Hello Basavaraj,
TMP101 or any of the local temp sensors will be able to measure the temperature of the PCB exactly at its location (not 1-2 inches away). This being said I would like to clarify that it all depends upon the thermal profile of the PCB itself. If your PCB has metal traces and heat is distributed such that there is not much thermal gradient from one end to the other end of PCB then the answer is - yes, TMP101 will measure the entire 5 inch PCB area. But, I don't think this is the case since heat and we need to find you a suitable solution.
I would suggest going for a remote junction temp sensing but since we are dealing with ECU I would rather obtain more clarity on your application and specifications.
Please send me an email to: abhishekmuppiri@ti.com with your contact information and we will setup a quick phone call and chat about your needs. Hopefully, we can quickly come up with a solution.
Best Regards,
Abhi Muppiri
Applications Engineer
MHR- Sensing Products
Texas Instruments
------------------------------------------------------------------------------------------------------------------------------------------------
Search for answers, Ask a question, click Verify when complete, In the process, Help others, Learn more...