GENERAL DESCRIPTION
The AD7781 is a complete, low power front-end solution for bridge sensor products, including weigh scales, strain gages, and pressure sensors. It contains a precision, low power, 20-bit sigma-delta (Σ-Δ) ADC, an on-chip, low noise programmable gain amplifier (PGA), and an on-chip oscillator.

FEATURES
   Pin-programmable filter response
      Update rate: 10 Hz or 16.7 Hz
   Pin-programmable in-amp gain
   Pin-programmable power-down and reset
   Status function
   Internal clock oscillator
   Internal bridge power-down switch
   Current
      115 μA typical (gain = 1)
      330 μA typical (gain = 128)
   Simultaneous 50 Hz/60 Hz rejection
   Power supply: 2.7 V to 5.25 V
   −40°C to +105°C temperature range
   Independent interface power supply
   Packages
      14-lead, narrow body SOIC
      16-lead TSSOP
   2-wire serial interface (read-only device)
      SPI compatible
      Schmitt trigger on SCLK

APPLICATIONS
   Weigh scales
   Pressure measurement
   Industrial process control
   Portable instrumentation