Synchronous rectifier controlling module and method for controlling a synchronous rectifier

Patent metadata

Field	Value
Publication number	US-9350262-B1
Application number	US-201514705594-A
Country	US
Kind code	B1
Filing date	May 6, 2015
Priority date	May 6, 2015
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

A synchronous rectifier controlling module includes a signal-processing unit and a plurality of driving units, the signal-processing unit is coupled with a secondary winding of a power transformer, and the driving units are electrically connected to a plurality of switch groups, each switch group includes a plurality of power switches. The signal-processing unit measures a current flowing through the secondary winding and determined operation mode of each of the power switches. When the current is increased from a first determined level to the second determined level, the synchronous rectifier controlling module makes an amount of the power switches of each of the switch groups turn on and off by following the driving signal increase accordingly.

First claim

What is claimed is:

1. A synchronous rectifier controlling module configured to control a synchronous rectifier electrically connected to a secondary winding of a power transformer, the synchronous rectifier comprising a plurality of switch groups, and each of the switch groups comprising a plurality of power switches, the synchronous rectifier controlling module comprising:
a signal-processing unit electrically connected to the secondary winding, the signal-processing unit configured to measure a current flowing through the secondary winding and determine operation modes of the power switches of each of the switch groups; and
a plurality of driving units electrically connected to the power switches of each of the switch groups and the signal-processing unit;
wherein when the current is smaller than a first determined level, the synchronous rectifier controlling module makes one power switch of each switch groups turn on and off by following a waveform of a driving signal outputted from each driving unit, when the current is larger than a second determined level, the synchronous rectifier controlling module makes all of the power switches of each of the switch groups turn on and off by following the waveform of the driving signal, and when the current is increased from the first determined level to the second determined level, the synchronous rectifier controlling module makes an amount of the power switches of each of the switch groups turn on and off by following the driving signal increase accordingly.

2. The synchronous rectifier controlling module in claim 1 , wherein the signal-processing unit comprises a current-sensing terminal, a plurality of driving-signal outputting terminals, and a plurality of controlling-signal outputting terminals, the current-sensing terminal is coupled with the secondary winding of the power transformer, each driving unit comprises a driving-signal inputting terminal, a plurality of controlling-signal inputting terminals, and a plurality of outputting terminals, the driving-signal outputting terminals of the signal-processing unit are electrically connected to the driving-signal inputting terminals of the driving units, the controlling-signal outputting terminals of the signal-processing unit are electrically connected to controlling-signal inputting terminals of each of the driving units, respectively, and the outputting terminals of each of the driving units are electrically connected to power switches of each of the switch groups.

3. The synchronous rectifier controlling module in claim 2 , wherein an amount of the controlling-signal inputting terminals is P, an amount of the outputting terminals is Q, and the following condition is satisfied:
P=Q− 1.

4. The synchronous rectifier controlling module in claim 2 , wherein the signal-processing unit comprises a signal processor and a pulse-width-modulating controller, the signal processor comprising the current-sensing terminal and the controlling-signal outputting terminals, and the pulse-width-modulating controller comprising the driving-signal outputting terminals.

5. The synchronous rectifier controlling module in claim 4 , wherein each driving unit is assembled with a main driver and a slave driver, and comprises a first controlling-signal inputting terminal, a second controlling-signal inputting terminal, and a third controlling-signal inputting terminal, the main driver and the slave drive respectively comprises a first driving-signal inputting terminal, a second driving-signal inputting terminal, a first controlling-signal inputting terminal, a second controlling-signal inputting terminal, a first driving-signal outputting terminal, and a second driving-signal outputting terminal, the first drive-signal inputting terminals and the second drive-signal inputting terminals of the main driver and the slave driver are electrically connected to each other and acted as the driving-signal inputting terminal of each driving unit, the second controlling-signal inputting terminal of the main drive is acted as the first controlling-signal inputting terminal of each driving unit, the first controlling-signal inputting terminal of the slave drive is acted as the second controlling-signal inputting terminal of each driving unit, and the second controlling-signal inputting terminal of the slave drive is acted as the third controlling-signal inputting terminal of each driving unit.

6. The synchronous rectifier controlling module in claim 4 , wherein each driving unit is assembled with a main driver and a slave driver, and comprises a first controlling-signal inputting terminal, a second controlling-signal inputting terminal, and a third controlling-signal inputting terminal, the main driver and the slave drive respectively comprises a first driving-signal inputting terminal and a first driving-signal outputting terminal, the slave driver further comprises a second driving-signal inputting terminal, a third driving-signal inputting terminal, a first controlling-signal inputting terminal, a second controlling-signal inputting terminal, a third controlling-signal inputting terminal, a second driving-signal outputting terminal, and a third driving-signal outputting terminal, the first drive-signal inputting terminals of the main driver and slave driver, the second drive-signal inputting terminal, and the third driving-signal inputting terminal of the slave driver are electrically connected to each other and acted as the driving-signal inputting terminal of each driving unit, the first controlling-signal inputting terminal of the slave drive is acted as the first controlling-signal inputting terminal of each driving unit, the second controlling-signal inputting terminal of the slave drive is acted as the second controlling-signal inputting terminal of each driving unit, and the third controlling-signal inputting terminal of the slave drive is acted as the third controlling-signal inputting terminal of each driving unit.

7. The synchronous rectifier controlling module in claim 4 , wherein each driving unit is assembled with a driver and a switching component, and comprises a first controlling-signal inputting terminal, a second controlling-signal inputting terminal, and a third controlling-signal inputting terminal, the main driver comprises a first driving-signal inputting terminal, a second driving-signal inputting terminal, a third driving-signal inputting terminal, a fourth driving-signal inputting terminal, a first driving-signal outputting terminal, a second driving-signal outputting terminal, a third driving-signal outputting terminal, and a fourth driving-signal outputting terminal, the first driving-signal inputting terminal, the second driving-signal inputting terminal, the third driving-signal inputting terminal, and the fourth driving-signal inputting terminal are electrically connected to each other and aced as the driving-signal inputting terminal of each driving unit, the switching component comprises a first switching-inputting terminal, a second switching-inputting terminal, a third switching-inputting terminal, a fourth switching-inputting terminal, a first switch-enable terminal, a second switch-enable terminal, a third switch-enable terminal, a fourth switch-enable terminal, a first switch-outputting terminal, a second switch-outputting terminal, a third switch-outputting terminal, and a fourth switch-outputting terminal, the first to fourth switching-inputting terminals are electrically connected to the first to fourth driving-signal outputting terminals, the second to fourth switch-enable terminals are electrically connected to the second to fourth controlling-signal inputting terminals, and the first to fourth first switch-outputting terminals are acted as the first to fourth outputting terminals of each dr

Assignees

• Chicony Power Tech Co Ltd

Inventors

• Hsiao Yung-Hung
• Hu Chih-Kuan

Classifications

• H02M7/217 Primary

  using semiconductor devices only · CPC title

• Y02B70/10

  Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes · CPC title

• H02M3/33592

  having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer · CPC title