UCC27531: power dissipation characteristics of Gate drive IC

Mallikharjuna Reddy

Prodigy 50 points

Part Number: UCC27531

Request you to please provide power dissipation derating characteristics.

over 6 years ago

0 Jeffrey Mueller over 6 years ago

TI__Genius 12990 points

Hi Mallikharjuna,

Welcome to e2e! Thanks for asking about UCC27531. The power derating factor can be determined by using Rja. Check out section 1 of this app note (www.ti.com/.../spra953c.pdf) that explains how to find your own effective Rja in your own system.

As a ballpark, max Power dissipation at room temp for SOIC package can be estimated by Pmax = (Tjmax-Ta)/Rja = (150 - 25)/129.9 = 962mW. This curve derates at a factor equal to the slope of the curve when varying Ta. This slope ends up being about 7.7mW/C.

Does this make sense?
Thanks,

0 Mallikharjuna Reddy over 6 years ago in reply to Jeffrey Mueller

Prodigy 50 points

In Datasheet, Rja is showing as 178.3°C/W. Can I consider it as (150-25)/178.3 = 701mW. the derating factor as 5.6mW/°C.

0 Jeffrey Mueller over 6 years ago in reply to Mallikharjuna Reddy

TI__Genius 12990 points

Hi Mallikharjina,

You can consider this derating factor for the DBV package to be 5.6mW/°C above room temp.

The derating factor is lower because of the lower power rating when compared to the SOIC package.

please let me know if you have any more questions!

Thanks,

Power management

Power management forum

UCC27531: power dissipation characteristics of Gate drive IC