LP8863-Q1: About PWM Dimming

GARAM AN

Intellectual 1990 points

Part Number: LP8863-Q1

Hi all,

I know that PWM dimming is controlling with duty cycle, so I think it is not related with current and voltage.

Can input current and forward voltage can be changed depending on the PWM Dimming percentage?

Thank you

over 5 years ago

0 Frank Qiu over 5 years ago

TI__Genius 15776 points

We are OoO today and will replay you later

0 Charles-Chen over 5 years ago in reply to Frank Qiu

TI__Genius 11836 points

Hi Garam,

The duty cycle of PWM will control the brightness of LED, which means the PWM dimming. The training video provide in my signature will be very helpful for you to understand the basic concepts of LED dimming methods. Feel free to ask any questions after you have watched them.

0 GARAM AN over 5 years ago in reply to Charles-Chen

TI__Intellectual 1990 points

Thank you Charles, I already watched this.

I tested and could find that output current and input current is changed depending on the PWM duty cycle.

How does it related?

Thank you

0 Charles-Chen over 5 years ago in reply to GARAM AN

TI__Genius 11836 points

Hi GARAM,

PWM duty cycle is related to the output current directly. And the input power * efficiency = output power. So the change of output current will also cause the change of input current.

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LP8863-Q1: About PWM Dimming