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:
Jul. 14, 1981
Filed:
Mar. 20, 1979
Hiroyasu Kishi, Gunma, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Tokyo Sanyo Electric Co., Ltd., Gunma, JP;
Abstract
An input signal could include a pulsive noise such as an ignition noise in superposition on a continuous noise such as a white noise. Such input signal is commonly applied to the respective base electrodes of paired transistors of the same conductivity type connected in a differential amplifier fashion. The amplified signal is then applied to a rectifying circuit, where the signal is full-wave rectified, and the output of the rectifying circuit is detected by a detector. The detected output is then applied to the base electrode of a first transistor. A second transistor is provided such that a current mirror circuit is formed between the collector electrode of the second transistor and the collector electrode of the first transistor. A diode circuit is connected between the current mirror circuit and the collector electrode of the second transistor in the forward direction. The diode circuit comprises a parallel connection of two diode-series connections, the junction of one diode-series connection being connected to the base electrode of one of the paired transistors and the junction of the other diode-series connection being connected to the base electrode of the other transistor of the paired transistors. The output of the rectifying circuit is further applied to a pulsive noise detecting circuit, which is adapted to level detect the noise at a predetermined level higher than the level of the continuous noise, thereby to detect presence or absence of a pulsive noise.