LP8556: Vboot observe 2 steps

Hardy Xue

Part Number: LP8556

Hi Team,

My customer use our LP8556SQX-E09/NOPB LED driver and we found there that Vboot ramp up with 2 steps as below waveform. Also, customer's register table as below.

We don't change Vboot setting 0xA6[5:0] but I have no idea why Vboot waveform is not linear.

Could you please help to comments this phenomenon? Thanks.

Best regards,

Hardy

over 3 years ago

0 Hardy Xue over 3 years ago

TI__Expert 3600 points

Hi team,

Could someone please help to comment this question? Thanks.

Best regards,

Hardy

0 Mason Wang over 3 years ago in reply to Hardy Xue

TI__Genius 9630 points

hello Hardy

Can I ask about the input and output condition and also the bright mode, setting in 01h

0 Hardy Xue over 3 years ago in reply to Mason Wang

TI__Expert 3600 points

Hi Mason,

Vin = 9V-13.28V

Vout = 31.35V/ Max:0.112A

01H setting is default.

Best regards,

Hardy

0 Mason Wang over 3 years ago in reply to Hardy Xue

TI__Genius 9630 points

hello Hardy

Sorry for the late reply. Is it available to also provide the waveforms of LED current, switching voltage and headroom voltage (voltage at LEDx pin)?

thanks

Mason

Power management

Power management forum

LP8556: Vboot observe 2 steps