Overview
The AD8628ARZ, manufactured by Analog Devices Inc., is a zero-drift, single-supply, rail-to-rail input/output operational amplifier. This device is part of the AD8628/AD8629/AD8630 family, known for its ultralow offset, drift, and bias current. It combines high accuracy and low noise, making it suitable for a wide range of precision applications. The AD8628ARZ operates on a single supply from 2.7 V to 5 V and is fully specified over this range, offering benefits previously found only in more expensive auto-zeroing or chopper-stabilized amplifiers.
Key Specifications
| Parameter | Symbol | Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|---|
| Offset Voltage | VOS | −40°C ≤ TA ≤ +125°C | 1 | 5 | 10 | µV |
| Input Offset Drift | ∆VOS/∆T | −40°C ≤ TA ≤ +125°C | 0.002 | 0.02 | µV/°C | |
| Input Bias Current | IB | −40°C ≤ TA ≤ +125°C | 30 | 100 | 300 | pA |
| Common-Mode Rejection Ratio | CMRR | VCM = 0 V to 5 V | 120 | 130 | 140 | dB |
| Large Signal Voltage Gain | AVO | RL = 10 kΩ, VO = 0.3 V to 4.7 V | 125 | 140 | 145 | dB |
| Supply Current | IS | −40°C ≤ TA ≤ +125°C | 0.85 | 1.0 | 1.2 | mA |
| Slew Rate | SR | RL = 10 kΩ | 1.0 | V/µs | ||
| Gain Bandwidth Product | GBP | 2.5 | MHz | |||
| Voltage Noise Density | en | f = 1 kHz | 22 | nV/√Hz |
Key Features
- Lowest Auto-Zero Amplifier Noise: The AD8628ARZ features extremely low noise, with a voltage noise density of 22 nV/√Hz at 1 kHz and a peak-to-peak noise of 0.5 µV (0.1 Hz to 10 Hz).
- Low Offset Voltage and Drift: It has an offset voltage of only 1 µV and an input offset drift of less than 0.005 µV/°C, ensuring high accuracy over a wide temperature range.
- Rail-to-Rail Input and Output Swing: The amplifier supports rail-to-rail input and output swing, which simplifies input biasing and maximizes signal-to-noise ratio (SNR).
- High Gain, CMRR, and PSRR: The AD8628ARZ offers high gain, common-mode rejection ratio (CMRR), and power supply rejection ratio (PSRR) of up to 130 dB.
- Low Input Bias Current: It has a very low input bias current of 100 pA maximum, which is beneficial for high-impedance sources.
- Low Supply Current: The device operates with a low supply current of 1.0 mA, making it power-efficient.
- No External Components Required: The amplifier does not require any external capacitors, simplifying the design process.
Applications
- Automotive Sensors: Qualified for automotive applications, the AD8628ARZ is suitable for various automotive sensor systems.
- Pressure and Position Sensors: Its high precision and low drift make it ideal for pressure and position sensors.
- Strain Gage Amplifiers: The amplifier is used in strain gage applications where high accuracy and low noise are critical.
- Medical Instrumentation: It is used in medical equipment due to its high precision and reliability.
- Thermocouple Amplifiers: The AD8628ARZ is suitable for thermocouple applications requiring high accuracy and low noise.
- Precision Current Sensing and Photodiode Amplifiers: Its low noise and high precision make it suitable for precision current sensing and photodiode amplification.
Q & A
- What is the typical offset voltage of the AD8628ARZ?
The typical offset voltage of the AD8628ARZ is 1 µV.
- What is the input offset drift of the AD8628ARZ?
The input offset drift is less than 0.005 µV/°C.
- What is the common-mode rejection ratio (CMRR) of the AD8628ARZ?
The CMRR is up to 130 dB.
- What is the maximum input bias current of the AD8628ARZ?
The maximum input bias current is 100 pA.
- Does the AD8628ARZ require any external components?
No, the AD8628ARZ does not require any external components.
- What is the operating temperature range of the AD8628ARZ?
The operating temperature range is from −40°C to +125°C.
- What are some typical applications of the AD8628ARZ?
Typical applications include automotive sensors, pressure and position sensors, strain gage amplifiers, medical instrumentation, thermocouple amplifiers, and precision current sensing and photodiode amplifiers.
- What is the slew rate of the AD8628ARZ?
The slew rate is 1.0 V/µs.
- What is the gain bandwidth product (GBP) of the AD8628ARZ?
The GBP is 2.5 MHz.
- What is the voltage noise density of the AD8628ARZ at 1 kHz?
The voltage noise density at 1 kHz is 22 nV/√Hz.
