0 Comparator IC Tutorial

Comparator symbol

This page will show you basic ideas regarding comparators, and its operation and simple applications.
Comparator is an electronic  device that compares two voltages or current and feed in its input terminals and reflect this comparison to its output. Common comparator ICs are LM339,LM393. These comparators are commonly used in simple voltage detector projects and simple analog to digital converter circuits.

comparator response to input signals

Comparator operation
When the non-inverting input (marked +) is  higher compared to inverting input (marked -) the output of the comparator is high, and when the non-inverting input  is lower compared to inverting input (marked -) the output is low.
The IC picture below is the internal connection of 339 quad comparator ic.Pin 3 is the Vcc and pin 12 is usually a ground pin or negative voltage source. This IC is usually used for simple voltage detector circuitry.

LM339 pins and internal circuitry