Analog Devices AD7799 Product Info

• RMS noise:
  27 nV at 4.17 Hz (AD7799)
  65 nV at 16.7 Hz (AD7799)
  40 nV at 4.17 Hz (AD7798)
  85 nV at 16.7 Hz (AD7798)
• Current: 380 μA typical
• Power-down: 1 μA maximum
• Low noise, programmable gain, instrumentation amp
• Update rate: 4.17 Hz to 470 Hz 3 differential inputs
• Internal clock oscillator
• Simultaneous 50 Hz/60 Hz rejection
• Reference detect
• Low-side power switch
• Programmable digital outputs
• Burnout currents
• Power supply: 2.7 V to 5.25 V

The AD7798/AD7799 are low power, low noise, complete analog front ends for high precision measurement applications. The AD7798/AD7799 contains a low noise, 16-/24-bit Σ-Δ ADC with three differential analog inputs. The on-chip, low noise instrumentation amplifier means that signals of small amplitude can be interfaced directly to the ADC. With a gain setting of 64, the rms noise is 27 nV for the AD7799 and 40 nV for the AD7798 when the update rate equals 4.17 Hz.

On-chip features include a low-side power switch, reference detect, programmable digital output pins, burnout currents, and an internal clock oscillator. The output data rate from the part is software-programmable and can be varied from 4.17 Hz to 470 Hz.

The part operates with a power supply from 2.7 V to 5.25 V. The AD7798 consumes a current of 300 μA typical, whereas the AD7799 consumes 380 μA typical. Both devices are housed in a 16-lead TSSOP package.

Applications

• Weigh scales
• Pressure measurement
• Strain gauge transducers
• Gas analysis
• Industrial process control
• Instrumentation
• Portable instrumentation
• Blood analysis
• Smart transmitters
• Liquid/gas chromotography 6-digit DVM