The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 09, 2014
Filed:
Mar. 27, 2012
Bin-song MA, Shenzhen, CN;
Yong-song Shi, Shenzhen, CN;
Bin-Song Ma, Shenzhen, CN;
Yong-Song Shi, Shenzhen, CN;
Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd., Shenzhen, CN;
Hon Hai Precision Industry Co., Ltd., New Taipei, TW;
Abstract
An earphone jack drive circuit applied in an electronic device is provided. The earphone jack drive circuit includes a mute circuit; a micro-controller including a detect pin and a control pin; a delay switch circuit including a resistance, a capacitance, an npn transistor and a first current-limiting resistance. During the plugging in or the unplugging out of the earphone, any momentary logic high of the detect pin charges the capacitance, the capacitance discharges when the detect pin is set to be logic low. For a period, the npn transistor is kept on, the connector of the npn transistor is set to be logic low, the input port of the mute circuit is set to be logic low, thereby the mute circuit is controlled to perform the mute mode during the period to eliminate the popping noises of connection and disconnection.