Title:
【発明の名称】電源回路
Document Type and Number:
Japanese Patent JP3061043
Kind Code:
B2
Abstract:
Disclosed is a power supply circuit for boosting drive voltage by a booster circuit, inputting the boosted voltage to the primary side of a piezoelectric transformer, and driving a load with an impedance of large temperature dependency by output voltage generated at the secondary side of the piezoelectric transformer. The circuit has: an excessively-small current detection means that outputs excessively-small current signal when load current flowing through the load is smaller than a predetermined value; a stopping means that stops the operation of the booster circuit when the excessively-small current signal is output; and a delaying means that sets a delay time according to the level of the output voltage. The stopping means determines the execution or inexecution of the operation according to the existence of the excessively-small current signal when the delay time passes.
Inventors:
Naoki Furuhashi
Shuji Yamaguchi
Shuji Yamaguchi
Application Number:
JP35299598A
Publication Date:
July 10, 2000
Filing Date:
December 11, 1998
Export Citation:
Assignee:
NEC
International Classes:
H02M3/24; H02M7/48; H02M7/537; H05B41/24; H05B41/282; H05B41/285; (IPC1-7): H02M7/48; H02M3/24; H05B41/24
Domestic Patent References:
| JP1167474A |
Attorney, Agent or Firm:
Tadao Hirata