TPS62801: Input current is at high frequency for TPS62801YKAR

Sajin M

Part Number: TPS62801

Hi E2E team,

I am looking for a design which will convert 2.85V supply to 1.2V having a maximum current of 0.5 A at least footprint size. And I got one design of TPS62801YKAR. But the input current is very fluctuating, will it cause any issue for the power supply module? I am attaching the design report with this please check it.

WBDesign328.pdf

over 6 years ago

0 Chris Glaser over 6 years ago

TI__Guru**** 150710 points

Hi Sajin,

Yes, TPS62801 is the smallest device for your specs.

What is the input impedance given for the Vin component? It looks like it is somewhat high. This is usually not an issue in a real system.

0 Sajin M over 6 years ago in reply to Chris Glaser

Intellectual 360 points

Dear Chris,

Thank you for your replay. Actually, I didn't know how to set the input impedance of the circuit in the webench. Can you help me to solve that?

Sajin M
Nimoplanet

0 Sajin M over 6 years ago in reply to Chris Glaser

Intellectual 360 points

How much current will take from the 2.85 V voltage source for 500 mA output current? So that I can design the 2.85V voltage supply at that rating.

0 Chris Glaser over 6 years ago in reply to Sajin M

TI__Guru**** 150710 points

Hi Sajin,

Power is always conserved. So, we can get the efficiency from figure 15 as 87% at your 500 mA load. This then becomes about 242 mA of DC input current at 2.85Vin.

0 Sajin M over 6 years ago in reply to Chris Glaser

Intellectual 360 points

Dear Chris Glaser,

Thank you for your replay. So I can go with a power rating of 250 mA for 2.85V rail, right?

0 Chris Glaser over 6 years ago in reply to Sajin M

TI__Guru**** 150710 points

Yes, 250 mA is a minimal DC rating of the 2.85V supply.

The current might go higher for a number of reasons (different efficiency, transients, etc.), so be sure and design your system with margin.

0 Sajin M over 6 years ago in reply to Chris Glaser

Intellectual 360 points

Thank you Chris

Power management

Power management forum

TPS62801: Input current is at high frequency for TPS62801YKAR