Transformer coupled pard bucker for DC power supplies

• US 4,667,279 A
• Filed: 04/01/1986
• Issued: 05/19/1987
• Est. Priority Date: 04/01/1986
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Company (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Maier, Craig P.
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): JONES, JUDSON
• Application Number:
  US06/847,083
• Time in Patent Office: 413 Days
• Field of Search: 363/39, 363/75, 363/82, 363/90, 363/46, 363/126
• US Class Current: 363/46
• CPC Class Codes: H02M 1/15 using active elements

Abstract

A noise reduction circuit for a DC power supply in which the input of a high pass filter is coupled to the output circuit of the supply so as to receive a noise signal, the output of the high pass filter is coupled to the primary winding of a transformer via an amplifier, and the secondary winding of the transformer is coupled to the output circuit of the supply so as to reduce the noise therein.

Claims

1. A DC power supply in which noise appears in an output thereof, comprising

means including a high pass filter coupled to said output for deriving a signal corresponding to the noise at said output,

a transformer having primary and secondary windings,

means including an amplifier for coupling said primary winding to said means for deriving a signal corresponding to the noise, and

means for coupling said secondary winding to said output so as to reduce the noise therein.

2. A DC power supply as set forth in claim 1 having

means for producing a regulated direct current voltage across said output,

said high pass filter having an input coupled across said output circuit and an output coupled to said amplifier, and wherein

said last means connects said secondary winding to said output to vary the voltage appearing thereacross in accordance with the noise.

3. A DC power supply as set forth in claim 1 having

means for providing a regulated direct current at said output when a load is connected thereacross,

a resistor connected to said output so as to be traversed by any regulated load current,

said high pass filter having an input coupled across said resistor, and

said last means connecting said secondary winding across said output.