The AD7709 is a 16-bit Δ-Σ ADC chip with a programmable gain front end, simultaneous 50Hz and 60Hz rejection, VREF Select™ capability, and ISOURCE Select™ capability.
The AD7709 is a complete analog front‑end for low‑frequency measurement applications. It features a 16‑bit ADC, programmable gain front‑end, selectable reference inputs, three switchable excitation current sources, low‑side power switches, and a digital I/O port. The device operates from a single 3 V or 5 V supply and includes on‑chip functions such as rail‑to‑rail input buffers and a 32.768 kHz crystal‑driven PLL.
Typical applications include sensor, temperature, pressure, and weight‑scale measurements, as well as portable instrumentation. The part is supplied in a 24‑lead TSSOP package and supports multiple serial interfaces including SPI, QSPI, Microwire, and DSP‑compatible modes.
| Resolution | 16 bits |
|---|---|
| Power Consumption (IDD) | 1.5 mA max at 3 V |
| Input Range | ±2.56 V |
| Output Update Rate | 5.4 Hz min to 105 Hz max |
The AD7709 operates from –40 °C to +85 °C.
The AD7709 is housed in a 24‑lead TSSOP package.
The device supports 3‑wire serial SPI®, QSPI™, MICROWIRE™, and DSP compatible interfaces.