LP8866-Q1: LED configuration mismatch

Hirotsugu Kobayashi

Part Number: LP8866-Q1

Hi, team.

If LED_SET is set to 6Ch and an unused OUT6 terminal is connected to GND,

does the operation stop due to LED short?

Or does the OUT6 pin automatically exclude and operate?

Best Regards,

0 Charles-Chen over 4 years ago

Hi Kobayashi-san,

LED short to ground will be detected. Device goes to Fault Recovery and then attempts to restart 100 ms after fault occurs.

0 Hirotsugu Kobayashi over 4 years ago in reply to Charles-Chen

Hi, Charles-san,

Thank you.

I have additional questions.

How do you use the LEDx_SHORT_DISABLE register?

Best Regards,

0 Charles-Chen over 4 years ago in reply to Hirotsugu Kobayashi

Hi Kobayashi-san,

It is just used to disable the corresponding short fault. The fault action will keep unchanged.

0 Hirotsugu Kobayashi over 4 years ago in reply to Charles-Chen

Hi Charles-san,

If LED6_SHORT_DISABLE is disabled, does it work even if OUT6 is shorted to GND?

Best Regards,

0 Charles-Chen over 4 years ago in reply to Hirotsugu Kobayashi

Hi Kobayashi-san,

Yes.

0 Hirotsugu Kobayashi over 4 years ago in reply to Charles-Chen

Hi Charles-san,

In our system, the number of LED strings has several patterns.

Since it is troublesome to change the resistance of LED_SET,

is it possible to evaluate by shorting unused OUTx to GND and setting the LED_SHORT_DISABLE register?

Best Regards,

0 Charles-Chen over 4 years ago in reply to Hirotsugu Kobayashi

Hi Kobayashi-san,

You need to configure the different LED_SET resistor for different patterns. The device will restart when the LED short to GND happens.

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