The AD8421 is a low‑power, low‑noise instrumentation amplifier with 3 nV/√Hz voltage noise and 200 fA/√Hz current noise.
The AD8421 from Analog Devices is a high‑speed instrumentation amplifier designed for signal‑conditioning and data‑acquisition applications. It offers ultra‑low voltage noise of 3 nV/√Hz, low current noise of 200 fA/√Hz, and a wide bandwidth of up to 10 MHz at a gain of 1.
The device operates from dual supplies of ±2.5 V to ±18 V (or a single supply of 5 V to 36 V), provides a static current of about 2 mA, and supports gain settings from 1 to 10 000 via a single external resistor. Its high CMRR (up to 94 dB) and robust input protection make it suitable for precision measurement in noisy environments. This manual is written in Chinese.
| Input current noise (typical) | 200 fA/√Hz |
|---|---|
| Bandwidth (G = 1) | 10 MHz |
The gain can be set from 1 to 10 000 using a single external resistor.
The absolute maximum supply voltage is ±18 V.