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US 12,223,884 B2Granted
LED driving circuit and its driving method
AssigneeLx Semicon Co., Ltd.
InventorsSang Suk Kim, Jang Su Kim, Ji Hwan Kim, Jong Min Lee, Kyeong Rok Lee
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Abstract
An LED driving circuit adjusts a PWM driving frequency in light emitting diode driving, and changes a PWM frequency of an LED driving circuit in response to a frequency of a PWM clock signal delivered externally or internally.
Claims20
An LED driving circuit comprising:
- a current channel electrically connected to a light emitting diode and configured to deliver driving current of the light emitting diode;
- a dimming control circuit configured to control the driving current of the light emitting diode according to a duty ratio of a pulse width modulation (PWM) driving control signal;
- and
- a register configured to store the indicator of a multiplier frequency corresponding to the PWM driving control signal,
- wherein a frequency of the PWM driving control signal is determined based on a reference clock signal and the multiplier frequency.
2 more elements
An LED driving circuit comprising:
- a current channel electrically connected to a light emitting diode and configured to deliver driving current of the light emitting diode;
- and
- a dimming control circuit configured to control the driving current of the light emitting diode according to a duty ratio of a pulse width modulation (PWM) driving control signal,
- wherein the dimming control circuit changes a frequency of the driving current in response to the number of clocks of a reference clock signal delivered externally or internally.
1 more element
An LED driving device comprising:
- a micro controller unit generating an LED driving control signal for controlling an operation of a light emitting diode connected to a plurality of current channels and delivering light;
- and
- an LED driving circuit generating a pulse width modulation (PWM) driving control signal based on the LED driving control signal and controlling an operation timing of driving current of the light emitting diode,
- wherein the LED driving circuit changes the operation timing of the light emitting diode every frame.
1 more element
Dependencies are inferred from the claim text.