JPS6424389U

JPS6424389U -

Info

Publication number: JPS6424389U
Application number: JP11897487U
Authority: JP
Priority date: 1987-08-03
Filing date: 1987-08-03
Publication date: 1989-02-09

Description

[Brief explanation of the drawing]

第１図は本考案の実施例に係る表示装置の輝度
調整回路を示す回路図、第２図は従来における表
示装置の輝度調整回路を示す回路図、第３図は第
２図のタイミングチヤート、第４図は第１図のタ
イミングチヤートである。２０……充放電回路、２３……比較器、２４…
…ＲＳ・ＦＦ、２５……電流吸込み回路。 FIG. 1 is a circuit diagram showing a brightness adjustment circuit of a display device according to an embodiment of the present invention, FIG. 2 is a circuit diagram showing a brightness adjustment circuit of a conventional display device, and FIG. 3 is a timing chart of FIG. FIG. 4 is a timing chart of FIG. 1. 20... Charge/discharge circuit, 23... Comparator, 24...
...RS/FF, 25...Current sink circuit.

Claims

[Claims for Utility Model Registration] 1. In a brightness adjustment circuit for a display device that outputs a pulse signal with a variable pulse width for driving the display device, a charging/discharging circuit with a variable time constant, and a reference to the output of this charging/discharging circuit. A comparator that compares the signal and sends out an output signal according to the comparison result; a timing circuit that inputs the output signal of this comparator and outputs a pulse signal of a predetermined pulse width in synchronization with the basic pulse; A brightness adjustment circuit for a display device, comprising: a current sink circuit that controls charging and discharging operations of the charging and discharging circuit based on pulse signals from a timing circuit. 2. The brightness adjustment circuit for a display device according to claim 1, wherein the charging/discharging circuit includes a variable resistor and a capacitor. 3. The brightness adjustment circuit for a display device according to claim 1, wherein the timing circuit is constituted by a set-reset type flip-flop circuit.