| 摘要 |
PURPOSE:To reduce loss and miniaturize the external form of a rectifier circuit, by a method wherein a MOSFET is employed in the rectifier circuit to reduce a voltage drop upon rectifying to one by several value. CONSTITUTION:A rectifier circuit consists of a resistor 1, an AC power source 2, a DC power source 3, a MOSFET 4a with a parasitic diode 46, a light emission diode 6a, a photo-transistor 6b and the like. According to this constitution, the light emission diode 6a is lighted to put the photo-transistor 6b ON when the polarity of the AC power source 2 is under a condition that a positive voltage is impressed on the drain of the MOS-. FET 4a, whereby the drain sources of said FET 4a are short-circuited. When the polarity is under a condition that a negative voltage is impressed, the light emission diode doer not light and the photo-transistor 6a turns OFF. As a result, the MOSFET 4a turns ON and a resistor 1 conducts through the AC power source 2 and the MOSFET 4a, whereby the voltage drop of the resistor becomes much lower compared with the diode.
|
