Control of light intensity using pulses of a fixed duration and frequency
First Claim
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1. A processing device comprising:
- a processor configured to generate a current switch control signal supplied to a current switch and to time a start and end of each pulse within a timing cycle, wherein the current switch is configured for connection to a first power potential, a second power potential, and a light source, and including an input to receive a current switch control signal to place the switch in one of an ON state and an OFF state including a timing cycle with a series of pulses of fixed duration and fixed frequency within the timing cycle to cause current to flow from the first potential to the second potential through the light source during the ON state to cause the light source to emit light of a desired intensity over the timing cycle.
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Abstract
A method and circuit to control the intensity of lights, illumination fixtures, and displays using pulses of a fixed duration and a fixed frequency (FD/FF) is provided. In particular, the method may be used to control one more light sources. By varying the number of pulses in a control burst, the total current flowing through the light source may be precisely controlled providing greater accuracy than other methods, such as, for example, PWM or variable pulse frequency. The FD/FF technique may be used in conjunction with any number of light sources, and finds particular application in LED displays and for any type of LED illumination fixture.
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Citations
9 Claims
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1. A processing device comprising:
a processor configured to generate a current switch control signal supplied to a current switch and to time a start and end of each pulse within a timing cycle, wherein the current switch is configured for connection to a first power potential, a second power potential, and a light source, and including an input to receive a current switch control signal to place the switch in one of an ON state and an OFF state including a timing cycle with a series of pulses of fixed duration and fixed frequency within the timing cycle to cause current to flow from the first potential to the second potential through the light source during the ON state to cause the light source to emit light of a desired intensity over the timing cycle. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
Specification