LP8869-Q1: Maximum dimming ratio

Shinji Tsuji

Genius 14099 points

Part Number: LP8869-Q1
Other Parts Discussed in Thread: LP8863-Q1

Hi team,

I would like to achieve dimming ratio of 7250:1 @200Hz PWM dimming using LP8869-Q1.

Is this level of dimming possible?

In the datasheet, it is described as high as 10,000 : 1, but at 100Hz.

regards,

0 Frank Qiu over 5 years ago

I think the dimming ratio in 200Hz PWM is 5000:1.

Could you tell me your application, I think LP8863-q1 can satisfy your need.

0 Shinji Tsuji over 5 years ago in reply to Frank Qiu

Hi,

Application is automotive display back light.

What limit the dimming ratio technically?

I only need 70mA/3ch 8 in series, so LP8863-Q1 might be too much for me.

What is the difference in dimming technology which enables >7250 : 1?

regards,

0 Frank Qiu over 5 years ago in reply to Shinji Tsuji

The limit is the min on-time of the inner mos.

0 Shinji Tsuji over 5 years ago in reply to Frank Qiu

Thank you.

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