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:
Apr. 04, 1995
Filed:
Jul. 27, 1994
Kazunori Nishijima, Tokyo, JP;
NEC Corporation, , JP;
Abstract
A level detecting circuit includes an operational amplifier, a first resistor, a first series circuit of second and third resistors, a fourth resistor, and a second series circuit of fifth and sixth resistors. The operational amplifier receives differential outputs from an AGC detecting circuit as inverting and non-inverting inputs. The first resistor is connected between one differential output of the AGC detecting circuit and the inverting input of the operational amplifier. The first series circuit is inserted in a negative feedback loop between an output of the operational amplifier and the inverting input of the operational amplifier. The fourth resistor is connected between the other differential output of the AGC detecting circuit and the non-inverting input of the operational amplifier. The second series circuit is connected between a bias voltage and the non-inverting input of the operational amplifier. The resistances of the first and fourth resistors and resistances of the second, third, fifth, and sixth are respectively set to be the same, and a temperature coefficient of each of the first, second, fourth, and fifth resistors and a temperature coefficient of each of the third and sixth resistors are set to have the same absolute value and opposite polarities.