AD7156 is a 1.8V, 3mm × 3mm, 2-channel capacitance converter with ultralow power consumption, fast response time, suitable for buttons and switches, proximity sensing, contactless switching, position detection, etc. Level detection and portable products.
The AD7156 from Analog Devices is a 2‑channel capacitance‑to‑digital converter designed for ultralow‑power applications. It operates from 1.8 V to 3.6 V, consumes as little as 70 pA typical supply current, and provides fast 10 ms conversion per channel with a 0.3 ms wake‑up time. The device includes adaptive environmental compensation, a programmable CAPDAC, and a 2‑wire I²C‑compatible serial interface.
Typical applications include button sensing, proximity detection, contactless switching, position and level detection, and other portable product interfaces. The part is supplied in a 10‑lead LFCSP package (3 mm × 3 mm × 0.8 mm) and is rated for operation from –40 °C to +85 °C.
| Supply voltage range | 1.8 V to 3.6 V |
|---|---|
| Operating temperature range | –40 °C to +85 °C |
| Power‑down current | 2 µA typical |
| Conversion time per channel | 10 ms |
| Sensor capacitance range | 0 pF to 13 pF |
| Sensitivity | up to 3 fF |
| CAPDAC full range | 10‑12.5 pF |
| Resolution | > 2.0 fF |
The AD7156 operates from 1.8 V to 3.6 V.
The device provides two capacitance input channels.
Each channel converts in 10 ms.
It uses a 2‑wire I²C‑compatible serial interface (SCL and SDA).