| 摘要 |
PURPOSE: A power start circuit is provided to selectively flow B+ current and voltage through a PLL IC and a diode by high or low signals to shield current to a start resistor, thereby preventing resistors from being heated during normal operation and enhancing the reliability of overall system. CONSTITUTION: A power start circuit comprises a bridge rectifier(BD), a trans(T1), a diode(D1), a condenser(C1), a PLL IC, a micom, a transistor(TR) and a relay(RY). The micom outputs high and low signals for a while when a power switch is turned ON. The transistor(TR) is turned ON/OFF by high signals output for 2-3 sec and low signals output after the 2-3 sec from a micom. The relay(RY) controls current and voltage supplied to the PLL IC in accordance with the turn ON/OFF of the transistor(TR). |
