JPH0461923U

JPH0461923U -

Info

Publication number: JPH0461923U
Application number: JP10370090U
Authority: JP
Priority date: 1990-10-02
Filing date: 1990-10-02
Publication date: 1992-05-27

Description

[Brief explanation of drawings]

第１図、第２図はこの考案の一実施例を示す構
成図、第３図、第４図は、従来の駆動回路の構成
図である。各図において１は入力端子、２は入力バツフア
回路、３は制御端子付電流源、４，７，８，１２
はトランジスタ、５はバイアス用電源、６は受光
素子、７は発光素子、１０は受光素子６の等価容
量、１１は可変抵抗、１３は抵抗である。なお、
図中同一符号は同一、又は相当部分を示す。 FIGS. 1 and 2 are block diagrams showing one embodiment of this invention, and FIGS. 3 and 4 are block diagrams of conventional drive circuits. In each figure, 1 is an input terminal, 2 is an input buffer circuit, 3 is a current source with a control terminal, 4, 7, 8, 12
5 is a transistor, 5 is a bias power supply, 6 is a light receiving element, 7 is a light emitting element, 10 is an equivalent capacitance of the light receiving element 6, 11 is a variable resistor, and 13 is a resistor. In addition,
The same reference numerals in the figures indicate the same or corresponding parts.

Claims

[Claims for Utility Model Registration] (1) A current source that generates a current corresponding to an input signal, a common base amplifier in which the current source is connected to the output side and a light receiving element is connected to the input side, and a current source of the current source. and means for driving a light emitting element by amplifying the difference between the current flowing through the common base amplifier and the common base amplifier, and means for causing the light receiving element to receive a part of the optical output of the light emitting element. Element drive circuit. (2) A current source that generates a current corresponding to an input signal, a gate-grounded FET amplifier in which the current source is connected to the output side and a light receiving element is connected to the input side, and the current of the current source and the gate-grounded FET amplifier are connected to each other. means for amplifying the difference between the current flowing through the light emitting element and the light emitting element;
A light emitting element drive circuit comprising: a state in which the light receiving element receives part of the light output from the light emitting element. (3) A current source that generates a current corresponding to the input signal, a common base amplifier with the current source connected to the output side and a photodetector connected to the input side, and a common base amplifier bias that provides a base voltage corresponding to the input signal. a circuit, means for amplifying the difference between the current of the current source and the current flowing through the common base amplifier to drive a light emitting element, and means for causing the light receiving element to receive a part of the optical output of the light emitting element. A light emitting element drive circuit comprising: (4) A current source that generates a current corresponding to the input signal, a gate-grounded FET amplifier in which the current source is connected to the output side and a light receiving element is connected to the input side, and a gate-grounded FET that provides the gate voltage corresponding to the input signal. an amplifier bias circuit, a means for amplifying the difference between the current of the current source and the current flowing through the common gate FET amplifier to drive a light emitting element, and a part of the optical output of the light emitting element being received by the light receiving element. A light-emitting element drive circuit characterized by comprising: means.