The AD8421 is a low cost, low power, extremely low noise, ultra-low bias current, high speed instrumentation amplifier which is ideally suited for a broad spectrum of signal conditioning and data acquisition applications. This breakthrough product features the highest CMRR available, allowing it to extract low-level signals in the presence of high-frequency common mode noise over a wide temperature range.
The 10 MHz bandwidth, 35 V/µs slew rate, and 0.7 µs settling time to 0.01% (G = 1) allow the AD8421 to amplify high-speed signals and excel in applications that require high channel-count multiplexed systems. Even at high gain, the current feedback architecture preserves this performance, for example, at G = 100, the bandwidth is 2 MHz and the settling time is 0.6 µs. The AD8421 has excellent distortion performance, allowing use in demanding applications such as vibration analysis.
The AD8421 delivers industry-leading 3 nV/√Hz input voltage noise and 200 fA/√Hz current noise with only 2 mA quiescent current, making it an ideal choice for measuring low-level signals. For applications with significant source impedance, the AD8421 employs novel process technology and innovative design techniques to provide groundbreaking noise performance limited only by the sensor.
The AD8421 uses a unique input protection method to give it robust inputs while still maintaining very low noise. This input protection allows voltages 40 V from the opposite supply rail without damage.
A single resistor sets gains between 1 and 10,000. The reference pin can be used to apply a precise offset to the output voltage.
The AD8421 performance is specified from −40°C to +85°C and has typical performance curves to 125°C. It is available in MSOP and SOIC packages.
Features and Benefits
| AmplifiersSPICE Models |
| Document | note |
| AD8421: 3 nV/√Hz, Low Power Instrumentation Amplifier Data Sheet (Rev. 0) | PDF 335 kB |
| AD8421-EP: Enhanced Product Data Sheet (Rev. 0) | PDF 493.63 K |
| AD8421-DSCC: Military Data Sheet |
| Document | note |
| AN-1264: Precision Signal Conditioning for High Resolution Industrial Applications (Rev. 0) | PDF 469 kB |
| Document | note |
| Part Number | Package | Packing Qty | Temp Range | Price 100-499 | Price 1000+ | RoHS |
|---|---|---|---|---|---|---|
| AD8237ARMZ Production | 8 ld MSOP | OTH 50 | -40 to 125C | 1.16 | 0.93 | Y |
| AD8237ARMZ-R7 Production | 8 ld MSOP | REEL 1000 | -40 to 125C | 0 | 0.93 | Y |
| AD8237ARMZ-RL Production | 8 ld MSOP | REEL 3000 | -40 to 125C | 0 | 0.93 | Y |
| Part Number | Description | Price | RoHS |
|---|---|---|---|
| EVAL-INAMP-ICF-RMZ | Evaluation Board for AD8420 and 8237 | 34.58 | Y |
