Patent ID: 6137701
Filing Date: 2000-10-24
Classification: H02M,Y02B

Abstract:
A circuit for providing a D.C. voltage of high value from the rectified output of a rectifying bridge on a capacitor of high capacitance, and for providing low supply voltages, including:a first diode connected between the first output terminal of the rectifying bridge and a first terminal of the capacitor,first and second cascode-connected transistors, the first main terminal of the first transistor being connected to the first output terminal of the rectifying bridge, the second main terminal of the second transistor being connected to the second output terminal of the bridge,means for setting the potential of the control terminal of the first transistor to a first voltage with respect to the second terminal of the bridge,means for reducing the potential of the control terminal when the voltage on the first terminal exceeds a predetermined value,a regulation circuit connected at the connection node of the first and second transistors,a second diode connecting the connection node of the first and second transistors to the control terminal of the first transistor, anda means for applying, to the second transistor, a turn-on pulse of determined duration after the output voltage of the bridge has exceeded the determined value.