What is the function of Inverting amplifier?


Joined Apr 20, 2004
An inverting amplifier produces a 180 deg phase shift in the signal, making it a mirror image of the original.

Any amplifier requires negative feedback. Without it, the output swing caused by the input signal will tend to go as far as the supply rail will let it. The feedback lets the output be proportioned to the input, so the gain will be predictible.

Wikipedia has an articles and references about negative feedback - http://en.wikipedia.org/wiki/Negative_feedback.


Joined Apr 27, 2007
Why have to produce a 180 degrees out of phase with the input signal? What is the usage?
One example of use is on bridged amplifiers, where there are two amplifiers 180º out of phase supplying the signal to a common speaker. Both outputs are connected to the speaker that way. The purpose of this is to have twice the gain of each amplifier and the output power doubled, keeping the supply voltage low.