Overview
The AD8638ARZ is a single, wide bandwidth, auto-zero operational amplifier produced by Analog Devices Inc. This amplifier is known for its high accuracy, low noise, and rail-to-rail output swing. It operates over a wide supply voltage range, from 5 V to 16 V single-supply or ±2.5 V to ±8 V dual-supply, making it versatile for various applications. The AD8638ARZ combines low cost with high performance, eliminating the need for external capacitors and reducing digital switching noise commonly found in chopper-stabilized amplifiers.
Key Specifications
| Parameter | Value | Conditions |
|---|---|---|
| Supply Voltage | 5 V to 16 V single-supply, ±2.5 V to ±8 V dual-supply | |
| Offset Voltage | 3 μV typical | |
| Offset Voltage Drift | 0.01 μV/°C to 0.04 μV/°C | −40°C ≤ TA ≤ +125°C |
| Input Bias Current | 40 pA maximum | |
| Supply Current | 1.3 mA maximum | |
| Bandwidth | 1.5 MHz typical | |
| Slew Rate | 2 V/μs typical | |
| Common Mode Rejection Ratio (CMRR) | 133 dB typical | −40°C ≤ TA ≤ +125°C |
| Power Supply Rejection Ratio (PSRR) | 143 dB typical | −40°C ≤ TA ≤ +125°C |
| Input Resistance | 22.5 TΩ | |
| Input Capacitance (Differential Mode) | 4 pF | |
| Input Capacitance (Common Mode) | 1.7 pF | |
| Output Voltage High | 4.97 V to 4.985 V | RL = 10 kΩ to VCM, −40°C ≤ TA ≤ +125°C |
| Package Type | 8-SOIC (0.154", 3.90mm Width) |
Key Features
- Auto-Zero Technology: Combines low cost with high accuracy and low noise, eliminating the need for external capacitors.
- Rail-to-Rail Output Swing: Operates over a wide supply voltage range, from 5 V to 16 V single-supply or ±2.5 V to ±8 V dual-supply.
- Low Offset and Drift: Typical offset voltage of 3 μV and drift of 0.01 μV/°C to 0.04 μV/°C.
- Low Input Bias Current: Maximum of 40 pA, ensuring minimal input current.
- Low Supply Current: Maximum of 1.3 mA, making it power-efficient.
- High CMRR and PSRR: Typical CMRR of 133 dB and PSRR of 143 dB, providing high rejection of common-mode and power supply noise.
- No Digital Switching Noise: Reduces noise found in most chopper-stabilized amplifiers.
Applications
- Pressure and Position Sensors: Ideal for applications requiring high accuracy and low noise.
- Strain Gage Amplifiers: Suitable for strain gage measurements due to its low drift and high accuracy.
- Medical Instrumentation: Used in medical equipment where precision and low noise are critical.
- Thermocouple Amplifiers: Applicable for thermocouple measurements with its low offset and drift.
- Automotive Sensors: Qualified for automotive applications, particularly for the AD8639 variant.
- Precision References and Current Sensing: Suitable for precision reference and current sensing applications due to its high accuracy and low noise.
Q & A
- What is the typical offset voltage of the AD8638ARZ?
The typical offset voltage of the AD8638ARZ is 3 μV.
- What is the operating supply voltage range for the AD8638ARZ?
The AD8638ARZ operates from 5 V to 16 V single-supply or ±2.5 V to ±8 V dual-supply.
- Does the AD8638ARZ require external capacitors?
No, the AD8638ARZ does not require external capacitors.
- What is the input bias current of the AD8638ARZ?
The maximum input bias current of the AD8638ARZ is 40 pA.
- What is the typical bandwidth of the AD8638ARZ?
The typical bandwidth of the AD8638ARZ is 1.5 MHz.
- What are the common applications of the AD8638ARZ?
The AD8638ARZ is commonly used in pressure and position sensors, strain gage amplifiers, medical instrumentation, thermocouple amplifiers, and automotive sensors.
- What is the package type of the AD8638ARZ?
The AD8638ARZ comes in an 8-SOIC (0.154", 3.90mm Width) package.
- What is the typical slew rate of the AD8638ARZ?
The typical slew rate of the AD8638ARZ is 2 V/μs.
- Does the AD8638ARZ have high CMRR and PSRR?
Yes, the AD8638ARZ has a typical CMRR of 133 dB and PSRR of 143 dB.
- Is the AD8638ARZ qualified for automotive applications?
The AD8639 variant is qualified for automotive applications, but the AD8638ARZ itself is not specifically mentioned as automotive-qualified.
