AD8655ARZ - Low Noise Precision CMOS Op Amp | Analog Devices
MPN: AD8655ARZ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.94 | $2.94 |
| 10 | $2.65 | $26.50 |
| 100 | $2.36 | $236.00 |
| 500 | $2.12 | $1,060.00 |
| 1,000 | $1.91 | $1,910.00 |
Drop-in alternatives for AD8655ARZ — 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-REEL
✅ Drop-In📋 Reference alternative (not in catalog)
AD8656ARZ
⚡ Same Package✓ In Stock
$1.82 / Unit
View Datasheet →AD8626ARZ
✅ Drop-In📋 Reference alternative (not in catalog)
OPA2134UA/2K5
✅ Drop-In✓ In Stock
$2.1 / Unit
View Datasheet →AD8605ARZ-REEL7
✅ Drop-In✓ In Stock
$0.78 / Unit
View Datasheet →AD8655ARZ Maximum Ratings & Electrical Characteristics
| Amplifier Type | General Purpose |
| Number of Circuits | 1 |
| Output Type | Rail-to-Rail |
| Slew Rate | 11 V/µs |
| Gain Bandwidth Product | 28 MHz |
| Current - Input Bias | 1 pA |
| Voltage - Input Offset | 250 µV max |
| Current - Supply | 4.5 mA |
| Current - Output / Channel | 220 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 |
| Mounting Type | Surface Mount |
| Noise Density | 2.7 nV/√Hz at 10 kHz |
| THD+N | 0.0007% |
AD8655ARZ Pin Configuration
| Pin 1 | OUT — Amplifier output |
| Pin 2 | -IN — Inverting input |
| Pin 3 | +IN — Non-inverting input |
| Pin 4 | V- — Negative supply |
| Pin 5 | NC — No connect |
| Pin 6 | NC — No connect |
| 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
AD8655ARZ is suitable for 6 applications: Precision Sensor Signal Conditioning, Portable Medical Devices, Audio Preamplifiers, Active Filters, Battery-Powered Instrumentation, Photodiode Amplifier.
Precision Sensor Signal Conditioning
The AD8655ARZ's low offset voltage (250 µV max) and low noise (2.7 nV/√Hz) make it ideal for amplifying small signals from sensors such as thermocouples, strain gauges, and photodiodes. Its rail-to-rail input and output allow direct interfacing with ADCs and microcontrollers. The CMOS input provides high impedance, minimizing loading on the sensor. For best performance, use a low-pass filter at the output to reduce high-frequency noise. The amplifier's 28 MHz bandwidth ensures fast response for dynamic measurements.
Recommended
Portable Medical Devices
The AD8655ARZ operates from 2.7 V to 5.5 V, making it suitable for battery-powered medical devices like glucose monitors and pulse oximeters. Its low power consumption (4.5 mA) extends battery life. The low noise and high precision ensure accurate measurement of physiological signals. The rail-to-rail output allows direct connection to low-voltage ADCs. For safety, ensure proper isolation and ESD protection in the design. The small 8-SOIC package saves board space in compact devices.
Recommended
Audio Preamplifiers
With a THD+N of 0.0007% and low noise, the AD8655ARZ is excellent for audio preamplifiers and headphone amplifiers. It provides high fidelity signal amplification with minimal distortion. The rail-to-rail output maximizes dynamic range, and the 28 MHz bandwidth ensures accurate reproduction of high-frequency audio. For optimal performance, use high-quality passive components and proper grounding. The amplifier can drive headphones directly with its 220 mA output current capability.
Recommended
Active Filters
The AD8655ARZ's 28 MHz gain-bandwidth product makes it suitable for active filters in communication and instrumentation systems. It can implement low-pass, high-pass, and band-pass filters with high accuracy. The low noise ensures minimal signal degradation. The rail-to-rail output allows wide dynamic range. For filter design, use precision resistors and capacitors to achieve desired cutoff frequencies. The amplifier's stability with capacitive loads up to 100 pF simplifies filter implementation.
Recommended
Battery-Powered Instrumentation
The AD8655ARZ's low supply voltage (2.7 V to 5.5 V) and moderate supply current (4.5 mA) make it ideal for battery-powered instruments like multimeters and data loggers. Its precision and low noise ensure accurate measurements. The rail-to-rail input and output allow full-scale signal handling. For extended battery life, consider powering down the amplifier when not in use. The 8-SOIC package is compact and suitable for portable designs.
Recommended
Photodiode Amplifier
The AD8655ARZ's low input bias current (1 pA) and low noise make it ideal for transimpedance amplifiers used with photodiodes. It can convert small photocurrents into usable voltage signals with high accuracy. The CMOS input minimizes leakage current, preserving signal integrity. The 28 MHz bandwidth supports high-speed optical communication. For stability, place a feedback capacitor in parallel with the feedback resistor to compensate for input capacitance. The rail-to-rail output allows direct interface with ADCs.
Recommended
Recommended Products Summary
Engineering reference data for AD8655ARZ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AD8655ARZ-REEL | AD8656ARZ | AD8626ARZ | OPA2134UA | AD8605ARZ-REEL7 |
|---|---|---|---|---|---|---|
| Package | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Texas Instruments | Analog Devices |
| Number of Channels | 1 | 1 | 2 | 2 | 2 | 1 |
| Gain Bandwidth Product | 28 MHz | 28 MHz | 28 MHz | 5 MHz | 8 MHz | 10 MHz |
| Slew Rate | 11 V/µs | 11 V/µs | 11 V/µs | 2.5 V/µs | 20 V/µs | 5 V/µs |
| Voltage Noise Density | 2.7 nV/√Hz | 2.7 nV/√Hz | 2.7 nV/√Hz | 12 nV/√Hz | 8 nV/√Hz | 7 nV/√Hz |
| Input Offset Voltage (max) | 250 µV | 250 µV | 250 µV | 350 µV | 500 µV | 250 µV |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | ±2.5 V to ±18 V | 2.7 V to 5.5 V |
Key Differentiators
- Lowest noise in its class (vs AD8626ARZ)
- Higher bandwidth (vs AD8605ARZ-REEL7)
- Lower THD+N (vs OPA2134UA)
Design Notes
The AD8655ARZ operates from 2.7 V to 5.5 V. Use a clean power supply with adequate decoupling. Place a 0.1 µF ceramic capacitor close to the V+ and V- pins to filter high-frequency noise. For best performance, use a low-ESR tantalum or ceramic capacitor of 10 µF in parallel for bulk decoupling.
For optimal noise performance, keep the input traces short and shielded. Use a ground plane to minimize noise pickup. Place the feedback resistor and capacitor close to the inverting input to reduce parasitic capacitance. Avoid routing high-speed digital traces near the input pins.
Do not exceed the absolute maximum supply voltage of 6 V. Ensure the input common-mode voltage stays within the specified range to avoid output phase reversal. The output can drive capacitive loads up to 100 pF; for larger loads, add a series resistor to maintain stability.
Compliance Information
RoHS compliant per Analog Devices product page. Not AEC-Q100 qualified.
