Abstract: The present disclosure relates to a controller and a controlling method of a switching power supply. The controller of the switching power supply is used for turning on and off a power transistor so that inductor current flows through an inductor which is connected in series with the power transistor. The controller includes a frequency-jittering signal generating circuit, a superimpose circuit and a first comparator. The frequency-jittering signal generating circuit generates a frequency-jittering signal variable over time. The superimpose circuit superimposes the frequency-jittering signal on a sampling signal of the inductor current to generate a superimposed signal. The first comparator compares the superimposed signal with a control voltage to generate an OFF signal for turning off the power transistor. The controller of the switching power supply reduces conducted electromagnetic interference by a frequency-jittering control on the sampling signal of the inductor current.

Abstract: A method of controlling an isolated converter can include: (i) sampling and holding an output voltage of the isolated converter during a present switching cycle to generate a reference voltage signal that is proportional to the output voltage; (ii) comparing, in a predetermined time interval before a next switching cycle, the output voltage against the reference voltage signal, and activating a wake-up signal when the output voltage is less than the reference voltage signal, in order to control a voltage at a secondary winding to represent a variation of the output voltage; (iii) detecting a voltage of the primary winding or the secondary winding, and generating a voltage detection signal; and (iv) controlling the power switch according to the voltage detection signal, in order to maintain the output voltage as an expected voltage.

Abstract: A power adapter to receive at least one AC input power and transform to DC primary output power includes a power factor correction circuit to receive the AC input power and modulate to become a modulated power, an isolation voltage step-down circuit connecting to the power factor correction circuit to modulate the modulated power to a modulated lower voltage power, a switch voltage regulation circuit connecting to the isolation voltage step-down circuit to receive the modulated lower voltage power, and a voltage stabilization circuit connecting to the switch voltage regulation circuit. The switch voltage regulation circuit sets a determined output level and regulates the modulated lower voltage power to become a determined power at the determined output level. The voltage stabilization circuit modulates the determined power to become the primary output power and supplies the primary output power to a primary output end.

Abstract: A phase shift control method for a boost converter and circuit implementation comprises a master phase and at least one slave phase. A master-phase inductor current flowing through the master phase has a master-phase charge time interval and a master-phase discharge time interval; a slave-phase inductor current flowing through the slave phase has a slave-phase charge time interval and a slave-phase discharge time interval. The method comprises: calculating an ideal switching timing whereat the slave-phase inductor current descends to a zero-current judgment value; obtaining a physical switching timing whereat the slave-phase charge time interval starts; calculating a conduction timing error between the physical switching timing and the ideal switching timing; determining the time length of the slave-phase charge time interval in the same cycle according to the conduction timing error and the master-phase charge time interval.

Abstract: A phase shift control method for a boost converter and circuit implementation comprises a master phase and at least one slave phase. A master-phase inductor current flowing through the master phase has a master-phase charge time interval and a master-phase discharge time interval; a slave-phase inductor current flowing through the slave phase has a slave-phase charge time interval and a slave-phase discharge time interval. The method comprises: calculating an ideal switching timing whereat the slave-phase inductor current descends to a zero-current judgment value; obtaining a physical switching timing whereat the slave-phase charge time interval starts; calculating a conduction timing error between the physical switching timing and the ideal switching timing; determining the time length of the slave-phase charge time interval in the same cycle according to the conduction timing error and the master-phase charge time interval.

Abstract: A power adapter to receive at least one AC input power and transform to DC primary output power includes a power factor correction circuit to receive the AC input power and modulate to become a modulated power, an isolation voltage step-down circuit connecting to the power factor correction circuit to modulate the modulated power to a modulated lower voltage power, a switch voltage regulation circuit connecting to the isolation voltage step-down circuit to receive the modulated lower voltage power, and a voltage stabilization circuit connecting to the switch voltage regulation circuit. The switch voltage regulation circuit sets a determined output level and regulates the modulated lower voltage power to become a determined power at the determined output level. The voltage stabilization circuit modulates the determined power to become the primary output power and supplies the primary output power to a primary output end.