| 摘要 |
A tape end detector includes a first resistor connected between a positive power source and an analog input terminal, a second resistor connected between the analog input terminal and the ground, a first phototransistor the collector of which is connected to an output terminal and the emitter of which is connected to the analog input terminal, and a second phototransistor the collector of which is connected to the analog input terminal and the emitter of which is connected to the output terminal. In the tape end detector, it is determined based upon voltage applied to the analog input terminal when the output terminal is at a high level whether the first phototransistor is turned on or off and it is determined based upon voltage applied to the analog input terminal when the output terminal is at a low level whether the second phototransistor is turned on or off.
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