LM73606-Q1: Any concerns if enable is earlier than Vin

user4979989

Intellectual 2800 points

Part Number: LM73606-Q1
Other Parts Discussed in Thread: LM73606

Hi team,

Would you please advise if there is any concerns in sequence if enable is earlier than Vin?

Or this part doesn't have power up/down sequence limitation?

Thank you.

Regards,

Allen

over 5 years ago

0 Samuel Jaffe over 5 years ago

TI__Mastermind 25590 points

Allen,

We do not recommend applying a voltage to EN before VIN. Devices typically have ESD diodes from each pin to GND and to VIN so applying a voltage to EN before VIN may cause current to flow through that ESD diode (which is not rated for continuous current).

-Sam

0 Eddie Chen1 over 5 years ago in reply to Samuel Jaffe

Prodigy 150 points

Hi Sam,

If EN signal add RC delay, can it avoid current flow through the ESD diode? (or not recommend this way)

0 Eddie Chen1 over 5 years ago in reply to Samuel Jaffe

Prodigy 150 points

Hi Sam,

If PR90=10k to limit EN input current, does still exist any concerns of "EN signal earlier than Vin"?

0 Samuel Jaffe over 5 years ago in reply to Eddie Chen1

TI__Mastermind 25590 points

Eddie,

You need to check if the LM73606 input voltage rises faster than the low-passed EN signal so that it does not violate the absolute maximum spec of the EN pin which is VIN + 0.3V. Limiting the current into the EN pin would be a more reasonable solution but still not recommended. ESD diodes are not meant for continuous current.

-Sam and Jerry

Power management

Power management forum

LM73606-Q1: Any concerns if enable is earlier than Vin