AD820ARZ - Single-Supply FET Op Amp | Analog Devices
MPN: AD820ARZ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.52 | $3.52 |
| 10 | $3.2 | $32.00 |
| 100 | $2.8 | $280.00 |
| 500 | $2.5 | $1,250.00 |
| 1,000 | $2.2 | $2,200.00 |
Drop-in alternatives for AD820ARZ — 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:
AD820BRZ
✅ Drop-In📋 Reference alternative (not in catalog)
AD820ARZ-REEL7
✅ Drop-In📋 Reference alternative (not in catalog)
AD820ARZ-REEL
✅ Drop-In📋 Reference alternative (not in catalog)
AD820ARZ Maximum Ratings & Electrical Characteristics
| Amplifier Type | J-FET |
| Number of Circuits | 1 |
| Output Type | Rail-to-Rail |
| Slew Rate | 3 V/µs |
| Gain Bandwidth Product | 1.9 MHz |
| Current - Input Bias | 2 pA |
| Voltage - Input Offset | 100 µV |
| Current - Supply | 700 µA |
| Current - Output / Channel | 25 mA |
| Voltage - Supply Span (Min) | 5 V |
| Voltage - Supply Span (Max) | 36 V |
| Operating Temperature | -40°C to +85°C |
| Package / Case | 8-SOIC (0.154", 3.90mm Width) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
AD820ARZ Pin Configuration
| Pin 1 | OFFSET NULL — Offset null adjustment |
| Pin 2 | IN- — Inverting input |
| Pin 3 | IN+ — Non-inverting input |
| Pin 4 | V- — Negative supply |
| Pin 5 | OFFSET NULL — Offset null adjustment |
| Pin 6 | OUT — Output |
| Pin 7 | V+ — Positive supply |
| Pin 8 | NC — No connection |
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
AD820ARZ is suitable for 6 applications: Battery-Powered Instrumentation, Portable Medical Devices, Sensor Signal Conditioning, Active Filters, Audio Signal Processing, Industrial Control Systems.
Battery-Powered Instrumentation
The AD820ARZ's low supply current of 700 µA and wide supply range (5 V to 36 V) make it ideal for battery-powered instruments. Its rail-to-rail output maximizes dynamic range, while the FET input ensures minimal loading on high-impedance sensors. In a typical pH meter, the AD820 buffers the high-impedance electrode signal, providing a low-impedance output for the ADC. The low bias current (2 pA) prevents electrode polarization, ensuring accurate readings over long battery life.
Recommended
Portable Medical Devices
In portable medical devices like glucose meters and pulse oximeters, the AD820ARZ provides precision signal conditioning with minimal power consumption. Its low input bias current (2 pA) is crucial for high-impedance biosensors, and the rail-to-rail output allows direct interfacing with ADCs. The wide supply range accommodates battery voltages from 5 V to 36 V, and the small SOIC-8 package saves board space. The device's low offset voltage (100 µV) ensures accurate measurement of small physiological signals.
Recommended
Sensor Signal Conditioning
The AD820ARZ is well-suited for conditioning signals from various sensors, including temperature, pressure, and strain gauges. Its FET input provides high input impedance, minimizing loading on sensors, and the low bias current reduces offset errors. The rail-to-rail output allows the signal to use the full ADC input range, improving resolution. In a bridge amplifier configuration, the AD820 can amplify the small differential voltage from a strain gauge, providing a clean, amplified signal for further processing.
Recommended
Active Filters
The AD820ARZ's 1.9 MHz gain bandwidth and 3 V/µs slew rate make it suitable for active filter designs in audio and instrumentation. Its low distortion and rail-to-rail output enable high-performance filters with wide dynamic range. In a second-order low-pass filter, the AD820 provides the necessary gain and phase response, while its low power consumption is beneficial in portable devices. The wide supply range allows operation from a variety of power sources.
Recommended
Audio Signal Processing
The AD820ARZ can be used in audio applications such as headphone amplifiers and preamplifiers. Its low noise and low distortion ensure high-fidelity audio reproduction, while the rail-to-rail output provides maximum headroom. The FET input offers high input impedance, making it compatible with high-impedance sources like electric guitars. In a headphone amplifier, the AD820 can drive low-impedance headphones with its 25 mA output current, providing clean audio amplification.
Recommended
Industrial Control Systems
In industrial control systems, the AD820ARZ provides reliable signal conditioning for process variables like temperature and pressure. Its wide supply range (up to 36 V) allows direct operation from industrial power rails, and its robust design ensures stable performance in harsh environments. The low bias current and offset voltage contribute to accurate control loops, while the rail-to-rail output interfaces directly with ADCs and microcontrollers. The device's small footprint is advantageous in space-constrained control modules.
Recommended
Recommended Products Summary
Engineering reference data for AD820ARZ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AD820BRZ | AD820ARZ-REEL7 | OPA2134PA |
|---|---|---|---|---|
| Package | 8-SOIC | 8-SOIC | 8-SOIC | 8-DIP |
| Brand | Analog Devices | Analog Devices | Analog Devices | Texas Instruments |
| Number of Circuits | 1 | 1 | 1 | 2 |
| Gain Bandwidth Product | 1.9 MHz | 1.9 MHz | 1.9 MHz | 8 MHz |
| Slew Rate | 3 V/µs | 3 V/µs | 3 V/µs | 20 V/µs |
| Input Bias Current | 2 pA | 2 pA | 2 pA | 5 pA |
| Supply Current | 700 µA | 700 µA | 700 µA | 4 mA |
| Supply Voltage Range | 5 V to 36 V | 5 V to 36 V | 5 V to 36 V | 5 V to 36 V |
Key Differentiators
- Lower supply current (vs OPA2134PA)
- Single-supply operation down to 5V (vs TL081CP)
- Rail-to-rail output (vs TL081CP)
Design Notes
Ensure proper power supply decoupling. Place a 0.1 µF ceramic capacitor close to each supply pin (V+ and V-) and a 10 µF tantalum capacitor for low-frequency decoupling. This is critical for maintaining stability and reducing noise in high-impedance circuits.
For best performance, use a ground plane and keep input traces short and shielded. The high input impedance of the FET input makes it susceptible to noise pickup, so route the input away from digital traces and power lines. Consider adding a guard ring around the input pins to minimize leakage currents.
Do not exceed the absolute maximum supply voltage of 36 V. Also, avoid driving capacitive loads greater than 100 pF without a series resistor, as this can cause oscillation. The AD820 is unity-gain stable, but large capacitive loads may require compensation.
Compliance Information
RoHS compliant per Analog Devices product page. Not AEC-Q100 qualified.