ADI Unveils AD5940: Integrated Potentiostat & Impedance Front End for Next‑Gen Bio‑Chemical Sensors

Analog Devices has launched the AD5940, a single‑chip front‑end that merges potentiostat and electrochemical impedance spectroscopy (EIS) functions into one ultra‑low‑power package. The solution is engineered for next‑generation wearable health monitors and intelligent electrochemical sensors.

Unlike conventional discrete assemblies that require multiple ICs and introduce size and accuracy constraints, the AD5940 delivers a 16‑bit, 800 kSPS SAR ADC with an integrated anti‑alias filter, programmable gain amplifier, and ±1.35 V input range. Its dual‑loop potentiostat—one low‑bandwidth loop that generates AC signals up to 200 Hz and one high‑bandwidth loop that reaches 200 kHz—operates at only 6.5 µA in biased mode.

The chip supports 2‑, 3‑ and 4‑lead electrochemical sensors, enabling time‑domain amperometric, voltammetric, or frequency‑domain impedance measurements on a single board. Built‑in diagnostics monitor supply voltage, die temperature, and reference stability, giving developers confidence in long‑term reliability.

Designed for “always‑on” wearables, the AD5940’s autonomous sequencer and 6 kB SRAM allow users to program complex measurement routines via SPI or to let the chip run pre‑defined command sequences without continuous host intervention. FIFO buffers and interrupt flags keep data flow smooth, while the integrated ADC and front‑end can be paired with the AD8233 AFE to form a complete biopotential/impedance system.

Applications span industrial gas detection, liquid analytics, material characterization, vital‑sign monitoring, impedance spectroscopy, and disease management—any scenario where precision bio‑chemical sensing is critical.