AD8656ARZ - Dual 3nV Precision CMOS Op Amp | Analog Devices
MPN: AD8656ARZ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.56 | $25.60 |
| 100 | $2.28 | $228.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.82 | $1,820.00 |
Drop-in alternatives for AD8656ARZ — 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:
AD8655ARZ
✅ Drop-In✓ In Stock
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View Datasheet →OPA2134UA/2K5
✅ Drop-In✓ In Stock
$2.1 / Unit
View Datasheet →LM4562MA/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
AD8620ARZ
✅ Drop-In✓ In Stock
$8.5 / Unit
View Datasheet →ADA4610-2ARZ
✅ Drop-In✓ In Stock
$2.19 / Unit
View Datasheet →AD8656ARZ Maximum Ratings & Electrical Characteristics
| Number of Channels | 2 |
| Supply Voltage Range | 2.7 V to 5.5 V |
| Input Offset Voltage (max) | 250 µV over VCM |
| Voltage Noise Density | 2.7 nV/√Hz at 10 kHz |
| THD+N | 0.0007% |
| Gain-Bandwidth Product | 28 MHz |
| Slew Rate | 11 V/µs |
| Input Type | Rail-to-Rail |
| Output Type | Rail-to-Rail |
| Operating Temperature Range | -40°C to +125°C |
| Package | 8-SOIC |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Amplifier Type | CMOS |
| Technology | DigiTrim |
AD8656ARZ Pin Configuration
| Pin 1 | OUT A — Output of amplifier A |
| Pin 2 | -IN A — Inverting input of amplifier A |
| Pin 3 | +IN A — Non-inverting input of amplifier A |
| Pin 4 | V- — Negative supply voltage |
| Pin 5 | +IN B — Non-inverting input of amplifier B |
| Pin 6 | -IN B — Inverting input of amplifier B |
| Pin 7 | OUT B — Output of amplifier B |
| Pin 8 | V+ — Positive supply voltage |
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
AD8656ARZ is suitable for 6 applications: Precision Sensor Signal Conditioning, ADC Driver, Active Filters, Audio Processing, Medical Instrumentation, Battery-Powered Devices.
Precision Sensor Signal Conditioning
The AD8656ARZ's low input offset voltage (250 µV max) and low noise (2.7 nV/√Hz) make it ideal for amplifying small sensor signals, such as those from thermocouples or strain gauges. Its rail-to-rail output allows full-scale signal swing, maximizing dynamic range in single-supply systems. The dual-channel configuration enables simultaneous conditioning of multiple sensors, reducing component count and board space. The high CMRR and PSRR reject common-mode noise and power supply variations, ensuring accurate measurements in industrial environments.
Recommended
ADC Driver
The AD8656ARZ is well-suited for driving high-resolution ADCs, such as the AD7172-2, due to its low noise and low distortion. Its rail-to-rail output can swing close to the ADC's full-scale input range, maximizing the signal-to-noise ratio. The fast slew rate (11 V/µs) ensures accurate settling for high-speed sampling. The dual-channel configuration allows driving two ADC inputs or implementing a differential driver with a single IC. The low output impedance ensures stable driving of the ADC's sampling capacitor.
Recommended
Active Filters
The AD8656ARZ's 28 MHz gain-bandwidth product and low noise make it suitable for active filter designs, such as low-pass or band-pass filters in communication systems. Its rail-to-rail input and output allow wide dynamic range, and the low distortion (0.0007% THD+N) preserves signal integrity. The dual-channel configuration enables implementing a second-order filter with a single IC, saving space. The high slew rate ensures minimal distortion for large signal swings.
Recommended
Audio Processing
The AD8656ARZ's low noise (2.7 nV/√Hz) and low THD+N (0.0007%) make it an excellent choice for high-fidelity audio applications, such as headphone amplifiers or audio mixers. Its rail-to-rail output can drive headphones directly without additional circuitry. The dual-channel configuration is ideal for stereo audio paths. The wide supply voltage range (2.7 V to 5.5 V) allows operation from a single lithium-ion battery, making it suitable for portable audio devices.
Recommended
Medical Instrumentation
The AD8656ARZ's precision and low noise are critical for medical devices such as ECG or EEG amplifiers, where signal integrity is paramount. Its low offset voltage (250 µV max) ensures accurate biopotential measurements, and the rail-to-rail output allows interfacing with ADCs. The dual-channel configuration can be used for multi-lead measurements. The industrial temperature range (-40°C to +125°C) ensures reliable operation in clinical environments.
Recommended
Battery-Powered Devices
The AD8656ARZ's low supply voltage (2.7 V) and low quiescent current make it suitable for battery-powered devices, such as portable sensors or wearables. Its rail-to-rail input and output maximize signal swing with limited supply headroom. The low noise ensures accurate signal processing even with weak sensor outputs. The dual-channel configuration reduces component count, saving board space and power. The device is available in a small 8-SOIC package, ideal for compact designs.
Recommended
Recommended Products Summary
Engineering reference data for AD8656ARZ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AD8656ARMZ | AD8655ARZ | OPA2134UA/2K5 | LM4562MA/NOPB | AD8620ARZ | ADA4610-2ARZ |
|---|---|---|---|---|---|---|---|
| Package | 8-SOIC | 8-MSOP | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC |
| Brand | Analog Devices | Analog Devices | Analog Devices | Texas Instruments | Texas Instruments | Analog Devices | Analog Devices |
| Number of Channels | 2 | 2 | 1 | 2 | 2 | 2 | 2 |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | ±2.5 V to ±18 V | ±2.5 V to ±17 V | ±5 V to ±13 V | ±5 V to ±15 V |
| Input Offset Voltage (max) | 250 µV | 250 µV | 250 µV | 500 µV | 100 µV | 100 µV | 400 µV |
| Voltage Noise Density | 2.7 nV/√Hz | 2.7 nV/√Hz | 2.7 nV/√Hz | 8 nV/√Hz | 2.7 nV/√Hz | 6 nV/√Hz | 7.3 nV/√Hz |
| Gain-Bandwidth Product | 28 MHz | 28 MHz | 28 MHz | 8 MHz | 55 MHz | 25 MHz | 16.3 MHz |
| Slew Rate | 11 V/µs | 11 V/µs | 11 V/µs | 20 V/µs | 20 V/µs | 25 V/µs | 16 V/µs |
Key Differentiators
- Lowest noise in its class (vs OPA2134UA/2K5)
- DigiTrim technology for low offset (vs LM4562MA/NOPB)
- Rail-to-rail input and output (vs AD8620ARZ)
Design Notes
Ensure proper power supply decoupling by placing 0.1 µF and 10 µF capacitors as close as possible to the V+ and V- pins. This minimizes high-frequency noise and ensures stable operation. For single-supply applications, connect V- to ground and use a single 2.7 V to 5.5 V supply.
For optimal noise performance, use a ground plane and keep input traces short and shielded. Avoid routing high-frequency digital signals near the input pins. Use surface-mount components to minimize parasitic inductance and capacitance.
Do not exceed the absolute maximum supply voltage of 6 V, as this can damage the device. Also, ensure the input common-mode voltage stays within the specified range to avoid phase reversal. For ADC driving applications, consider adding a small series resistor (e.g., 10 Ω) to isolate the amplifier output from the ADC's sampling capacitor.
Compliance Information
RoHS compliant per Analog Devices product page. No AEC-Q100 qualification indicated for this part.
