DIRECT CURRENT AMPLIFYING CIRCUIT

PURPOSE:To minimize the influence of an offset voltage by equalizing a DC input voltage to and a DC output voltage from a DC amplifying circuit to each other. CONSTITUTION:The emitter resistances RE and RE' of transistors (TR) 1 and 2 constituting a differential amplifier have nearly equal valu...

Full description

Saved in:
Bibliographic Details
Main Author ASANUMA HIROMI
Format Patent
LanguageEnglish
Published 11.09.1982
Subjects
AMPLIFIERS
BASIC ELECTRONIC CIRCUITRY
ELECTRICITY
Online AccessGet full text

Cover

More Information
Summary:PURPOSE:To minimize the influence of an offset voltage by equalizing a DC input voltage to and a DC output voltage from a DC amplifying circuit to each other. CONSTITUTION:The emitter resistances RE and RE' of transistors (TR) 1 and 2 constituting a differential amplifier have nearly equal values. Currents flowing through the TRs 1 and 2 become nearly equal. The major part of those currents is absorbed by current sources 5 and 6. An output is led out of a TR3 constituting an emitter follower. Negative feedback from the base of the TR3 to the emitter of the TR2 through a resistance RF is provided. The current source 6 absorbs the current flowing through the TR2, so no current flows through the resistance RF. Consequently, the emitter potential of the TR2 and the base potential of the TR3 become equal. When the VBE of both the TRs are considered, the input and output potentials are equal. Then, an offset voltage included in an input side is transferred to an output side as it is.
Bibliography:Application Number: JP19810031215