LM46002: LM46002 damaged at the time of a start of a power supply.

user4913799

Prodigy 30 points

Part Number: LM46002

Input voltage +48V and output voltage +24.
IC is damaged at the time of a start of a power supply.
Is there a measure?

over 6 years ago

0 Katelyn Wiggenhorn over 6 years ago

TI__Genius 11040 points

Hi,

How are you connecting VIN? Is this a 'hot plug'?

Thank you,
Katelyn

0 user4913799 over 6 years ago in reply to Katelyn Wiggenhorn

Prodigy 30 points

HI , Katelyn

Yes, Vin (+48V) is a 'hot plug'.

After voltage supply, control on was done in EN. It was damaged as expected.

0 Katelyn Wiggenhorn over 6 years ago in reply to user4913799

TI__Genius 11040 points

Hello,

When you 'hot plug' an input there will be ringing on the input due to the cables from the input power supply to the power supply. For a 48V input I would expect this ringing could be above 60V, and will cause catastrophic damage to the device.

Can you start up by turning on the power supply rather than a hot plug of the cable?

Best Regards,
Katelyn

0 user4913799 over 6 years ago in reply to Katelyn Wiggenhorn

Prodigy 30 points

Hi ,Katelyn

Over voltage by ESR of ceramiccondenser of input was understood.
It was settled by adding TVS to the input.

Thank you!
Hiroshi.

Power management

Power management forum

LM46002: LM46002 damaged at the time of a start of a power supply.