Common mode noise cancellation circuit for unbalanced signals

摘要

This invention provides a common mode noise cancellation circuit for the unbalanced signals. The unbalanced signals come from a signal source with a first signal terminal and a second signal terminal having a first grounding potential. The common mode noise cancellation circuit comprises a grounding terminal and a subtractor. The grounding terminal with a second grounding potential is electrically coupled to the second signal terminal of the signal source through an impedance unit. The subtractor comprises a first receiving terminal, a second receiving terminal and a signal output terminal. The first receiving terminal and the second receiving terminal are electrically coupled to the first signal terminal and the second signal terminal respectively for receiving the unbalanced signals. The subtractor subtracts the noise coming from the first receiving terminal and the noise coming from the second receiving terminal to reduce the output noise of the signal output terminal.

主权项

1. A common mode noise cancellation circuit for the unbalanced signals, the unbalanced signals coming from a first signal terminal and a second signal terminal of a signal source, the second signal terminal having a first grounding potential, the common mode noise cancellation circuit comprising:
a grounding terminal, having a second grounding potential, the grounding terminal is electrically coupled to the second signal terminal of the signal source via an impedance unit; and a subtractor, comprising a first receiving terminal, a second receiving terminal and a signal output terminal, the first receiving terminal and the second receiving terminal are electrically coupled to the first signal terminal and the second signal terminal respectively, for receiving the unbalanced signals, the subtractor subtracting noise coming from the first signal terminal and noise coming from the second signal terminal from each other for reducing noise outputted by the signal output terminal.