LP38692: Dropout voltage at 0.5V

Jeff Xie

Intellectual 1780 points

Part Number: LP38692

Hi expert,

Customer has two questions:

1. What is the Dropout voltage (Vdo) (Typ) (mV) 250 test condition?

2. When Input id 5.5V, output voltage is 5V, and current is 0.5A, what is the typical and max dropout voltage?

over 5 years ago

0 JCHK over 5 years ago

TI__Mastermind 48560 points

Hi Jeff,

The best way to describe this to the customer is to look at the maximum VDO at 5V which is 800mV and 1A as shown below:

This says the effective RDSON for 5VOUT is 0.8Ohms. So worst case for 500mA would be 400mV.

Please let me know if I misunderstood your question.

0 Jeff Xie over 5 years ago in reply to JCHK

TI__Intellectual 1780 points

John,

Do we have dropout voltage v.s. output current graph at 5V output?

As worse case of 500mA is 400mV dropout voltage, what is typical value?

0 JCHK over 5 years ago in reply to Jeff Xie

TI__Mastermind 48560 points

Hi Jeff,

I do not have a graph for 5VOUT, but the analysis above works for the typical value. Meaning the typical VDO at 450mV at 1A is an effective RDSON of 450mOhms. So at 500mA, this would be a typical VDO of 225mV.

I hope this helps.

The TI E2E™ design support forums will undergo maintenance from July 11 to July 13. If you need design support during this time, open a new support request with our customer support center.

Power management

Power management forum

LP38692: Dropout voltage at 0.5V