CHARGING CONTROL DEVICE AND ELECTRONIC APPARATUS USING SAME

• US 20100244779A1
• Filed: 09/30/2008
• Published: 09/30/2010
• Est. Priority Date: 10/04/2007
• Status: Abandoned Application

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Hara, Hideo
• Application Number:
  US12/680,222
• Publication Number:
  US 20100244779A1
• Time in Patent Office: Days
• US Class Current: 320/152
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007192 in response to temperature
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A charging control device (1) of the present invention monitors a charging current (I3) for a secondary battery (3) and controls the charging of the secondary battery (3) such that the current value of the charging current is equal to which of a target value preset within the device and a target value freely set from an outside of the device is smaller.

Claims

1. A charging control device arranged to monitor a charging current for a secondary battery and to control charging of the secondary battery such that a current value of the charging current is equal to whichever of a target value preset within the device and a target value freely set from outside the device is smaller.

2. The charging control device of claim 1, arranged such that at least a target value corresponding to an ambient temperature, a target value corresponding to a consumption current of a system and a target value corresponding to a standard of an externally connected power supply source are preset within the device, and the charging of the secondary battery is controlled such that the current value of the charging current is equal to whichever of the target values preset within the device and the target value freely set from outside the device is smaller.

3. The charging control device of claim 2 arranged such that the target value corresponding to the ambient temperature is set such that, as the ambient temperature is higher, the target value corresponding to the ambient temperature is decreased.

4. The charging control device of claim 3 comprising a temperature sensor to detect the ambient temperature, wherein the temperature sensor includes a pair of PNP bipolar transistors that are operated at different emitter current densities, and arranged to produce an oppositely varying temperature detection signal by utilizing a fact that a difference between base-emitter voltages of the transistors varies with the ambient temperature.

5. An electronic apparatus comprising:

a secondary battery; and

the charging control device of claim 1,

wherein charging of the secondary battery is controlled by the charging control device.

6. An electronic apparatus comprising:

a secondary battery; and

the charging control device of claim 2,

wherein charging of the secondary battery is controlled by the charging control device.

7. An electronic apparatus comprising:

a secondary battery; and

the charging control device of claim 3,

wherein charging of the secondary battery is controlled by the charging control device.

8. An electronic apparatus comprising:

a secondary battery; and

the charging control device of claim 4,

wherein charging of the secondary battery is controlled by the charging control device.