Overview
The AD8421ARMZ, produced by Analog Devices Inc., is a low-cost, low-power, extremely low-noise, ultralow bias current, high-speed instrumentation amplifier. It is ideally suited for a broad spectrum of signal conditioning and data acquisition applications. This amplifier features extremely high common-mode rejection ratio (CMRR), allowing it to extract low-level signals in the presence of high-frequency common-mode noise over a wide temperature range.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Maximum Supply Current | 2.3 | mA |
| Input Voltage Noise at 1 kHz | 3.2 | nV/√Hz |
| Current Noise at 1 kHz | 200 | fA/√Hz |
| Bandwidth (G = 1) | 10 | MHz |
| Bandwidth (G = 100) | 2 | MHz |
| Settling Time to 0.001% (G = 10) | 0.6 | µs |
| CMRR at 20 kHz (G = 1) | 80 | dB |
| Slew Rate | 35 | V/µs |
| Input Offset Voltage Drift | 0.2 | µV/°C |
| Gain Drift (G = 1) | 1 | ppm/°C |
| Input Bias Current | 500 | pA |
| Supply Voltage Range | ±2.5 V to ±18 V (dual supply), 5 V to 36 V (single supply) | V |
| Operating Temperature Range | −40°C to +85°C (MSOP, SOIC), −40°C to +125°C (LFCSP) | °C |
Key Features
- Low power consumption with a maximum supply current of 2.3 mA.
- Extremely low noise with 3.2 nV/√Hz input voltage noise and 200 fA/√Hz current noise at 1 kHz.
- High-speed performance with a 10 MHz bandwidth at G = 1 and 2 MHz at G = 100.
- Fast settling time of 0.6 µs to 0.001% at G = 10.
- High CMRR of 80 dB at 20 kHz (G = 1) and up to 94 dB minimum.
- High precision DC performance with low input offset voltage drift (0.2 µV/°C) and low gain drift (1 ppm/°C).
- Robust input protection up to 40 V from the opposite supply rail.
- Gain settable with a single resistor from 1 to 10,000.
- Available in 8-lead LFCSP, MSOP, and SOIC packages.
Applications
- Medical instrumentation
- Precision data acquisition
- Microphone preamplification
- Vibration analysis
- Multiplexed input applications
- ADC driver
Q & A
- What is the maximum supply current of the AD8421?
The maximum supply current of the AD8421 is 2.3 mA.
- What is the input voltage noise of the AD8421 at 1 kHz?
The input voltage noise of the AD8421 at 1 kHz is 3.2 nV/√Hz.
- What is the bandwidth of the AD8421 at a gain of 1?
The bandwidth of the AD8421 at a gain of 1 is 10 MHz.
- How long does it take for the AD8421 to settle to 0.001% at a gain of 10?
The settling time to 0.001% at a gain of 10 is 0.6 µs.
- What is the CMRR of the AD8421 at 20 kHz and a gain of 1?
The CMRR of the AD8421 at 20 kHz and a gain of 1 is 80 dB.
- What is the slew rate of the AD8421?
The slew rate of the AD8421 is 35 V/µs.
- How is the gain of the AD8421 set?
The gain of the AD8421 is set with a single resistor and can range from 1 to 10,000.
- What are the available package types for the AD8421?
The AD8421 is available in 8-lead LFCSP, MSOP, and SOIC packages.
- What is the operating temperature range for the AD8421?
The operating temperature range for the AD8421 is −40°C to +85°C for MSOP and SOIC packages, and −40°C to +125°C for the LFCSP package.
- What are some typical applications of the AD8421?
Typical applications include medical instrumentation, precision data acquisition, microphone preamplification, vibration analysis, multiplexed input applications, and ADC drivers.
