AD8675ARZ - 36V Precision, 2.8nV/√Hz Rail-to-Rail Op Amp | Analog Devices
MPN: AD8675ARZ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.15 | $4.15 |
| 10 | $3.72 | $37.20 |
| 100 | $3.1 | $310.00 |
| 500 | $2.6 | $1,300.00 |
| 1,000 | $2.2 | $2,200.00 |
Drop-in alternatives for AD8675ARZ — 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:
AD8627ARZ
✅ Drop-In✓ In Stock
$2.82 / Unit
View Datasheet →OPA2134UA/2K5
✅ Drop-In✓ In Stock
$2.1 / Unit
View Datasheet →AD8620ARZ
✅ Drop-In✓ In Stock
$8.5 / Unit
View Datasheet →OP177GSZ
✅ Drop-In✓ In Stock
$2.19 / Unit
View Datasheet →AD8675ARZ Maximum Ratings & Electrical Characteristics
| Amplifier Type | General Purpose |
| Number of Circuits | 1 |
| Output Type | Rail-to-Rail |
| Slew Rate | 2.5 V/µs |
| Gain Bandwidth Product | 10 MHz |
| Current - Input Bias | 2 nA (max) |
| Voltage - Input Offset | 10 µV (max) |
| Current - Supply | 2.7 mA |
| Current - Output / Channel | 20 mA |
| Voltage - Supply Span (Min) | 10 V |
| Voltage - Supply Span (Max) | 36 V |
| Operating Temperature | -40°C to +125°C |
| Package / Case | 8-SOIC (0.154", 3.90mm Width) |
| Mounting Type | Surface Mount |
| Voltage Noise Density | 2.8 nV/√Hz at 1 kHz |
| Open-Loop Gain | 120 dB |
| Common Mode Rejection Ratio | 120 dB |
AD8675ARZ Pin Configuration
| Pin 1 | NULL — Offset null |
| Pin 2 | -IN — Inverting input |
| Pin 3 | +IN — Non-inverting input |
| Pin 4 | V- — Negative supply |
| Pin 5 | NULL — Offset null |
| Pin 6 | OUT — Output |
| Pin 7 | V+ — Positive supply |
| Pin 8 | NC — No connect |
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
AD8675ARZ is suitable for 6 applications: Precision Instrumentation, PLL Filters, Sensor Amplifiers, Audio Processing, Medical Instrumentation, Active Filters.
Precision Instrumentation
The AD8675ARZ's ultralow offset (10 µV) and low noise (2.8 nV/√Hz) make it ideal for precision instrumentation amplifiers, data acquisition front-ends, and sensor signal conditioning. Its wide supply range (10V-36V) accommodates industrial sensors and transducers, while the rail-to-rail output maximizes dynamic range. The low input bias current (2 nA) minimizes errors when interfacing with high-impedance sources like pH probes and photodiodes. In a typical bridge amplifier circuit, the AD8675 provides accurate amplification with minimal drift over temperature, ensuring reliable measurements in laboratory and field environments.
Recommended
PLL Filters
The AD8675ARZ is well-suited for active loop filters in phase-locked loops (PLLs) due to its wide bandwidth (10 MHz) and low noise. In a PLL, the op amp filters the charge pump output to control the VCO tuning voltage. The low offset voltage ensures accurate frequency locking, while the rail-to-rail output allows the VCO to be tuned across its full range. The high open-loop gain (120 dB) maintains filter accuracy, and the low bias current reduces leakage in the integrator. For a 100 kHz loop bandwidth, the AD8675 provides stable filtering with minimal phase noise contribution, making it ideal for RF synthesizers and clock recovery circuits.
Recommended
Sensor Amplifiers
The AD8675ARZ excels in sensor amplification applications, including thermocouple, strain gauge, and pressure sensor interfaces. Its low offset voltage (10 µV) and low drift ensure accurate measurement of small sensor signals, while the low noise (2.8 nV/√Hz) preserves signal integrity. The wide supply range allows direct operation from 24V industrial rails, and the rail-to-rail output simplifies interfacing with ADCs. In a typical thermocouple amplifier, the AD8675 provides a gain of 100 with minimal error, and its low bias current prevents loading of the thermocouple. The extended temperature range (-40°C to +125°C) makes it suitable for industrial and automotive environments.
Recommended
Audio Processing
The AD8675ARZ is an excellent choice for high-end audio applications, including DAC output buffers, active crossovers, and headphone amplifiers. Its low voltage noise (2.8 nV/√Hz) ensures a low noise floor, while the wide bandwidth (10 MHz) preserves audio fidelity. The rail-to-rail output allows maximum signal swing, and the low distortion (THD+N) makes it suitable for audiophile-grade equipment. In a DAC output stage, the AD8675 provides a clean, buffered signal with minimal coloration. Its low offset voltage prevents DC offset at the output, protecting speakers. The device's small SOIC package enables compact audio designs.
Recommended
Medical Instrumentation
The AD8675ARZ is suitable for medical instrumentation such as ECG, EEG, and patient monitoring systems. Its low noise (2.8 nV/√Hz) and low offset (10 µV) are critical for detecting small biopotential signals. The high common-mode rejection ratio (120 dB) rejects interference from power lines and muscle artifacts. The low input bias current (2 nA) minimizes loading of high-impedance electrodes. The wide supply range allows operation from battery or isolated supplies, and the extended temperature range ensures reliability in clinical environments. In an ECG front-end, the AD8675 provides clean amplification of the QRS complex, enabling accurate heart rate monitoring.
Recommended
Active Filters
The AD8675ARZ is ideal for active filter designs, including low-pass, high-pass, and band-pass filters in signal conditioning chains. Its wide bandwidth (10 MHz) supports high-frequency filters, while the low noise and low offset ensure accurate filtering. The rail-to-rail output allows maximum signal swing, and the high open-loop gain (120 dB) maintains filter accuracy. In a 4th-order Butterworth low-pass filter with a cutoff of 100 kHz, the AD8675 provides a flat passband and sharp roll-off. The device's low bias current reduces errors in high-impedance filter networks, and its small package enables compact filter designs for portable instruments.
Recommended
Recommended Products Summary
Engineering reference data for AD8675ARZ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AD8675ARMZ | AD8627ARZ | OPA2134UA | AD8620ARZ | OP177GSZ |
|---|---|---|---|---|---|---|
| Package | 8-SOIC | 8-MSOP | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC |
| Brand | Analog Devices | Analog Devices | Analog Devices | Texas Instruments | Analog Devices | Analog Devices |
| Number of Circuits | 1 | 1 | 1 | 2 | 2 | 1 |
| Gain Bandwidth Product | 10 MHz | 10 MHz | 5 MHz | 8 MHz | 5 MHz | 0.6 MHz |
| Voltage Noise Density | 2.8 nV/√Hz | 2.8 nV/√Hz | 6 nV/√Hz | 8 nV/√Hz | 6 nV/√Hz | 10 nV/√Hz |
| Input Offset Voltage (max) | 10 µV | 10 µV | 50 µV | 500 µV | 50 µV | 10 µV |
| Input Bias Current (max) | 2 nA | 2 nA | 1 pA | 5 pA | 1 pA | 2 nA |
| Supply Voltage Range | 10V to 36V | 10V to 36V | 5V to 26V | 5V to 36V | 5V to 26V | 6V to 36V |
Key Differentiators
- Ultralow voltage noise of 2.8 nV/√Hz (vs OPA2134UA)
- Ultralow offset voltage of 10 µV (vs OPA2134UA)
- Single-channel precision with rail-to-rail output (vs AD8620ARZ)
Design Notes
For optimal performance, use 0.1 µF ceramic capacitors close to the V+ and V- pins to decouple high-frequency noise. Additionally, a 10 µF tantalum capacitor in parallel can help stabilize the supply under transient loads. The AD8675 operates from 10V to 36V single supply or ±5V to ±18V dual supply; ensure the supply voltage does not exceed the absolute maximum ratings.
To minimize noise pickup, keep the input traces short and shielded. Use a ground plane under the op amp and avoid routing high-speed digital traces near the input pins. For best DC performance, use a guard ring around the input pins to reduce leakage currents, especially in high-impedance applications.
Do not exceed the absolute maximum supply voltage of 36V. The output can swing close to the rails, but avoid driving loads that require more than 20 mA output current. When driving capacitive loads greater than 500 pF, add a series resistor to prevent oscillation. Also, ensure the input common-mode voltage stays within the specified range to avoid phase reversal.
Compliance Information
RoHS compliant per Analog Devices product page. Not AEC-Q100 qualified.
