Circuit for eliminating noise

Details Circuit for eliminating noise Circuit for eliminating noise

2007-04-10

2011-12-06

Mei, Xu (Department: 2614)

Electrical audio signal processing systems and devices

Noise or distortion suppression

Soft switching, muting, or noise gating

C381S094100

Reexamination Certificate

active

08073158

ABSTRACT:
A circuit for eliminating noise includes a sound card (30) with an audio signal output, a power supply (10) for providing working voltage to the sound card, a first transistor (Q1), a second transistor (Q2), and a third transistor (Q3). The power supply has a power good pin, a PSON# pin, and a standby voltage pin. During powering on time of the sound card, the power good pin is at low level and the second transistor is therefore turned on to ground the audio signal output so as to eliminate turn-on noise. During powering down time of the sound card, the PSON# pin turns from low to high level to turn on the third transistor before the audio power for providing working voltage to the sound card is powered down, thus the first transistor turns off, and the second transistor turns on to ground the audio signal output of the sound card so as to eliminate turn-off noise.

REFERENCES:
patent: 5151942 (1992-09-01), Sasaki
patent: 5740453 (1998-04-01), Lada, Jr.
patent: 5768601 (1998-06-01), Tran
patent: 5794057 (1998-08-01), Lada, Jr.
patent: 6041416 (2000-03-01), Lada, Jr.
patent: 6768224 (2004-07-01), Shen et al.
patent: 6904373 (2005-06-01), Le et al.
patent: 2008/0151455 (2008-06-01), Ren

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