| 摘要 |
<p>PROBLEM TO BE SOLVED: To rapidly discharge an electric charge remaining in a cassette when the supply of a power supply is stopped, and also to perform a proper start operation when the supply of the power supply is started again even when the supply of the power supply other than the operation of a power supply switch and the stopping of the power supply occurs in a power supply start and stop control circuit provided in a load drive circuit in which the power supply is supplied and stopped by detaching and attaching, for example, the cassette.SOLUTION: When a discharge transistor 113 (Q4) configuring a discharge circuit detects that a reset circuit 107 (RES1) detects that a logical voltage Vdd (5 V) is made small as compared to a logical voltage threshold value (4 V) due to the removal of the cassette or the like, a discharge transistor 109 (Q3) is turned OFF. As a result, the voltage due to the charge charged on a load 118 or a capacitor 117 (C1) connected to the load 118 is applied to a base terminal, and the discharge transistor 109 (Q3) is turned ON. The discharge circuit quickly discharges the charged charge.</p> |
