AD8628ARZ - Zero-Drift Op Amp, Rail-to-Rail | Analog Devices
MPN: AD8628ARZ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.49 | $1.49 |
| 10 | $1.35 | $13.50 |
| 100 | $1.2 | $120.00 |
| 500 | $1.1 | $550.00 |
| 1,000 | $1 | $1,000.00 |
Drop-in alternatives for AD8628ARZ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
AD8629ARZ
✅ Drop-In✓ In Stock
$1.55 / Unit
View Datasheet →AD8630ARZ
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AD8628WARZ-R7
✅ Drop-In📋 Reference alternative (not in catalog)
OPA2188AIDR
✅ Drop-In📋 Reference alternative (not in catalog)
MCP6V11-E/SN
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2050CS8
✅ Drop-In📋 Reference alternative (not in catalog)
AD8628ARZ Maximum Ratings & Electrical Characteristics
| Amplifier Type | Zero-Drift (Auto-Zero) |
| Number of Circuits | 1 |
| Output Type | Rail-to-Rail |
| Slew Rate | 1 V/µs |
| Gain Bandwidth Product | 2.5 MHz |
| Current - Input Bias | 100 pA (max) |
| Voltage - Input Offset | 1 µV |
| Current - Supply | 1.7 mA |
| Current - Output / Channel | 30 mA |
| Voltage - Supply Span (Min) | 2.7 V |
| Voltage - Supply Span (Max) | 5.5 V |
| Operating Temperature | -40°C to +125°C |
| Package / Case | 8-SOIC (0.154", 3.90mm Width) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
AD8628ARZ Pin Configuration
| Pin 1 | OUT — Amplifier output |
| Pin 2 | -IN — Inverting input |
| Pin 3 | +IN — Non-inverting input |
| Pin 4 | V- — Negative supply (ground in single-supply) |
| Pin 5 | NC — No connect |
| Pin 6 | NC — No connect |
| Pin 7 | NC — No connect |
| Pin 8 | V+ — Positive supply |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
AD8628ARZ is suitable for 6 applications: Precision Instrumentation, Medical Instrumentation, Sensor Signal Conditioning, Battery-Powered Devices, Data Acquisition Systems, Automotive Electronics.
Precision Instrumentation
The AD8628ARZ's ultralow offset voltage (1 µV) and drift (0.002 µV/°C) make it ideal for precision instrumentation amplifiers, data acquisition systems, and bridge transducers. Its rail-to-rail input/output allows full-scale signal processing in single-supply systems, while the low bias current (100 pA) minimizes errors in high-impedance sensors. The auto-zero architecture ensures long-term stability, reducing the need for calibration. In a typical bridge amplifier circuit, the AD8628ARZ provides accurate amplification of small differential signals with minimal offset error, enabling high-resolution measurements.
Recommended
Medical Instrumentation
In medical devices such as patient monitors and diagnostic equipment, the AD8628ARZ provides the precision and low noise required for biosignal amplification. Its low offset drift ensures accurate measurements over temperature, and the rail-to-rail output allows direct interfacing with ADCs. The low supply current (1.7 mA) is suitable for battery-powered portable medical devices. For ECG or EEG front-ends, the AD8628ARZ can be used in instrumentation amplifier configurations to reject common-mode noise and amplify small biopotentials with high accuracy.
Recommended
Sensor Signal Conditioning
The AD8628ARZ is well-suited for conditioning signals from thermocouples, RTDs, strain gauges, and photodiodes. Its low input bias current (100 pA) minimizes loading on high-impedance sensors, while the low offset voltage and drift ensure accurate conversion of small sensor outputs. The wide supply range (2.7 V to 5.5 V) allows operation in both 3.3 V and 5 V systems. In a thermocouple amplifier, the AD8628ARZ can provide high gain with low offset error, enabling precise temperature measurement. The auto-zero feature eliminates drift over time, reducing maintenance in industrial settings.
Recommended
Battery-Powered Devices
For portable and battery-powered equipment, the AD8628ARZ offers a balance of low power consumption (1.7 mA) and high precision. Its rail-to-rail input/output maximizes dynamic range in low-voltage systems, and the 2.7 V minimum supply voltage allows operation from a single lithium-ion cell. The low offset voltage reduces errors in battery monitoring circuits, and the small SOIC-8 package saves board space. In a battery management system, the AD8628ARZ can amplify shunt resistor voltages for current sensing with high accuracy, enabling precise state-of-charge estimation.
Recommended
Data Acquisition Systems
The AD8628ARZ is an excellent choice for driving high-resolution ADCs in data acquisition systems. Its low output impedance and rail-to-rail output can drive the sampling capacitor of SAR ADCs without significant settling errors. The low noise (19.4 nV/√Hz) and high PSRR (130 dB) ensure that power supply noise does not corrupt the signal. In a multi-channel DAQ, the AD8628ARZ can be used as a buffer or gain stage before the ADC, providing accurate signal conditioning. The auto-zero feature maintains accuracy over temperature and time, which is critical for long-term monitoring applications.
Recommended
Automotive Electronics
In automotive applications, the AD8628ARZ's wide temperature range (-40°C to +125°C) and high reliability make it suitable for sensor interfaces, battery monitoring, and motor control. The low offset drift ensures accurate measurements over the automotive temperature range, and the rail-to-rail output allows direct interfacing with microcontrollers. The device is available in an automotive-grade version (AD8628WARZ-R7) for stricter requirements. In a battery management system for electric vehicles, the AD8628ARZ can amplify cell voltage measurements with high precision, contributing to accurate state-of-charge and health monitoring.
Recommended
Recommended Products Summary
Engineering reference data for AD8628ARZ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AD8629ARZ | AD8630ARZ | OPA2188AIDR | MCP6V11-E/SN | LTC2050CS8 |
|---|---|---|---|---|---|---|
| Package | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC |
| Brand | Analog Devices | Analog Devices | Analog Devices | Texas Instruments | Microchip Technology | Analog Devices |
| Number of Circuits | 1 | 2 | 4 | 2 | 1 | 1 |
| Offset Voltage (max) | 1 µV | 1 µV | 1 µV | 25 µV | 2 µV | 0.5 µV |
| Input Bias Current (max) | 100 pA | 100 pA | 100 pA | 150 pA | 1 pA | 20 pA |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 4 V to 36 V | 2.2 V to 5.5 V | 2.7 V to 11 V |
| Gain Bandwidth Product | 2.5 MHz | 2.5 MHz | 2.5 MHz | 2 MHz | 2 MHz | 3 MHz |
| Quiescent Current | 1.7 mA | 1.7 mA | 1.7 mA | 0.45 mA | 0.45 mA | 0.75 mA |
Key Differentiators
- Ultralow offset voltage of 1 µV (vs OPA2188AIDR)
- Very low input bias current of 100 pA (vs MCP6V11-E/SN)
- Wide supply voltage range of 2.7 V to 5.5 V (vs LTC2050CS8)
Design Notes
The AD8628ARZ operates from a 2.7 V to 5.5 V single supply. For best performance, use a clean, low-noise supply and place a 0.1 µF ceramic capacitor close to the V+ pin (pin 8) and a 10 µF tantalum capacitor at the supply entry point. The device draws 1.7 mA quiescent current, so power dissipation is minimal, but ensure the supply voltage does not exceed the absolute maximum rating of 6 V to avoid damage.
For optimal performance, place the AD8628ARZ on a PCB with a solid ground plane. Keep the input traces short and shielded to minimize noise pickup. Use a 0.1 µF decoupling capacitor as close as possible to the V+ pin (pin 8) and a 10 µF bulk capacitor nearby. For high-impedance sensor inputs, consider a guard ring around the input pins to reduce leakage currents.
The auto-zero clock can generate high-frequency noise at the output. In sensitive applications, add a low-pass filter at the output to remove this noise. Also, ensure the input common-mode voltage stays within the specified range (including both rails) to avoid phase reversal. The output can swing close to the rails, but not exactly to them, so account for the output saturation voltage in your design.
Compliance Information
RoHS compliant per Analog Devices product page. Not AEC-Q100 qualified for standard version; automotive grade available as AD8628WARZ-R7.