Electrical apparatus, computer, power switching unit, and power switching method

• US 20030085626A1
• Filed: 10/29/2002
• Published: 05/08/2003
• Est. Priority Date: 10/29/2001
• Status: Active Grant

• Current Assignee: Lenovo Singapore Pte Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Odaohhara, Shigefumi
• Granted Patent: US 7,057,309 B2
• Time in Patent Office: Days
• US Class Current: 307/150
• CPC Class Codes: G06F 1/263 Arrangements for using multiple switchable power supplies, e.g. battery and AC G06F1/30 takes precedence
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices

Abstract

An electrical apparatus including an AC adapter 51; a battery 52 that repeats charging and discharging to power the apparatus; an AC/DC enable circuit 61 that switches between stop and start of power source from the AC adapter 51 to the body; a charger utilization circuit 62 that charges an output capacitor (Cout) of a charger 60 while the power source from the AC adapter 51 stops; and a battery detection circuit 63 that detects disconnection of the battery 52. If the battery 52 is disconnected from the body and the battery detection circuit 63 detects the disconnection while the power source from the AC adapter 51 stops and the body is powered by the battery 52, the AC/DC enable circuit 61 starts power source to the body while the body is powered by the output capacitor (Cout).

Claims

1. ) A power supply for an electrical apparatus, said power supply comprising:

an input for receiving power from a commercial power source;

an output for delivering power to the electrical apparatus;

a switch for selectively coupling said input to said output

a removable battery coupled to said output;

a circuit for detecting removal of said battery and for activating said switch to couple said input to said output upon detection of the removal of said battery.

2. ) The power supply of claim 1, further comprising:

a capacitive circuit for storing electrical energy, said capacitive circuit being coupled to said output, said capacitive circuit temporarily supplying power to said output in response to the removal of said battery.