| 摘要 |
PURPOSE: To ensure the safety of a circuit by sensing over-voltage, and controlling the pause period in oscillation of the output voltage from a DC/DC converter provided in an inverter. CONSTITUTION: When a voltage 41 between the primary side of a transformer 9 and a choke coil 4 or a voltage 23 sensed by diodes 14, 15 in a tube current sensor is sensed as an over-voltage, a transistor 22 is turned on to change the resistance value for controlling the voltage between the dead time control terminal of IC 19 and GND. Thereby oscillation is continued in the condition that the IC is stopped oscillating or the duty cycle is low, and either the circuit operation should be ceased or the voltages at the over-voltage sensing points 41 and 23 are sunk to the safe state. Thus the safety of elements in the circuit is ensured. |
