Low-visual noise, jitterized pulse width modulation brightness control circuit
AssigneeBeyond Innovation Technology Co., Ltd.
InventorsAndre Yu, Jeffrey Chang, Bill Huang
Life of this patent
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Abstract
A low visual noise, jitterized pulse width modulation brightness control circuit is provided. The circuit uses a brightness control signal generating unit to receive a brightness adjusting signal and to generate a brightness control signal in response to the brightness adjusting signal. The brightness control pulse signal has a duty cycle or frequency varying in a predetermined range. An inverter coupled to the brightness control signal generating unit drives the fluorescent lamp in response to the brightness control pulse signal to reduce the visual interference due to the adjustment of the current beam density.
Claims6
A pulse width modulation brightness control circuit, for determining a brightness of a lighting device comprising:
- a brightness control signal generating unit, receiving a brightness adjusting signal and generating a brightness control signal in response to said brightness adjusting signal, the brightness control signal is a pulse signal having a duty cycle which is varying with time in a predetermined range when the brightness of the lamp is determined;
- and
- a circuit for delivering a power to the lighting device, wherein the power is controlled based on the brightness control signal.
A pulse width modulation brightness control circuit, for determining a brightness of a lighting device comprising:
- a brightness control signal generating unit, receiving a brightness adjusting signal and generating a brightness control signal in response to said brightness adjusting signal, the brightness control signal is a pulse signal having an frequency which is varying with time in a predetermined range;
- and
- a circuit for delivering a power to the lighting device, wherein the power is controlled based on the brightness control signal.
Dependencies are inferred from the claim text.