LIGHT EMITTING DIODE DRIVING APPARATUS AND LIGHT EMITTING DIODE DRIVING METHOD
First Claim
1. A light emitting diode driving apparatus configured to drive a light emitting diode load, the driving apparatus comprising:
- a driving circuit, coupled to the light emitting diode load, the driving circuit providing a driving voltage to one terminal of the light emitting diode load according to a pulse-width modulation driving signal;
a feedback circuit, coupled to the other terminal of the light emitting diode load, the feedback circuit generating a feedback voltage according to a voltage on the other terminal of the light emitting diode load; and
a control chip, coupled to the driving circuit and the feedback circuit, the control chip generating the pulse-width modulation driving signal and adjusting a duty cycle of the pulse-width modulation driving signal in response to the feedback voltage,wherein if the control chip determines that the control chip continues outputting the pulse-width modulation driving signal with a threshold duty cycle for a period of time, and the period of time exceeds a preset period of time, the control chip determines a current leakage phenomenon occurs on the light emitting diode load and stops generating the pulse-width modulation driving signal.
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Accused Products
Abstract
A light emitting diode (LED) driving apparatus and an LED driving method suitable for driving an LED load are provided. The LED driving apparatus includes a driving circuit, a feedback circuit, and a control chip. The driving circuit provides a driving voltage to one terminal of the LED load according to a pulse-width modulation (PWM) driving signal. The feedback circuit generates a feedback voltage according to a voltage on the other terminal of the LED load. The control chip is configured to generate the PWM driving signal and adjust the duty cycle of the PWM driving signal in response to the feedback voltage. If the control chip determines the PWM driving signal with a threshold duty cycle continues being output over a preset period of time, the control chip determines that the current leakage phenomenon occurs on the LED load and stops generating the PWM driving signal.
8 Citations
17 Claims
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1. A light emitting diode driving apparatus configured to drive a light emitting diode load, the driving apparatus comprising:
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a driving circuit, coupled to the light emitting diode load, the driving circuit providing a driving voltage to one terminal of the light emitting diode load according to a pulse-width modulation driving signal; a feedback circuit, coupled to the other terminal of the light emitting diode load, the feedback circuit generating a feedback voltage according to a voltage on the other terminal of the light emitting diode load; and a control chip, coupled to the driving circuit and the feedback circuit, the control chip generating the pulse-width modulation driving signal and adjusting a duty cycle of the pulse-width modulation driving signal in response to the feedback voltage, wherein if the control chip determines that the control chip continues outputting the pulse-width modulation driving signal with a threshold duty cycle for a period of time, and the period of time exceeds a preset period of time, the control chip determines a current leakage phenomenon occurs on the light emitting diode load and stops generating the pulse-width modulation driving signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A light emitting diode driving method with a current leakage protection mechanism, the light emitting diode driving method being adapted to a light emitting diode load and comprising:
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generating a pulse-width modulation driving signal; providing a driving voltage to one terminal of the light emitting diode load according to the pulse-width modulation driving signal; generating a feedback voltage according to a voltage on the other terminal of the light emitting diode load; adjusting a duty cycle of the pulse-width modulation driving signal in response to the feedback voltage; and determining whether a period of time during which the pulse-width modulation driving signal with a threshold duty cycle continues being output exceeds a preset period of time, if yes, determining that the current leakage phenomenon occurs on the light emitting diode load and stopping generating the pulse-width modulation driving signal. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17)
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Specification