| 摘要 |
PURPOSE:To prevent the malfunction at power supply switch switching, by providing the power supply clear circuit with the channel selection unit controlled with the microcomputer muCM to control the operation time of the muCM and the memory. CONSTITUTION:The muCM39 reads out the channel selection information stored in the CMOS memory 40 by the operation of the switch of the key matrix 37 and performs channel selection operation via the D/A conversion and the band latch circuit 41. The output signal of the power supply clear circuit 53 is fed to the muCM39 and memory 40 to turn on the power supply turning on switch to the muCM39 and the memory 40 so that the output signal of muCM and memory is risen with a given time delayed than the operation time of muCM and memory. Further, control is made with the output signal of the circuit 53 so that the output signal falls before the operation of muCM and memory is stopped through the opening of the power supply switch. Thus, the malfunction of muCM and memory due to noise at power supply switching can be prevented. |
