JPS585096U

JPS585096U - Sawtooth wave generation circuit for electronic musical instruments

Info

Publication number: JPS585096U
Application number: JP8290482U
Authority: JP
Inventors: 栄一郎青木
Original assignee: ヤマハ株式会社
Priority date: 1982-06-03
Filing date: 1982-06-03
Publication date: 1983-01-13

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of drawings]

第１図はこの考案の一実施例を示すブロック図、第２図
はデジタル式トーンジェネレータの一例ヲ示すブロック
図、第３図は矩形波を鋸歯状波に変換する動作を説明す
るタイミングチャート、第４図は第１図のアンプ４２及
び４３を一体化した場合の一例を示すもので、フィード
バック抵抗を音名に応じて切換えるように構成した回路
図である。１０・・・キースイッチ回路、１１・・・音名ライン、
１２〜１４・・・オクターブライン、１８・・・デジタ
ル式トーンジェネレータ、１９．２０・・・−Ｖ分周回
路、３３・・・鋸歯状波変換回路、４２．４３・・・ゲ
イン可変アンプ。FIG. 1 is a block diagram showing an embodiment of this invention, FIG. 2 is a block diagram showing an example of a digital tone generator, and FIG. 3 is a timing chart illustrating the operation of converting a rectangular wave into a sawtooth wave. FIG. 4 shows an example in which the amplifiers 42 and 43 of FIG. 1 are integrated, and is a circuit diagram configured to switch the feedback resistance according to the note name. 10... Key switch circuit, 11... Pitch name line,
12 to 14... Octave line, 18... Digital tone generator, 19.20... -V frequency dividing circuit, 33... Sawtooth wave conversion circuit, 42.43... Variable gain amplifier.

Claims

[Scope of utility model registration request]

a circuit that generates a signal indicating the octave and note name of the pressed key; a circuit that generates a pulse signal of a frequency corresponding to the pitch of the pressed key based on the signal indicating the octave and note name; and the pulse signal a sawtooth wave conversion circuit that has a capacitor whose charging and discharging is controlled by a sawtooth wave conversion circuit that generates a sawtooth wave having the same frequency as the pulse signal in response to a terminal voltage of the capacitor; an amplification circuit whose amplification degree can be controlled; and an amplification circuit which controls the amplification degree of the amplification circuit according to the pitch of the pressed key based on the signal indicating the octave and note name, and outputs a sawtooth shape from the amplification circuit. A sawtooth wave generation circuit for an electronic musical instrument, comprising a control circuit that makes the amplitude of the wave constant regardless of frequency.