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