Title:
ELECTRONIC APPARATUS
Document Type and Number:
Japanese Patent JP3475117
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To reduce the number of components and save space by installing a switching means in a constant-voltage circuit for supplying constant voltage to a driving circuit to allow the constant-voltage circuit to serve also for a charging circuit for supplying constant charging current to a secondary battery.
SOLUTION: When the apparatus body is operating, an off signal is supplied to TR35 to turn TR34 and TR32, TR33 off. The voltage of the collector side of the TR31 is equal to the sum (V1+V3) of the constant voltage V1 determined by a regulator 20 and the constant voltage V3 determined by a Zener diode 60. Therefore, this circuit becomes a constant-voltage circuit for driving which supplies the constant voltage (V1+V3) to an output terminal 70. When charging a secondary battery, an on signal is supplied to the TR35 to turn TR34 and TR32, TR33 off. Therefore, the voltage of the collector side of the TR31 becomes the sum (V1+V2) of the constant voltage V1 determined by the regulator 20 and the constant voltage V2 determined by the secondary battery 4. Meanwhile, the voltage of R51 is fixed at V1 and charging current becomes constant (V1/R51) and therefore this circuit becomes a constant-voltage circuit for charging for performing a constant current charging.
Inventors:
Yoshimasa Ono
Application Number:
JP8180299A
Publication Date:
December 08, 2003
Filing Date:
March 25, 1999
Export Citation:
Assignee:
Sanyo Electric Co., Ltd.
Sanyo Techno Sound Co., Ltd.
Sanyo Techno Sound Co., Ltd.
International Classes:
H02J7/34; (IPC1-7): H02J7/34
Domestic Patent References:
| JP8130836A | ||||
| JP6412826A | ||||
| JP1169647A | ||||
| JP9285026A | ||||
| JP5186517U |
Attorney, Agent or Firm:
Masamasa Shibano