Overview
The AD8221AR-REEL7, produced by Analog Devices Inc., is a high-performance, gain-programmable instrumentation amplifier. It is renowned for delivering the industry’s highest Common Mode Rejection Ratio (CMRR) over frequency in its class. This amplifier maintains a minimum CMRR of 80 dB up to 10 kHz for all grades at a gain of 1, significantly reducing the need for additional filtering to reject wideband interference and line harmonics. The AD8221 is suitable for various applications requiring high precision and reliability, such as precision data acquisition, biomedical analysis, and aerospace instrumentation.
Key Specifications
| Parameter | Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Operating Range | VS | ±2.3 | ±18 | V | |
| Quiescent Current | T = −40°C to +85°C | 0.9 | 1 | 1.2 | mA |
| Small Signal −3 dB Bandwidth | G = 1 | 825 | kHz | ||
| Settling Time (0.01% of 10 V step) | G = 1 to 100 | 10 | µs | ||
| Output Swing | VS = ±2.3 V to ±5 V, RL = 10 kΩ | –VS + 1.1 | +VS − 1.2 | V | |
| Short-Circuit Current | 18 | mA | |||
| Input Bias Current | T = −40°C to +85°C | 0.5 | 2 | 3 | nA |
| Temperature Range for Specified Performance | −40 | +85 | °C |
Key Features
- High CMRR: Maintains a minimum CMRR of 80 dB up to 10 kHz for all grades at G = 1, reducing the need for additional filtering.
- Programmable Gain: Gain can be set from 1 to 1000 using a single external resistor.
- Wide Power Supply Range: Operates on power supplies ranging from ±2.3 V to ±18 V.
- High Bandwidth: Offers a small signal −3 dB bandwidth of 825 kHz at G = 1.
- Low Offset and Drift: Features low voltage offset, low offset drift, and low gain drift, making it ideal for applications requiring high DC performance.
- Compact Packaging: Available in 8-lead SOIC and MSOP packages, with the MSOP requiring half the board space of the SOIC.
- Temperature Range: Specified performance over the industrial temperature range of −40°C to +85°C and operational up to +125°C.
Applications
- Precision Data Acquisition: Ideal for high-precision data acquisition systems due to its high CMRR and low noise characteristics.
- Biomedical Analysis: Suitable for biomedical applications requiring high accuracy and reliability.
- Aerospace Instrumentation: Supports defense and aerospace applications, including those requiring the AQEC standard (AD8221-EP model).
- Weigh Scales and Industrial Process Controls: Used in weigh scales and industrial process control systems where high precision and reliability are crucial.
- Bridge Amplifiers: Excellent choice for bridge signal conditioning due to its high gain accuracy and low offset drift.
Q & A
- What is the typical bandwidth of the AD8221 at a gain of 1?
The AD8221 has a small signal −3 dB bandwidth of 825 kHz at a gain of 1.
- How is the gain of the AD8221 set?
The gain of the AD8221 can be set from 1 to 1000 using a single external resistor connected across the RG pins.
- What is the operating temperature range of the AD8221?
The AD8221 is specified to perform over the temperature range of −40°C to +85°C and is operational up to +125°C.
- What are the typical applications of the AD8221?
The AD8221 is used in precision data acquisition, biomedical analysis, aerospace instrumentation, weigh scales, industrial process controls, and bridge amplifiers.
- What is the CMRR of the AD8221 at 10 kHz?
The AD8221 maintains a minimum CMRR of 80 dB up to 10 kHz for all grades at G = 1.
- What are the available package types for the AD8221?
The AD8221 is available in 8-lead SOIC and 8-lead MSOP packages.
- What is the quiescent current of the AD8221?
The quiescent current of the AD8221 is typically 1 mA over the temperature range of −40°C to +85°C.
- What is the output swing of the AD8221?
The output swing of the AD8221 varies with the power supply voltage, but for VS = ±2.3 V to ±5 V, it is typically –VS + 1.1 V to +VS − 1.2 V.
- Is the AD8221 suitable for aerospace applications?
Yes, the AD8221 supports defense and aerospace applications, including those requiring the AQEC standard (AD8221-EP model).
- What is the short-circuit current of the AD8221?
The short-circuit current of the AD8221 is typically 18 mA.
