LP8863-Q1: PWM input

Koji Hayashi92

Part Number: LP8863-Q1

Hi TI-team

Can I use Hybrid dimming when I have PWM input?

When using PWM input, does it mean that the LED turns on and off with the duty cycle of PWM in put for the current set in ISET?

Best Regards,

Koji Hayashi

over 3 years ago

0 Charles-Chen over 3 years ago

TI__Genius 11836 points

You could use Hybrid dimming when you have PWM input.

Correct for your second question.

0 Charles-Chen over 3 years ago

TI__Genius 11836 points

You could use Hybrid dimming when you have PWM input.

Correct for your second question.

0 Koji Hayashi92 over 3 years ago in reply to Charles-Chen

Mastermind 6970 points

Hi Charles-san

Thank you for quick response.

In the case of hybrid dimming, PWM input: 200Hz, LED PWM: 152Hz, if I want to brighten the LED by 1 bit, should I set the duty cycle of the PWM input at 0.016% since 0001h is approximately 803ns?
200Hz＝5ms
803ns/5ms*100=0.016%

0 Koji Hayashi92 over 3 years ago in reply to Koji Hayashi92

Mastermind 6970 points

Sorry, I misunderstood.

803ns/5ms*100=0.016%

803ns/6.58ms(1/152Hz)*100=0.000122%

Do you mean the brightness of 0001h when the duty cycle of PWM input is 0.000122%?

+1 Charles-Chen over 3 years ago in reply to Koji Hayashi92

TI__Genius 11836 points

Hi Koji-san,

If you want to increase 1 bit output duty cycle, the PWM duty cycle increase step is 1/65536*1/200.

0 Koji Hayashi92 over 3 years ago in reply to Charles-Chen

Mastermind 6970 points

Hi Charles-san

Thank you for response.

I understand.

I understood that the LED is divided into 65536 by the Duty of the PWM input and dimmed.

If it is 50%, it will be dimmed as 32768/65536:8000h.

Other questions have come up, so I'll ask them in a separate thread.

Best Regards,

Koji Hayashi

Power management

Power management forum

LP8863-Q1: PWM input