| 摘要 |
PURPOSE:To suppress an overcurrent by stopping the pulse output for a fixed period after the overcurrent is detected, and limiting the pulse output width in response to the magnitude of the current level. CONSTITUTION:The full-wave rectified voltage of a rectifier circuit 1 is fed to a transformer TS.4 according to the switching action of a transistor TR1 by the output pulse C of a switching drive circuit 3, and it is outputted to an output terminal O after impedance conversion. When the transistor TR1 is set to the on-state, the voltage extracted by a resistor R1 is integrated by an integrating circuit 6. If this integrated value exceeds the threshold value, a transistor TR2 is turned on, RSF/F 8 is set, and the pulse output control signal D of the H-level is outputted from an output terminal Q to the switching drive circuit 3. The switching drive circuit 3 stops the output of the pulse signal C, and the transistor TR1 is set to the off-state to stop the output. The output of the pulse signal C is stopped to stop the power output for the time length set by a timer section 9. An overcurrent is limited and suppressed by a series of actions. |
