what is dc offset exactly and how is it applied to electronic circuits?

 

what is dc offset exactly and how is it applied to electronic circuits?

DC offset is a deliberate introduction of a DC level to a circuit to shift its operating point.

For example, DC offset is applied to transistors to make them work correctly, as well as op-amps for use with a single polarity power supply.

There are countless other examples, but those are common ones.

 

DC offset might be a bad thing sometimes. When wiring an Operational Amplifier, a DC voltage will appear at its output even no voltage difference is applied at its input.

There are ways to counter that, though.

 

DC offset occurs when hardware,for example, such as a sound card, adds DC current to a recorded audio signal. This current results in a recorded waveform that is not centred around the baseline .

In some cases, when DC-Offset is present, glitches and other unexpected results can occur when sound effects are applied to the audio file. You can compensate for this DC offset by adding a constant value to the samples in the sound file.