Switching voltage regulator pulse width modulation controller and method

• Main Authors: KAO SHUN HAU, HUANG HSIANG LIN, CHIEN MAO CHUAN, HUANG KENT
• Format: Patent
• Language: English
• Published: 22.06.2010
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CONTROL OR REGULATION THEREOF; CONTROLLING; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; PHYSICS; REGULATING; SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES

A PWM controller for controlling a switching voltage regulator comprises a first comparator, a second comparator and a third comparator. The first comparator is configured to detect voltages of a first node and a second node so as to determine whether to stop the PWM controller. The PWM controller is stopped if a first potential is lower than a threshold, and the first potential derives from the voltage of the first node by a level shift of a first voltage difference. The second comparator is configured to detect the voltage of the first node and then to compare the voltage with a power reference voltage so as to determine whether the PWM controller receives necessary power. The third comparator is configured to compare the voltage of the second node with an enable reference voltage so as to determine whether to disable the PWN controller.