Portable electronic apparatus and charge controlling method for portable electronic apparatus

• US 5,777,399 A
• Filed: 12/10/1996
• Issued: 07/07/1998
• Est. Priority Date: 12/14/1995
• Status: Expired due to Term

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Shibuya, Toshiyuki
• Primary Examiner(s): Sircus, Brian
• Assistant Examiner(s): PALADINI, ALBERT WILLIAM
• Application Number:
  US08/763,987
• Time in Patent Office: 574 Days
• Field of Search: 307/66, 307/64, 307/150, 320/2, 320/3, 320/11, 320/19, 320/21, 320/22, 320/43, 364/492
• US Class Current: 307/66
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0032 disconnection of loads if battery is not under charge, e.g. in vehicle if engine is not running
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence

Abstract

Since means (control terminal a 16, control terminal b 17, control terminal c 18 and voltage detection terminal 22) for controlling portable electronic apparatus charger 2 directly from CPU 13 in the inside of portable electronic apparatus body 1 is provided, the circuit scale is reduced. Further, since means (power supply detection circuit 6, switch a 7, switch b 8 and regulator a 9) for supplying an electric current to CPU 13 to allow CPU 13 to operate with a signal from sub clock 11 even when the power supply to portable electronic apparatus body 1 is in an off state is provided, if portable electronic apparatus body 1 is connected to portable electronic apparatus charger 2, then CPU 13 and only a limited number of the other circuits in the inside of portable electronic apparatus body 1 are allowed to operate as a control circuit for portable electronic apparatus charger 2.

Claims

1. A portable electronic apparatus having a portable electronic apparatus body, a rechargeable battery, a CPU, and a portable electronic apparatus charger for charging said battery;

said portable electronic apparatus charger comprising

quick charging means having a function of quickly charging said battery, and

slow charging means having a function of slowly charging said battery,

said portable electronic apparatus body comprising

a power supply switch for switching on or off a connection from said battery to the entire circuitry of said portable electronic apparatus,

connection detection means for detecting connection of said portable electronic apparatus body to said portable electronic apparatus charger,

open/close detection means for detecting an on/off state of said power supply switch, and

auxiliary power supply means for directly supplying an electric current from said battery to said CPU when said power supply switch is off while charging of said battery is proceeding,

said CPU having

a charge completion detection function of detecting a charged state of said battery from an output voltage of said battery, and

a quick/slow switching controlling function of controlling said quick charging means to an on state and controlling said slow charging means to an off state when the charged state detected by said charge completion detection function is insufficient charge but controlling said quick charging means to an on state when the charged state detected by said charge completion detection function is sufficient charge.

2. A portable electronic apparatus as claimed in claim 1, wherein

said slow charging means includes two slow charging circuits having different output electric current values, and

said CPU having a controlling function for switching said two slow charging circuits in response to an on or off state of said power supply switch detected by said open/close detection means upon slow charging.

3. A charge controlling method for the portable electronic apparatus as claimed in claim 1, comprising the steps of

detecting connection of said portable electronic apparatus to said portable electronic apparatus charger,

detecting an on/off state of said power supply switch and turning off said auxiliary power supply means when said power supply switch is on but turning on said auxiliary power supply means when said power supply switch is off,

turning on said quick charging means,

detecting a charged state of said battery, and

turning off said quick charging means and turning on said slow charging means when the charged state of said battery reaches a predetermined value.

4. A charge controlling method for the portable electronic apparatus as claimed in claim 2, comprising the steps of

detecting connection of said portable electronic apparatus to said portable electronic apparatus charger,

detecting an on/off state of said power supply switch and turning off said auxiliary power supply means when said power supply switch is on but turning on said auxiliary power supply means when said power supply switch is off,

turning on said quick charging means,

detecting a charged state of said battery, and

turning off said quick charging means when the charged state of said battery reaches a predetermined value and turning on a predetermined one of said slow charging circuits in response to an on/off state of said power supply switch.