US 7,834,605 B2
Method and apparatus for maintaining a constant load current with line voltage in a switch mode power supplyGeneral
US 7,834,605 B2
Method and apparatus for maintaining a constant load current with line voltage in a switch mode power supply
Tech Center:
2800 Semiconductors/Memory, Circuits/Measuring and Testing, Optics/Photocopying, Printing/Measuring and Testing
Examiner:
Rajnikant B Patel
Art Unit:
2839 Electrical Circuits and Systems
Inventors:
Balu Balakrishnan; Alex B. Djenguerian; Kent Wong; David Michael Hugh Matthews
Assignee:
Priority:
09/27/01
Filed:
10/16/09
Granted:
11/16/10
Expiration:
12/19/22
Abstract
A power supply regulator including a variable current limit threshold that increases during an on time of a switch. In one aspect, a power supply regulator includes a comparator that has a first input coupled to sense a voltage representative of a current flowing through a switch during an on time of the switch. The comparator has a second input coupled to receive a variable current limit threshold that increases during the on time of the switch. A feedback circuit is coupled to receive a feedback signal representative of an output voltage at an output of a power supply. A control circuit is coupled to generate a control signal in response to an output of the comparator and in response to an output of the feedback circuit. The control signal is to be coupled to a control terminal of the switch to control switching of the switch.
Cooperative Patent Classification (CPC)
H02H02M3/33523H02MH03K17/0822H03K