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US 2002/0171376 A1Published application
Method for starting a discharge lamp using high energy initial pulse
AssigneeMonolithic Power Systems, Inc.
InventorsTimothy James Rust, James Copland Moyer, David Joseph Christy
Life of this patent
Estimating the term…
Abstract
The described DC to AC inverter efficiently controls the amount of electrical power used to drive a cold cathode fluorescent lamp (CCFL). Additionally, during striking of the CCFL, a higher energy initial energy pulse is used. During normal operation, a lower energy pulse is used.
Claims20
Apparatus for driving a lamp, comprising:
- (a) a network of a plurality of switches for generating an AC signal from a DC signal coupled to the network of the plurality of switches, the AC signal being generated by a portion of the network of the plurality of switches periodically opening and closing opposite to the periodic opening and closing of another portion of the network of the plurality of switches;
- (b) a tank circuit being coupled between the network of the plurality of switches and the lamp, the tank circuit filtering the AC signal delivered to the lamp;
- and
- (c) a controller for periodically opening and closing portions of the network of the plurality of switches based on a resonant frequency of the tank circuit, so that the optimal amount of electrical power is provided for driving the lamp under a range of voltages provided by the DC signal, said controller also operative to provide a higher energy pulse during striking of the lamp.
1 more element
Apparatus for driving a lamp, comprising:
- (a) a DC to AC converter for converting a DC signal to an AC signal;
- (b) a self-oscillating circuit between the DC to AC converter and the lamp, the self-oscillating filtering the AC signal delivered to the lamp;
- and
- (c) a controller for adjusting the DC to AC converter such that the frequency of the AC signal is based on a resonant frequency of the self-oscillating circuit, said controller also operative to provide a higher energy pulse during striking of the lamp than during normal operation.
1 more element
A method for driving a discharge lamp, comprising:
- (a) converting a DC signal into an AC signal;
- (b) filtering the AC signal to the discharge lamp;
- (c) oscillating the conversion of said DC signal such that the AC signal has a frequency based on a resonant frequency of a load;
- and
- (d) providing a higher energy pulse to said lamp during striking of said lamp relative to normal operation.
2 more elements
Dependencies are inferred from the claim text.