| 摘要 |
PURPOSE:To simplify the circuit configuration and reduce the size of a device by selectively switching an input signal and an output signal for an A/D converting means and using an input monitor circuit and an output monitor circuit in common. CONSTITUTION:An input circuit which includes a down signal A/D converter 23 is connected to the input side and output side of a down amplifier 14 through a changeover switch 25. When the switch 25 is switched, the signal of the amplifier 14 is inputted to the converter 23 and converted from analog to digital, and then fetched in a CPU 3. An input circuit which includes an up signal A/D converter 24, on the other hand, is connected to the input side and output side of an up amplifier 16 through a changeover switch 26. When the switch 26 is switched, the input signal and output signal of the amplifier 16 are inputted to the converter 24 and converted from analog to digital, and inputted to the CPU 3. Consequently, the input circuits which include the A/D converters can be simplified in constitution to reduce the size and cost of the device. |
