LM324 Quad OP-AMP IC

LM324 Op-Amp Pin Configuration

LM324 Quad Op-Amp IC Features and Specifications

• Integrated with four Op-Amps in a single package
• Wide power supply Range

1. Singe supply – 3V to 32V
2. Dual supply – ±1.5V to ±16V

• Low Supply current – 700uA
• Single supply for four op-amp operation enables reliable operation
• Operating ambient temperature – 0˚C to 70˚C
• Soldering pin temperature – 260 ˚C (for 10 seconds – prescribed)

LM324 Equivalent Quad Op-Amp ICs

LM3900, LMC660, LM339, LT014, LM2900, LM324A, LM324E, LM324-N, LM324W

Brief Description

LM324 is a Quad op-amp IC integrated with four op-amps powered by a common power supply. The differential input voltage range can be equal to that of power supply voltage. The default input offset voltage is very low which is of magnitude 2mV. The operating temperature ranges from 0˚C to 70˚C at ambient whereas the maximum junction temperature can be upto 150˚C. Generally, op-amps can perform mathematical operations.

LM324 Explanation with Example

Consider, an motor running with a variable load. As the load increases the current increases which in turn increases the temperature of the motor. So, our job is to shut down the system if the temperature increases beyond rated. This is the place where op amp operates as a positive comparator. Check out Difference between Op-Amp and Comparator. Here a thermistor does the job whose resistance varies with temperature.

Below will be a simple circuit connection to sense temperature and control a system.

At Temperature = 25˚C, RT=10kὨ. Inv Input=1.32V and Non-Inv Input=2.36V.

Thus, Output is HIGH and it can drive a motor ON through a transistor or relay.

At Temperature = above 70˚C, RT=3kὨ. Inv Input=1.32V and Non-Inv Input=1.06V.

Thus, Output is LOW and it can drive a motor OFF through a transistor or relay.

If the temperature is to be monitored at three or four positions of the motor then LM324 can be used in below configuration. An orientation example for two temperature sensing RT1 and RT2,

Supply connection:

Single Supply Connection

Dual Supply Connection

Above is the supply configuration for both single and dual supply connections.

Applications:

• Transducer Amplifiers
• Filter circuits, Voltage followers
• Integrator, Differentiator, Summer, adder, Voltage follower, etc.,
• DC gain blocks
• Comparators (Loop control & regulation)

2D-model