Dialog Semiconductor Gmbh

Juyoung Yoon

Pengju Kong

Tao Li

Fuqiang Shi

David H Nguyen

Jianming Yao

Yimin Chen

Xiaolin Gao

Guang Feng

Kai-Wen Chin

Mengfei Liu

Ping Lo

Jiandong Zhang

Qingqing Zong

Yong Xiong Lin

A flyback converter is provided that detects a load-transient-produced increase in the output current to more quickly detect and respond to the load transient.

Flyback converter with fast load transient detection

A flyback converter is provided that compares a drain-to-source voltage of a synchronous rectifier switch transistor to a negative threshold voltage to detect whether the synchronous rectifier switch transistor has a partially-open or an open fault condition. The flyback converter also compares a gate terminal voltage of a gate driver to the synchronous rectifier switch transistor to a positive threshold voltage to detect whether the synchronous rectifier switch transistor has a gate open or a gate short-circuit fault condition.

Flyback converter with synchronous rectifier switch fault detection

A secondary-side control loop for a flyback converter is provided that generates a secondary-side control signal during normal operation using a compensator. In periods of significant load changes, the compensator is bypassed so that the secondary-side control signal is generated as an open-loop signal.

Flyback converter with improved dynamic load response

A flyback converter is disclosed having a secondary side controller that generates an input current for an optocoupler diode by driving a variable resistor with a control voltage. The secondary side controller varies a variable resistance for the variable resistor to compensate for current transfer ratio gain variations for the optocoupler.

Optocoupler current transfer ratio compensation

Systems, devices, and methods are provided to enable power converters to use two or more sensing elements to reliably detect a short circuit (or soft-short circuit) existing in the power converter and distinguish these conditions from other operating conditions, such as low voltage conditions or normal operating conditions. The disclosed embodiments enable the accurate detection of fault conditions, such as short circuits or soft short conditions, using a number of sensing elements, such as sense resistors and the inherent resistance of switching devices, while preventing the detection of false positives due to other factors such as low input voltage.

Sense resistor short detection for switching power converters

A switching power converter controller is provided that transitions between constant voltage pulse frequency modulation operation and constant current operation responsive to a comparison of a peak voltage for the constant voltage pulse frequency modulation operation and a peak voltage for the constant current operation.

Pulse frequency modulation mode transitions for single stage power converter

Embodiments described herein describe a power supply controller configured to control a power supply that provides power to an output load via a power supply transformer. The power supply controller includes a first terminal that provides supply voltage to the controller. The controller also includes a second terminal coupled to a switch external to the controller, the switch is part of a power converter controlled by the controller, wherein the second terminal is used for an initial power up of the power converter when the switch is turned on and used for a second functionality when the switch is turned off.

Multi-function terminal configurable to implement two functionalities

In one aspect, a switching power converter is described that includes a transformer, a switch, and a controller that generates a control signal to turn on and turn off the switch. For each alternating current (AC) half-cycle of an input voltage, the controller determines a minimum value of a signal representing an on-time of the power converter, compares the determined minimum value with a threshold value that is used to determine whether the switching power converter operates in a constant on-time mode or in a constant power mode, and adjusts the threshold value based on a result of the comparison. The controller further generates the control signal to operate the switching power converter in a constant power mode during a first time period of the AC half-cycle, the first time period representing a duration where the threshold value is larger than an instantaneous value of the first signal.

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Campbell, CA, United States of America

Juyoung Yoon