LM321G, manufactured by UTC (Unisonic Technologies, Taiwan), is a single-channel low-power general-purpose operational amplifier

1. Core Function

Core application: Amplify weak signals, signal conditioning, voltage comparison and buffer driving; a cost-effective & low-power signal-processing amplifier.

Key Electrical Parameters

• Channel: Single operational amplifier

• Supply Voltage: 3V~32V single supply, suitable for battery and industrial applications

• Quiescent Current: Ultra-low power consumption, 430μA @ 5V

• Gain Bandwidth Product: 1MHz, optimized for low-frequency signals

• Package: SOT-23-5 (3×1.6mm), compact outline

• Operating Temperature: -40℃ ~ +85℃, industrial grade

2. Main Features

• Sensor signal amplification: Boost millivolt-level weak signals from temperature, pressure, photo and Hall sensors to readable voltage range for MCU.

• Voltage follower / Buffer: Impedance matching, circuit isolation between preceding and post-stage; drive ADC and light loads.

• Active filtering: Low-pass / high-pass / band-pass filtering to eliminate noise for audio and sensor signals.

• Voltage comparison: Threshold detection, overvoltage/undervoltage alarm and logic level judgment.

• Low-power driving: Constant-current LED drive, small-load control and signal conditioning for battery-operated equipment.

3. Application Fields

Consumer Electronics

• Smart bands & watches: Sensor signal conditioning and low-noise amplification

• Bluetooth & Wi-Fi modules: RF buffer and noise filtering

• Small home appliances: Temperature control, battery level detection and key level identification

• Headsets & speakers: Audio pre-amplification and volume regulation

Industrial & IoT

• Sensor nodes: Amplification for temperature, humidity, pressure and vibration signals

• Battery-powered devices: Low-power signal processing and voltage monitoring

• Instruments & meters: Meter driver, signal calibration and small-signal amplification

• Smart home: Door/window contact sensor, human motion & ambient light detection

Power & Charging Products

• Battery chargers: Current/voltage sampling amplification and overcurrent protection

• Power supply modules: Feedback amplification, reference voltage buffering and load current monitoring

4. Summary Slogan (for customer & social media)

LM321G from UTC in SOT-23-5 package is a low-power single op-amp with wide 3V~32V supply range and industrial temperature rating. It is widely used for sensor amplification, signal buffering, voltage comparison and low-power driving in consumer electronics, IoT, industrial control and power supply products.