| 摘要 |
PROBLEM TO BE SOLVED: To reduce the number of control ports required for an amplifier and a microcomputer that controls the amplifier.SOLUTION: A mute control circuit 1 includes: a control line 7 connecting a hysteresis circuit 6 with an amplifier 201; a control line 8 connecting a microcomputer 202 with a low-voltage detection circuit 3; a control line 9 connecting the control line 7 with the control line 8; and a Zener diode D12 which is provided on the control line 8 and whose cathode is connected with a cathode of a Zener diode D2 and whose anode is connected with the microcomputer 202.SELECTED DRAWING: Figure 1 |
