
Analog Devices
GENERAL DESCRIPTION
The AD7176-2 is a fast settling, highly accurate, high resolution, multiplexed Σ-Δ analog-to-digital converter (ADC) for low bandwidth input signals. Its inputs can be configured as two fully differential or four pseudo differential inputs via the integrated crosspoint multiplexer. An integrated precision, 2.5 V, low drift (2 ppm/°C), band gap internal reference (with an output reference buffer) adds functionality and reduces the external component count.
FEATURES
Fast and flexible output rate—5 SPS to 250 kSPS
Fast settling time—20 µs
Channel scan data rate of 50 kSPS/channel
Performance specifications
17 noise free bits at 250 kSPS
20 noise free bits at 2.5 kSPS
22 noise free bits at 5 SPS
INL ±2.5 ppm of FSR
85 dB rejection of 50 Hz and 60 Hz with 50 ms settling
User-configurable input channels
2 fully differential or 4 pseudo differential
Crosspoint multiplexer
On-chip 2.5 V reference (drift 2 ppm/°C)
Internal oscillator, external crystal, or external clock
Power supply
Single supply: 5 V AVDD1, 2 V to 5 V AVDD2 and IOVDD
Optional split supply: AVDD1 and AVSS ± 2.5 V
Current: 7.8 mA
Temperature range: −40°C to +105°C
3- or 4-wire serial digital interface (Schmitt trigger on SCLK)
CRC error checking
SPI, QSPI, MICROWIRE, and DSP compatible
APPLICATIONS
Process control: PLC/DCS modules
Temperature and pressure measurement
Medical and scientific multichannel instrumentation
Chromatography