§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
EP0507399A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Circuit arrangement

Assignee: Koninklijke Philips NV
•
Filing: 1992-03-30
•
Granted: —
•
Expires: 2012-03-30
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The invention relates to a circuit arrangement for operating a discharge lamp (L) with a substantially constant power PL by means of a switch mode power supply with variable input current Io and provided with periodically switching switching means (10) for controlling the variable input current by means of a drive signal. The drive signal generated in a drive circuit (V) is formed from a signal S1 which is proportional on the one hand to the input current and on the other hand to the lamp voltage VL and a reference signal. The circuit arrangement comprises means (IV) for generating signal S1. The power PL by good approximation thereby satisfies the relation PL = VbIo - K2/VL in which Vb = supply source voltage VL = lamp voltage K2 = proportionality constant. <IMAGE>

Inventors

  • 👤 Anton Cornelis Blom

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-29 15:35
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/282; G; G05; G05F; G05F1/00; G05F1/10; H05B41/36; H05B41/38; H05B41/39; H05B41/392; Y; Y02; Y02B; Y02B20/00

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 100 words
A circuit arrangement for operating a discharge lamp at a substantially constant power by means of a switch mode power supply having a variable input current and provided with switching means which switch periodically for controlling the input current by means of a drive signal generated in a drive circuit and formed from a signal S1 which is proportional to the input current and a reference signal, which circuit arrangement comprises means for generating the signal S1, characterized in that it comprises means by which the signal S1 is also given a dependence on the lamp voltage V L .
Claim 2
Dependent Claim 37 words
A circuit arrangement as claimed in Claim 1, characterized in that the means for generating the signal S1 comprise an electric circuit for summation of signal voltages which represent the input current and the lamp voltage, respectively.
Claim 3
Dependent Claim 29 words
A circuit arrangement as claimed in Claim 1 or 2, characterized in that the electric circuit also serves for summation of a signal voltage representing a supply source voltage.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag