The inventor has created several power supplied to eliminate or greatly reduce the ground loop problem. The inventor has discovered that the ground loop distortion is caused by the switching from positive to negative in alternating current. What the inventor has found is that just placing a diode across the two terminals of a power supply works to eliminate distortion and the ground loop problem. In the two simplest power supplies, the inventor has places a diode across the output from a half wave inverter. This helps to eliminate the ground loop problem and other distortion. The inventor also shows three other more complicated designs for power supply which include diodes and capacitors.
This application is a division of Application Ser. No. 08/459,256 Jun. 02,1995 now U.S. Pat. No. 5,644,263 which is a division and continuation-in-part of Application Ser. No. 07/945,092, filed Sep. 15, 1992 now U.S. Pat. No. 5,422,804.
An energy-feedback clamping circuit of a power converter is proposed. The converter includes a transformer coupled to a full-wave rectifier circuit. The clamping circuit includes: two clamping diodes having two anodes coupled to each other at a common-anode terminal and two cathodes coupled to two terminals of a secondary winding of the transformer, a first clamping capacitor having a first terminal coupled to a cathode of a first rectifying diode of the rectifier circuit and a second terminal coupled to the common-anode terminal, a second clamping capacitor having a first terminal coupled to a connecting node of the output filtering inductor and capacitor of the rectifier circuit and a second terminal coupled to the common-anode terminal, and a converter circuit having an input terminal coupled to the second clamping capacitor and an output terminal for offering a power source.
The present invention uses an AC signal and an external DC control voltage to generate a plurality of levels of output DC voltages. The level of the output voltage is determined by the DC control voltage and has the opposite polarity. The invention is preferably implemented as a balanced circuit, which generates spurious signals at even harmonics of the AC frequency signal. The spurious signals can then be filtered out using a low-pass filter.
A clamp circuit for use in a DC/DC voltage converter having a first converter output including a first node and a second node, and a second converter output including a third node a fourth node. The clamp circuit includes a positive voltage output node coupled to the first node, a negative voltage output node coupled to the fourth node, a neutral voltage output node, a first diode coupled between the positive voltage output node and the third node, a second diode coupled between the negative voltage output node and the second node, a first inductor coupled between the second diode and the neutral voltage output node, and a second inductor coupled between the first diode and the neutral voltage output node.
