Power Forest Technology Corporation

Mediatek Corporation

Tso-Min Chen

Chien-Wei Kuan

Yen-Hsun Hsu

Chen-Yen Ho

Sheng-Hong Yan

Chia-Sheng Peng

Po-Jen Ke

Shih-Mei Lin

Che-Hao Meng

Yun-Chi Chiang

A voltage conversion apparatus for implementing zero-voltage switching based on recovering leakage inductance energy is provided. A leakage inductance energy recovery circuit is coupled to a primary side auxiliary winding and a control circuit, and recovers leakage inductance energy of a transformer circuit to supply an operating power to the control circuit. Before a main switch is turned on the next time, leakage inductance energy recovered previously is used to lower a cross-voltage of the main switch, so that transient loss of conduction of the main switch is eliminated or reduced, and circuit efficiency is improved.

Voltage conversion apparatus for implementing zero-voltage switching based on recovering leakage inductance energy

A power conversion circuit includes an input terminal, a first switching element, a second switching element, a third switching element, a fourth switching element, a capacitor; an inductor; and a controller configured to control the switching elements to be switched ON/OFF, such that a voltage at the load is regulated by repetitively (1) charging the inductor with a first current before charging the capacitor causing a second current to flow in the inductor and (2) charging the inductor with a third current before discharging the capacitor causing a fourth current to flow in the inductor.

Power conversion circuit and associated operating method

Provided is a power supply circuit for a wireless mobile device having a plurality of power amplification components. The power supply circuit includes: a first DC-DC converter, for providing at least one constant output voltage (which is provided to the power amplification components) and/or at least one DC intermediate voltage; a second DC-DC converter, for providing a DC component of at least one time-varying output voltage; and at least one linear amplifier. When the at least one linear amplifier receives the at least one DC intermediate voltage from the first DC-DC converter, the at least one linear amplifier provides at least one AC component of the at least one time-varying output voltage. The DC component and the at least one AC component of the at least one time-varying output voltage are combined into the at least one time-varying output voltage and provided to the power amplification components.

Power supply circuit of wireless mobile device

A power conversion apparatus including a flyback power conversion circuit, a control chip and a detection auxiliary circuit is provided. The flyback power conversion circuit receives and converts an AC input voltage into a DC output voltage. The control chip generates a PWM signal in response to a power supply requirement to control operations of the flyback power conversion circuit, and the control chip has a multi-function detection pin. The detection auxiliary circuit assists the control chip to obtain an auxiliary voltage related to the DC output voltage via the multi-function detection pin, and thereby determines a transition time of the PWM signal according to the auxiliary voltage. Besides, the detection auxiliary circuit assists the control chip to execute detections of an over temperature protection (OTP) and an over voltage protection (OVP) via the multi-function detection pin respectively within first and second detection phases.

Flyback-based power conversion apparatus with high conversion efficiency and low cost mechanism

A flyback-based power conversion apparatus and a power conversion method thereof are provided. By switching first and second detection switches disposed in a control chip and coupled to a multi-function pin of the control chip at different timings, the present invention applies a collocation of a voltage-current detection auxiliary circuit and a current detection circuit at a certain timing to execute a detection of the AC input voltage received by a flyback power conversion circuit, and the present invention applies a collocation of the auxiliary voltage-current detection circuit, an over temperature protection unit and an over voltage protection unit at another timing to execute detections of an over temperature protection and an over voltage protection. As the result, a single multi-function detection pin of the control pin is corresponding to a plurality of related function detections, so as to reduce the production cost of manufacturing the control chip.

Growing community of inventors

Hsinchu, Taiwan

Tso-Min Chen