05859503 is referenced by 4 patents and cites 1 patents.

A lamp drive circuit periodically energizes a lamp above its rated voltage and current for rapid illumination of the lamp. In the preferred embodiment, the lamp is connected in a voltage divider and the circuit monitors the voltage drop across the lamp. The voltage drop is indicative of the lamp resistance and thereby the temperature. When the voltage drop reaches a predetermined limit corresponding to the temperature rating of the lamp, it is de-energized and allowed to cool during the remainder of the cycle thereby enabling a high modulation frequency.

Title
Lamp modulation circuit having a feedback for measuring lamp temperature
Application Number
8/831201
Publication Number
5859503
Application Date
April 2, 1997
Publication Date
January 12, 1999
Inventor
Robert Stephen Potratz
Overland Park
KS, US
Agent
Hovey Williams Timmons & Collins
Assignee
Nellcor Puritan Bennett
CA, US
IPC
H05B 37/02
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