Charging-and-discharging control device, a battery pack, and an electronic apparatus with improved charge and discarge control

• US 5,801,514 A
• Filed: 01/17/1997
• Issued: 09/01/1998
• Est. Priority Date: 09/01/1994
• Status: Expired due to Term

• Current Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Original Assignee: Fujitsu Limited
• Inventors: Saeki, Mituo, Yano, Hidetoshi, Ozawa, Hidekiyo
• Primary Examiner(s): TSO, EDWARD H
• Application Number:
  US08/786,364
• Time in Patent Office: 592 Days
• Field of Search: 320/5, 320/13, 320/30, 320/39, 320/40, 320/49, 320/136, 361/89, 361/90, 361/212
• US Class Current: 320/136
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/00036 Charger exchanging data with battery
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: H02J 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/00308 Overvoltage protection
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A charging-and-discharging device in an electronic apparatus includes a rechargeable battery and a charging device for charging the battery. The charging-and-discharging device includes a switching circuit electrically isolating one terminal side of the battery from a ground side of the electronic apparatus. The charging-and-discharging device further includes a charge control section controlling the isolating of the one terminal side of the battery from the ground side of the electronic apparatus by turning off the switching circuit during charging of the battery. In the charging-and-discharging device, the one terminal side of the battery is isolated from the ground side of the electronic apparatus by the switching circuit during charging of the battery and a closed loop including the charging device and the battery is established to charge the battery.

Claims

1. A charging-and-discharging control device in a battery pack having a rechargeable battery, said charging-and-discharging control device comprising:

a switching circuit preventing over discharge of the battery;

a control section controlling to turn off said switching circuit when the over discharge of the battery is detected; and

an input terminal which receives a control signal to control said switching circuit externally of the battery pack;

wherein said control section turns off said switching circuit to stop discharging in two cases, a first case being when the over discharge of the battery is detected and a second case being when the control signal for stopping the discharging is applied to said input terminal.

2. A battery pack comprising:

a rechargeable battery; and

a charging-and-discharging control device including;

a switching circuit preventing over discharge of the battery;

a control section controlling to turn off said switching circuit when the over discharge of the battery is detected; and

an input terminal which receives a control signal to control said switching circuit externally of the battery pack;

wherein said control section turns off said switching circuit to stop discharging in two cases, a first case being when the over discharge of the battery is detected and a second case being when the control signal for stopping the discharging is applied to said input terminal.

3. An electronic apparatus operating with a battery comprising:

a battery pack supplying power from the battery, said battery pack including;

a rechargeable battery; and

a charging-and-discharging control device having;

a switching circuit preventing over discharge of the battery;

a control section controlling said switching circuit to turn off when the over discharge of the battery is detected; and

an input terminal for receiving a control signal to control said switching circuit externally of the battery pack;

wherein said control section turns off said switching circuit to stop discharging in two cases, a first case being when the over discharge of the battery is detected and a second case being when the control signal for stopping the discharging is applied to said input terminal;

power consuming circuits provided with said power of the battery from the battery pack; and

a control circuit producing the control signal for stopping the discharging to said input terminal of the battery pack.