公开(公告)号：WO2004004114A3

公开(公告)日：2004-04-29

申请号：PCT/US0320190

申请日：2003-06-26

Applicant: GIBSON GUITAR CORP

Inventor： MENDENHALL ERIC

IPC: H03F1/52 ,  H03F3/30 ,  H02H7/00

CPC classification number: H03F3/3069 ,  H03F1/52

Abstract: A system and method for protecting an output transistor in an audio amplifier output stage includes a protection circuit (10) that protects the output transistor (22) from excessive currents and voltages, and does not interfere with the normal operation of the output transistor (22). The protection circuit (10) generates an estimate of the power dissipated by the output transistor (22), adjusts that estimate so that it varies with the temperature of the output transistor, and filters the time varying power estimate to obtain a filtered estimate of the power dissipated by the output transistor. When the filtered estimateexceeds a predetermined transistor power limit, the protection circuit (10) reduces the power dissipated by the output transistor (22).

Abstract translation: 一种用于保护音频放大器输出级中的输出晶体管的系统和方法包括保护电路（10），其保护输出晶体管（22）免受过大的电流和电压的影响，并且不干扰输出晶体管（22）的正常操作 ）。 保护电路（10）产生由输出晶体管（22）耗散的功率的估计，调整该估计以使其随着输出晶体管的温度变化，并且对时变功率估计进行滤波以获得 输出晶体管的功耗。 当滤波后的估算值超过预定的晶体管功率极限时，保护电路（10）减小输出晶体管（22）耗散的功率。