[FAQ] LM3630A: Flicker with 80kHz PWM signal

 Hello Expert,

I have questions for LM3630A.
My customer is evaluating this device but they are facing flicker issue with this.
At this moment, they haven't figured out the root cause of this issue and it is just possibility that this issue is from LM3630A.
So I'd like to know about detailed behavior of PWM operation and get your opinion for their use case.

They are using this device under following condition.
PWM frequency: 80kHz
PWM Duty: 2%~100%
Register[0x00]:0x17
Register[0x01]:0x1B
Register[0x02]:0x20
Register[0x03]:0xFF
Register[0x05]:0x15
Register[0x50]:0x03

Question 1.
I think this device convert duty ratio to digital cord at sample period block.
After then this value through moving average filter at LPF block and it pass to the hysteresis and Min block.
Is this understanding correct?

Question 2.
Is there any concern that may cause flicker on current customer use case?

Question 3.
Is there example of use case that cause flicker even if customer use this device within recommended condition?

I'm looking forward to hearing back from you.


Best regards,
Kazuki Kuramochi