect to a ground sense, IN−. The reference voltage, REF, is applied externally and can be set up to the supply voltage.
FEATURES
16-bit resolution with no missing codes
Throughput: 250 kSPS at 5 V
INL: ±4 LSB max
S/(N + D): 92 dB at 20 kHz
THD: –106 dB at 20 kHz
Pseudo-differential analog input range:
0 V to VREF with VREF up to VDD
No pipeline delay
Single-supply operation: 2.7 V or 5 V
Proprietary serial interface
SPI®-/QSPI™-/MICROWIRE™-/DSP-compatible1
Supply Current: 540 μA at 2.7 V/100 kSPS,
800 μA at 5 V/100 kSPS
Standby current: 1 nA
8-lead MSOP package
Improved second source to LTC1864 and LTC1864L
APPLICATIONS
Battery-powered equipment
Data acquisition
Instrumentation
Medical instruments
Process control