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:
Jun. 16, 1992
Filed:
May. 17, 1991
Kazunori Nishijima, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A detector for use in an automatic gain control amplifier and operated to generate a gain control voltage in response to an amplitude of the output signal of an amplifier circuit includes five transistors connected in a detector circuit. The first transistor receives a bias voltage at its base and the second transistor receives a true signal of an input signal along with the bias voltage at its base. The third transistor receives a complementary signal of the input signal along with the bias voltage at its base. A first current source is connected in common to the emitters of the first to third transistors. A control voltage is supplied between the bases of the fourth and fifth transistors. A second current source supplies an operating current to the fourth and fifth transistors. A first load is connected in common to the collectors of the first and the fourth transistors. A second load is connected in common to the collectors of the second, third and fifth transistors. A first output terminal of the detector is connected to the collectors of the first and fourth transistors, and a second output terminal of the detector is connected to the collectors of the second, third and fifth transistors. The detector reduces or eliminates temperature dependence of the amplitude of the output of the amplifier circuit.