LM5050-1: LM5050-1 start up issue

Red Yen

Part Number: LM5050-1

Hi Support team

I would like to re-start this inquiry since the discussion has been locked two month ago,

pls refer following for the schematic and Waveform, the part marked in the red circle is affected by the ORing FET. the input and output caps was included,

the output is E-load so, there is no hung cap after ORing FET,

How can I improve this problem? Thank you,

Please refer to the following waveforms (before ORing FET, ORing FET and LM5050-1 gate)

over 6 years ago

0 Karikalan Selvaraj over 6 years ago

TI__Genius 16305 points

Hello Red,

Are you referring to the jump in voltage during startup on "Front of ORing FET" waveform?

Regards,
Kari.

0 Red Yen over 6 years ago in reply to Karikalan Selvaraj

TI__Expert 4360 points

Hi Kari

i have no idea for your question, you are talking about the "current" during start up on "Front of ORing FET" or "voltage"

the output E-load is setting up at 25V/1.6A

0 Karikalan Selvaraj over 6 years ago in reply to Red Yen

TI__Genius 16305 points

I am referring to the voltage waveform of channel 1 in the waveform attached by you. It is labelled as "Front of ORing FET"

Is your concern or the issue about the jump in the voltage seen during startup?

Regards,

Kari.

0 Red Yen over 6 years ago in reply to Karikalan Selvaraj

TI__Expert 4360 points

Hi Kari,

yes, Front of ORING FET is my concern, why the front of ORING would not smoothly like the behind of ORING,

is this normal behavior?

0 Karikalan Selvaraj over 6 years ago in reply to Red Yen

TI__Genius 16305 points

This is a normal behavior as the MOSFET turns ON, drop across the body diode of the MOSFET is not seen ( now after turn on ).

Regards,

Kari.

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LM5050-1: LM5050-1 start up issue