| 摘要 |
PURPOSE:To prevent the production of wasteful power consumption by alternately conducting two switches in response to the polarity of a voltage which is generated at a feedback coil, thereby removing the AC component of the current flowing through the base of a transistor. CONSTITUTION:When a transistor TR1 becomes ON state, the a side of the feedback coil Nf becomes high voltage, the resistance between the drain and the source of the FET1 becomes large, a transistor TR3 becomes ON, and a DC current is supplied to the base of the transistor TR1 through the resistor R3. When the polarity of the feedback coil Mf is inverted, the resistance between the drain and the source of the FET2 contrarily becomes large this time, the transistor TR2 becomes ON, and the DC current flows through the base. Two switches (TR3, TR4) are alternately conducted as above, thereby eliminating the flow of the DC current through the base of the transistor. |
