GENERAL DESCRIPTION
The AD7794/AD7795 are low power, low noise, complete analog front ends for high precision measurement applications. They contain a low noise, 24-/16-bit ∑-Δ ADC with six differential inputs. The on-chip low noise instrumentation amplifier means that signals of small amplitude can be interfaced directly to the ADC.

FEATURES
   Up to 23 effective bits
   RMS noise: 40 nV @ 4.17 Hz, 85 nV @ 16.7 Hz
   Current: 400 μA typical
   Power-down: 1 μA maximum
   Low noise, programmable gain, instrumentation amp
   Band gap reference with 4 ppm/°C drift typical
   Update rate: 4.17 Hz to 470 Hz
   Six differential analog inputs
   Internal clock oscillator
   Simultaneous 50 Hz/60 Hz rejection
   Reference detect
   Programmable current sources
   On-chip bias voltage generator
   Burnout currents
   Low-side power switch
   Power supply: 2.7 V to 5.25 V
   Temperature range:
      B grade: –40°C to +105°C
      C grade: –40°C to +125°C
   Independent interface power supply
   24-lead TSSOP
   3-wire serial interface
      SPI®, QSPI™, MICROWIRE™, and DSP compatible
      Schmitt trigger on SCLK

APPLICATIONS
   Temperature measurement
   Pressure measurement
   Weigh scales
   Strain gage transducers
   Gas analysis