Overview
The AD8421BRZ, manufactured by Analog Devices Inc., is a low-cost, low-power, extremely low-noise, ultra-low bias current, high-speed instrumentation amplifier. It is designed for a broad spectrum of signal conditioning and data acquisition applications. The AD8421 is known for its high precision DC performance, excellent AC specifications, and robust input protection, making it suitable for various demanding applications.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Bandwidth (G = 1) | 10 | MHz |
| Bandwidth (G = 100) | 2 | MHz |
| Settling Time to 0.001% (G = 10) | 0.6 | µs |
| CMRR (G = 1) at 20 kHz | 80 | dB |
| CMRR (G = 1) Minimum | 94 | 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 |
| Input Voltage Noise at 1 kHz | 3.2 | nV/√Hz |
| Current Noise at 1 kHz | 200 | fA/√Hz |
| Maximum Supply Current | 2.3 | mA |
| Operating Temperature Range | −40°C to +85°C (MSOP, SOIC), −40°C to +125°C (LFCSP) | °C |
| Package Types | 8-lead LFCSP, 8-lead MSOP, 8-lead SOIC |
Key Features
- High precision DC performance with 94 dB CMRR minimum (G = 1) and 0.2 µV/°C maximum input offset voltage drift.
- Low noise: 3.2 nV/√Hz input voltage noise and 200 fA/√Hz current noise at 1 kHz.
- High speed: 10 MHz bandwidth (G = 1), 2 MHz bandwidth (G = 100), and 0.6 µs settling time to 0.001% (G = 10).
- Robust input protection: inputs protected to 40 V from opposite supply rail.
- Flexible gain setting: gain set with a single resistor (G = 1 to 10,000).
- Low power consumption: maximum supply current of 2.3 mA.
- Wide supply voltage range: ±2.5 V to ±18 V (dual supply), 5 V to 36 V (single supply).
Applications
- Medical instrumentation
- Precision data acquisition
- Microphone preamplification
- Vibration analysis
- Multiplexed input applications
- ADC driver
Q & A
- 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.
- What is the settling time of the AD8421 to 0.001% at a gain of 10?
The settling time of the AD8421 to 0.001% at a gain of 10 is 0.6 µs.
- 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 maximum input bias current of the AD8421?
The maximum input bias current of the AD8421 is 500 pA.
- What are the available package types for the AD8421?
The AD8421 is available in 8-lead LFCSP, 8-lead MSOP, and 8-lead SOIC packages.
- What is the operating temperature range for the AD8421 in different packages?
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 LFCSP packages.
- What are some typical applications of the AD8421?
The AD8421 is typically used in medical instrumentation, precision data acquisition, microphone preamplification, vibration analysis, multiplexed input applications, and as an ADC driver).
- How is the gain of the AD8421 set?
The gain of the AD8421 is set with a single resistor, allowing gains from 1 to 10,000).
- What is the slew rate of the AD8421?
The slew rate of the AD8421 is 35 V/µs).
- What is the maximum supply current of the AD8421?
The maximum supply current of the AD8421 is 2.3 mA).
