AD620AN Instrumentation Amplifiers Low Drift Low Power

The AD620AN is a precision, low-cost, low-power instrumentation amplifier manufactured by Analog Devices, the industry leader in high-performance analog ICs. Designed specifically for amplifying very small differential voltages in the presence of large common-mode signals, the AD620 has become one of the most widely used instrumentation amplifiers in both professional and educational electronics.

Unlike standard operational amplifiers, an instrumentation amplifier is optimized for high input impedance, high common-mode rejection, and extremely accurate differential gain — qualities that are essential when working with bridge sensors, thermocouples, strain gauges, biomedical electrodes, and other low-level signal sources.

The AD620AN allows the user to set the voltage gain anywhere from 1 V/V to 10,000 V/V using just a single external resistor (R_G), dramatically simplifying circuit design compared to multi-op-amp instrumentation amplifier topologies. This makes it equally well-suited for fixed-gain production circuits and adjustable laboratory measurement setups.

With a typical input offset voltage of just 125 µV, input bias current of only 2 nA, and a common-mode rejection ratio of 100 dB, the AD620 delivers exceptional DC accuracy and effectively rejects noise and interference from power-line hum, RF pickup, and ground loops — a critical capability when amplifying signals in the microvolt to millivolt range.

The IC operates from a wide supply range of ±2.3 V to ±18 V (or single-supply equivalent), and consumes only 1.3 mA of supply current, making it an excellent choice for battery-powered, portable, and remote sensing applications. The compact PDIP-8 through-hole package is breadboard-friendly and ideal for prototyping, lab work, and small-batch production.

Whether you're building a digital weighing scale, an ECG/EMG biomedical front-end, a precision strain gauge interface, or a multi-channel data acquisition system, the AD620AN provides the accuracy, low noise, and ease of use that make it the go-to choice for sensor signal conditioning.

Specifications

General

• Manufacturer: Analog Devices Inc.
• Part Number: AD620AN
• Product Category: Instrumentation Amplifier
• Amplifier Type: Differential Instrumentation Amplifier
• Number of Channels: 1
• Package / Case: PDIP-8 (through-hole)
• Mounting Style: Through Hole
• Packaging: Tube

Electrical Characteristics

• Gain Range: 1 V/V to 10,000 V/V (set by a single external resistor)
• Common Mode Rejection Ratio (CMRR): 100 dB
• Input Offset Voltage (V_OS): 125 µV (max)
• Input Bias Current (I_B): 2 nA
• Input Resistance (Max): 10 GΩ
• Supply Current (per Channel): 1.3 mA
• Power Dissipation (P_D): 650 mW
• Supply Voltage Range: ±2.3 V to ±18 V (dual supply) or equivalent single supply
• Bandwidth: 120 kHz (at gain = 100)

Environmental

• Operating Temperature Range: −40 °C to +85 °C
• Storage Temperature Range: −65 °C to +150 °C
• RoHS Compliance: No

Applications

• Load Cells and Digital Weighing Scales
• ECG and EMG Biomedical Instrumentation
• Strain Gauge Signal Conditioning
• Wheatstone Bridge Sensors (pressure, force, torque)
• Thermocouple Amplification
• Sensor Signal Conditioning for industrial transducers
• Data Acquisition Systems (DAQ)
• Industrial Automation and Process Control
• Portable and Battery-Powered Measurement Devices
• Multi-Channel Patient Monitoring Equipment
• Precision Laboratory Instruments
• Audio Differential Preamplifiers for low-level microphone signals
• High-Impedance Probe Buffers
• Educational Electronics and University Lab Experiments