Here, the large power voice circuit consisted of voice record/playback chip ISD1420, BTL power amplifier and loudspeaker. The single-chip computer received information from the main PLC and controled this part.

• 该环节利用语音存储/再生芯片ISD1420、BTL功率放大电路 及扬声器构成大功率语音电路,由单片机根据主控PLC的命令进行发声控制。