DRIVING DEVICE

• Main Author: TODA AKIHIKO
• Format: Patent
• Language: English; Japanese
• Published: 05.07.2018
• Subjects: DEAF-AID SETS; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKEACOUSTIC ELECTROMECHANICAL TRANSDUCERS; PUBLIC ADDRESS SYSTEMS

PROBLEM TO BE SOLVED: To prevent oscillation even in the case where characteristics of a speaker are fluctuated or varied, to suppress a distortion by continuously changing a control signal, and to reduce cost.SOLUTION: A driving device 100 comprises: an addition part 10 for adding an input signal V1 and a feedback signal V2; an amplification part 11 for driving a speaker 12 by amplifying an addition signal V3; a current detection part 13 for outputting a detection signal 13a corresponding to currents I running through the speaker 12; a band pass filter 14 for receiving the input of the detection signal 13a; a feedback signal generation part 15 for generating a feedback signal V2 by multiplying an output signal 14a by a coefficient; and a control part 16 for executing reduction processing for reducing the coefficient when a gain of the addition signal V3 with respect to the input signal V1 exceeds a reference value.SELECTED DRAWING: Figure 1 【課題】スピーカの特性の変動やばらつきが生じた場合でも発振を防ぎ、制御信号を連続的に変化させることにより歪みを抑え、コストを低減する。【解決手段】駆動装置１００は、入力信号Ｖ１と帰還信号Ｖ２とを加算する加算部１０と、加算信号Ｖ３を増幅してスピーカ１２を駆動する増幅部１１と、スピーカ１２に流れる電流Ｉに応じた検出信号１３ａを出力する電流検出部１３と、検出信号１３ａが入力されるバンドパスフィルタ１４と、出力信号１４ａに係数を乗算して帰還信号Ｖ２を生成する帰還信号生成部１５と、入力信号Ｖ１に対する加算信号Ｖ３のゲインが基準値を越えると、係数を減少させる減少処理を実行する制御部１６とを備える。【選択図】図１