05355073 is referenced by 90 patents and cites 36 patents.

An AC adapter including an automatic battery voltage selection circuit that senses which battery pack is installed in an electronic device and regulates the AC adapter output voltage at an appropriate level. A battery voltage selection signal providing circuit provides the battery voltage selection signal indicative of the particular battery pack present. An output voltage sensor senses the output voltage of the AC adapter and provides a proportional sense signal to a feedback circuit which controls the AC adapter output. A switching circuit coupled to the output voltage sensor and to the battery voltage selection signal providing circuit modifies the sense signal depending upon the state of the battery voltage selection signal, so that the AC adapter output voltage is regulated at an appropriate level for the particular battery pack installed. If a first battery pack is installed, the AC adapter regulates the output voltage at a first level and if a second battery pack is installed, the AC adapter output voltage is regulated at a second, higher voltage level. The switching circuit is preferably implemented with a transistor switching circuit.

Title
Battery pack sensor for an AC adapter
Application Number
7/954008
Publication Number
5355073
Application Date
September 30, 1992
Publication Date
October 11, 1994
Inventor
Hai N Nguyen
Spring
TX, US
Agent
Pravel Hewitt Kimball & Krieger
Assignee
Compaq Computer Corporation
TX, US
IPC
H02J 7/00
H01M 10/44
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