US 6,597,221 B2
Power converter circuit and method for controllingGeneral
US 6,597,221 B2
Power converter circuit and method for controlling
Tech Center:
2800 Semiconductors/Memory, Circuits/Measuring and Testing, Optics/Photocopying, Printing/Measuring and Testing
Examiner:
My-Trang Nu Ton
Art Unit:
2816 Semiconductors/Memory
Agent:
Inventors:
Jefferson W. Hall; Jade H. Alberkrack
Assignee:
Priority:
12/14/98
Filed:
06/28/02
Granted:
07/22/03
Expiration:
12/27/18
Abstract
A power converter circuit (23) and a method for controlling current in a transformer (16). The power converter circuit (23) includes a controller circuit (60), a duty cycle detector circuit (61), a soft start circuit (62), and a switch (63). The switch (63) controls the current in the transformer (16). The controller circuit (60) cooperates with the soft start circuit (62) to alter the duty cycle of the switch (63). During initial start-up, the switch (63) operates at a minimum duty cycle and increases towards a maximum duty cycle to prevent transformer (16) saturation and potential failure of the switch (63). In addition, the duty cycle detector circuit (61) alters the frequency at which the switch (63) turns on and off to reduce the power consumption of the power converter circuit (23).
Cooperative Patent Classification (CPC)
H02H02M3/33523H02M