AM3352: AM3352BZCZD30 thermal issue

Hello Liang Paker,

Thank you for the query.

Could you please help me understand the procedure you are following for temperature measurement.

I assume this is a custom board. Any thoughts on the cooling options available for the board.

Regards,

Sreenivasa

Hi  Kallikuppa

 Yes it is a custom board, design by ourself.

1. The board is in a IP65 Case, thermocouple is fixed on the chip.  Then put the case in temperature chamber. 

2. Set chamber to 60℃ and power on the board.

3  Chamber temperature hold 60℃  for 4hours.

4  Measure the thermocouple value.

Hello Liang Paker,

Thank you for the inputs.

There is an App note (Semiconductor and IC Package Thermal Metrics, SPRA953C) which should provide more guidance.

https://www.ti.com/lit/an/spra953c/spra953c.pdf

3 ΨJT, Junction to Top of Package

I did a quick look and see the following formula for Tj based on Tc

Given that the case temperature is approaching the maximum junction temperature I would say the device may already be out of spec.

Please verify.

Regards,

Sreenivasa

Hi  Kallikuppa

If I replace with AM3352BZCZA30(-40 to 105), it can meet spec, right?

Hello Liang Paker,

Thank you.

Please help me understand your spec: Is it operating at 60℃?

Regards,

Sreenivasa