US 11,057,700 B1
Microphone device, telephone device, and decoupling circuit
Hsin-Chun Lee, New Taipei (TW); I-Ming Chen, New Taipei (TW); and Chang-Yi Hsueh, New Taipei (TW)
Assigned to Wistron Corporation, New Taipei (TW)
Filed by Wistron Corporation, New Taipei (TW)
Filed on Feb. 7, 2020, as Appl. No. 16/784,246.
Claims priority of application No. 108146159 (TW), filed on Dec. 17, 2019.
Int. Cl. H04R 3/00 (2006.01); H03F 3/00 (2006.01); H04R 19/04 (2006.01)
CPC H04R 3/00 (2013.01) [H03F 3/005 (2013.01); H04R 19/04 (2013.01); H04R 2499/11 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A decoupling circuit, comprising:
a first capacitor, wherein a first terminal of the first capacitor is coupled to a first terminal of an audio source;
a first resistor, wherein a first terminal of the first resistor is coupled to a second terminal of the first capacitor, and a second terminal of the first resistor is coupled to a second terminal of the audio source; and
a switch, wherein a first terminal of the switch is coupled to the second terminal of the first capacitor and the first terminal of the first resistor, and a second terminal of the switch is coupled to the second terminal of the audio source,
wherein the first capacitor and the first resistor are configured to absorb noise generated by the switch during switching,
wherein when the audio source is a differential input, the decoupling circuit further comprises:
a second capacitor, wherein a first terminal of the second capacitor is coupled to one of the first terminal and the second terminal of the audio source, and a second terminal of the second capacitor is coupled to a first output terminal;
a second resistor, wherein a first terminal of the second resistor is coupled to a bias voltage, and a second terminal of the second resistor is coupled to the one of the first terminal and the second terminal of the audio source;
a third capacitor, wherein a first terminal of the third capacitor is coupled to the other one of the first terminal and the second terminal of the audio source, and a second terminal of the third capacitor is coupled to a second output terminal; and
a third resistor, wherein a first terminal of the third resistor is coupled to a reference voltage terminal, and a second terminal of the third resistor is coupled to the other one of the first terminal and the second terminal of the audio source and the first terminal of the third capacitor.