GENERAL DESCRIPTION

The AD7194 is a low noise, complete analog front end for high precision measurement applications. It contains a low noise, 24-bit sigma-delta (Σ-Δ) analog-to-digital converter (ADC). The on-chip low noise gain stage means that signals of small amplitude can interface directly to the ADC.

FEATURES

Fast settling filter option

8 differential/16 pseudo differential input channels

RMS noise: 11 nV at 4.7 Hz (gain = 128)

15.5 noise-free bits at 2.4 kHz (gain = 128)

Up to 22 noise-free bits (gain = 1)

Offset drift: ±5 nV/°C

Gain drift: ±1 ppm/°C

Programmable gain (1 to 128)

Output data rate: 4.7 Hz to 4.8 kHz

Internal or external clock

Simultaneous 50 Hz/60 Hz rejection

4 general-purpose digital outputs

Power supply

   AVDD: 3 V to 5.25 V

   DVDD: 2.7 V to 5.25 V

Current: 4.65 mA

Temperature range: −40°C to +105°C

Package: 32-lead LFCSP

Interface

   3-wire serial

   SPI, QSPI™, MICROWIRE™, and DSP compatible

   Schmitt trigger on SCLK

APPLICATIONS

PLC/DCS analog input modules

Data acquisition

Strain gage transducers