6 Replies Latest reply on Oct 3, 2019 11:45 PM by PradiptaB_11

# S34ML01G1 Junction to Board thermal resistance

Hello,

Can you provide thermal resistance of Junction to Board for S34ML01G1?

Thanks,

• ###### 1. Re: S34ML01G1 Junction to Board thermal resistance

The full part number is S34ML04G100BHI003

• ###### 2. Re: S34ML01G1 Junction to Board thermal resistance

Hi,

We generally do not provide the Theta JB and Theta JC parameters in the datasheet. Instead we provide a parameter called Psi Jt which provides a better estimate for the thermal parameters.

Kindly refer to the app note below for more information.

The Psi Jt parameter for the part will be equal to

Psi Jt = 10.5 C/W

Thanks,

• ###### 3. Re: S34ML01G1 Junction to Board thermal resistance

So, do we assume there is no heat dissipation through board?

Joo-Han

Joo-Han Kim, Ph.D.

Senior Mechanical Engineer

Abaco Systems

T +1 256 382 8262

Email: joo.kim@abaco.com<mailto:joo.kim@abaco.com>

12090 Memorial Parkway, SW

Huntsville, AL 35803

USA

www.abaco.com<http://www.abaco.com>

• ###### 4. Re: S34ML01G1 Junction to Board thermal resistance

Hi Kim,

There will be heat dissipation through the board. You can use Theta JB = 7.3 C/W for all your calculations.

Thanks,

• ###### 5. Re: S34ML01G1 Junction to Board thermal resistance

Great! Thanks. Just my last question. What is the maximum junction temperature?

• ###### 6. Re: S34ML01G1 Junction to Board thermal resistance

Hi Kim,

The maximum operating junction temperature, can be calculated by using the below formula.

Tj = Pd*Theta Ja + Ambient Temperature

Pd is power dissipation.

Pd (max) = Vdd max * Idd max = 3.6*30 = 108mW

Using Theta Ja as 39 C/W and max ambient temperature

Tj can be calculated to be 89.212 C

Thanks,