TPS63900: input Current limit protection

pragash sangaran78

Part Number: TPS63900

What is the guideline for setting input current limit for a load? Let's say the maximum/peak current draw by a Load at any time is 15mA. What is the safe current value that can be set?

over 5 years ago

0 Minqiu Xie over 5 years ago

TI__Mastermind 21565 points

Hi Pragash:

The input current is related the Vin, Vout. May you share that information with me?

And may I know the purpose that you set the current limit? Thank you!

0 pragash sangaran78 over 5 years ago in reply to Minqiu Xie

Genius 3510 points

VIN range = 4.35 - 3V (battery)

Vout is 3.3V for one regulator and 1.8V for another. We are using two TPS63900.

We set the current limit for the same purpose. It's actually invented. overcurrent protection and protect circuitry from short circuit. moreover, you have to set the current in TPS63900. that's how it works. we don't have a choice!

0 Minqiu Xie over 5 years ago in reply to pragash sangaran78

TI__Mastermind 21565 points

Hi Pragash:

The Iin_avg=Vout*Io/Vin/Efficiency. And you should consider the worst case, as max Vout, heaviest loading, and min Vin.

If just for short current protection, I'll recommend set the limitation little larger to leave more margin. And it will do help for faster transient.

0 pragash sangaran78 over 5 years ago in reply to Minqiu Xie

Genius 3510 points

could you please explain this formula?

The Iin_avg=Vout*Io/Vin/Efficiency.

0 Minqiu Xie over 5 years ago in reply to pragash sangaran78

TI__Mastermind 21565 points

Hi Pragash:

Yes, with pleasure.

This formula ignores the ripple to simplify the calculation. And:

Input power * Efficiency =Output power ==> Vin*Iin*Efficiency = Vout*Iout ==> Iin=Vout*Io/Vin/Efficiency.

Power management

Power management forum

TPS63900: input Current limit protection