Title:
DIRECT-CURRENT TO DIRECT-CURRENT CONVERTER
Document Type and Number:
Japanese Patent JP3397242
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To increase the efficiency of a direct-current to direct-current converter, when it is lightly loaded.
SOLUTION: Between a pair of DC terminals 18, 19 a series circuit composed of the primary winding 21 of a transformer 2, a switching element 3, and a current detecting resistor 4 is connected. To the secondary winding 22 of the transformer 2, a smoothing capacitor 7 is connected through a diode 6. In parallel with a series circuit of the switching element 3 and the current detecting resistor 4, a resonance capacitor 5 is connected. On the basis of output synthesis of a detected current signal, a detected output voltage signal, and a detected switching voltage signal 11; a control pulse for the switching element 3 is formed. In a control circuit 13, a minimum-off-period determining circuit for setting a first minimum off-period and a second minimum off-period having a hysteresis, is provided. The off-period of the switching element 3 is limited by the minimum off-period, when the converter is lightly loaded. Zero-volt switching of the switching element 3 to be performed when it is turned on, is performed after the minimum off-period elapses and discharge of stored energy in the transformer 2 finishes.
Inventors:
Tomoyasu Yamada
Application Number:
JP2000374276A
Publication Date:
April 14, 2003
Filing Date:
December 08, 2000
Export Citation:
Assignee:
Sanken Electric Co., Ltd.
International Classes:
H02M3/28; (IPC1-7): H02M3/28
Domestic Patent References:
| JP8289543A | ||||
| JP9172777A | ||||
| JP9201053A |
Attorney, Agent or Firm:
Noritsugu Takano