LM5116: LM5116 start issure

user3768230

Part Number: LM5116

Hi support!

our project PMU is based on LM5116. The input voltage is 50V, and the output voltage is 24V. The output voltage is used for driver 2 motors ,and per motor power is 75W.

But when driver the motor, the start time up to 1.36S, the time is too long for our application. We do a comparative test that the DC power supplys the power energy for motors,and the start time is 0.2S.

We need 24V, and want to decrease the motor start time. So what is different for the test? And what can we do to decrease the start time?

Thank you !

over 8 years ago

0 Arief Hernadi over 8 years ago

TI__Mastermind 23845 points

Hi,

We have received your question, in the meantime do you have schematic to share?

Thanks
-Arief

0 user3768230 over 8 years ago in reply to Arief Hernadi

Prodigy 50 points

POWER_LM5116_24V.pdf

0 Arief Hernadi over 8 years ago in reply to user3768230

TI__Mastermind 23845 points

Hi,

It seems that you have a lot of output capacitor. Have you checked how much current during soft-start that the converter source?
It could be that the converter is hitting a current limit during soft-start. Do you have some scope picture to share about the inductor waveform and the switch node during soft-start?

Thanks
-Arief

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LM5116: LM5116 start issure