A Comparator is a circuit which accepts two voltages or currents and then switches the output showing which is bigger. Comparators are found in components like analogue to digital converters. Comparators are like operational amplifiers except a comparator is designed to operate with positive feedback and output saturated at one power rail or the other.
How a Comparator works
A comparator samples two input pins and turns on the output when identifying a difference or similarity.
An example is when you have a minus voltage on the inverting Pin and a plus non-inverting. When the voltage on the non-inverting equals the inverting voltage the Pin turns on. Normally the output Pin is open and switches to ground when the comparator is activated.
Why use a Comparator?
The primary use of a comparator is converting analogue to digital (ADC). Two supply voltages are applied and the difference determines a high or low digital signal.
Types of Comparator
Current sense
Differential / Dual differential
Dual / Dual CMOS
Dual voltage / General voltage
General-purpose
Ground sense
High speed / high-speed CMOS
Low current CMOS
Low power / low voltage / low-power CMOS
Micropower
Nano power
Precision
Push/pull output
Quad differential
Rail to rail
Voltage
Window
Mounting Types
Surface mount
Through-hole
Comparator power supply types
Dual
Single
Various package types, pins, sizes, channels per chip, PSRR (power supply rejection ratio), CMRR (common-mode rejection ratio) are all available.
