SEMICONDUCTOR DEVICE FOR SWITCHING POWER SUPPLY AND AC-DC CONVERTOR

• Main Authors: ARIMA SATOSHI, MURATA YUKIO, MATSUDA HIROKI
• Format: Patent
• Language: Chinese; English
• Published: 14.04.2020
• 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; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION

The present invention provides a semiconductor device for switching power supply and an AC-DC converter, which can increase the average power efficiency and reduce the size of the power supply device.The semiconductor device for the switching power supply includes a first external terminal to which a feedback voltage is input, a second external terminal to which a voltage induced in an auxiliarycoil is input, a circuit for generating a timing signal for turning on a switching element based on the voltages of the first external terminal and the second external terminal, a circuit for generating a timing signal for turning off the switching element, and a driving pulse generating circuit for generating a pulse signal based on output signals of the circuits. The turning-on timing generatingcircuit is provided with a bottom detection circuit for detecting a minimum point of the voltage of the second external terminal, and a timer circuit, and operates in a PWM mode when the timing of the output of the timing circ