LP8867Q1EVM: Lowest Vin when SW = 2.1MHz

Roy Chou1

Part Number: LP8867Q1EVM

Team,

I tried to use LP8867Q1EVM in 2.1MHz Fsw. But when Vin = 7V,(Vout=24V,Iout=0.4A) the IC will shut down. Is this make sense? How could we fix this issue?

We think the efficiency is bad so that cause Iin is large to detect the current limit.

Roy

over 3 years ago

0 Charles-Chen over 3 years ago

TI__Genius 11836 points

Hi Roy,

Actually, we have tested efficiency for 8LED with Vin=6V. The output current can achieve 0.47A. The efficiency is around 75% @ Vin=6V, 8LED, Iout=0.4 A. I suggest to use current probe to check the inductor current for your condition.

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

TI__Genius 11836 points

Hi Roy,

Do you have any more questions?

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

TI__Genius 11836 points

Hi Roy,

Feel free to update the feedback from your side.

0 Roy Chou1 over 3 years ago in reply to Charles-Chen

TI__Genius 11665 points

Hi Charles,

I have applied the EVM board but it have not arrived.

I will let you know if I have any question when testing EVM.

Roy

Power management

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LP8867Q1EVM: Lowest Vin when SW = 2.1MHz