The AD7787 is a low-power, complete analog front end for low frequency measurement applications. It contains a low noise, high resolution 24-bit Σ-∆ ADC, and a single-channel, gain adjustable, with internal reference and VREF monitor function analog front end amplifier.
The AD7787 is a low‑power, 24‑bit sigma‑delta ADC designed for low‑frequency measurement applications. It features a differential and a single‑ended input, an internal clock, and programmable output rates from 9.5 Hz to 120 Hz. The device operates from a 2.5 V to 5.25 V supply and consumes as little as 75 pA in normal mode and 1 pA in power‑down mode.
Typical applications include smart transmitters, battery monitoring, portable instrumentation, temperature and pressure measurement, and weighing scales. The datasheet provides detailed specifications, timing characteristics, pin descriptions, grounding recommendations, and ordering information.
| Power Supply Voltage | 2.5 V to 5.25 V |
|---|---|
| Resolution | 19.5 Bits p‑p |
| RMS Noise (9.5 Hz) | 1.1 pV rms |
| Integral Nonlinearity | 3.5 ppm typical |
| Power‑down Current | 1 pA max |
| Bipolar Input Voltage Range | ±REFIN (typical ±2.5 V) |
The AD7787 operates from 2.5 V to 5.25 V.
The RMS noise is 1.1 pV at a 9.5 Hz update rate.
At 50 Hz and 60 Hz the AD7787 provides 65 dB min (73 dB typ) common‑mode rejection, with higher values for specific filter settings.