reference voltage in STM32H743 for Calibration values TSCAL2 & TSCAL1 ?

[Saranraj]

What is the reference voltage did ST set in STM743 micro controller for temperature sensor for acquiring the Calibrated value TSCAL2 & TSCAL1 for 130*C and 30*C. Since during factory set How do ST Know What external voltage is going to come from design side ?

For Example If you set reference voltage 1.2V for 130*c then How do i scale it that if i give 2.5V external voltage for Vref ? Then calibrated value i am getting from internal is different from what i am expecting so it will throw error in calculation ? How do i know the information about factory set Ref voltage for TSCAL2 and TSCAL1 for maximum and minimum temperature ?

Is there any application note for calculating the temperature as per the reference voltage to get to know the internal calibrated value for TSCAL2 & TSCAL1 ?

[Saranraj]

Hi TDK,

 Thank You for your reply. Yes I agree with you. But in my design i am giving 2.5V externally to the Vref pin of the IC. SO will it give wrong values for calculating the temperature since internally temp sensor  it is set(Calibrated) for 3.3V ?

How do i map it for 3.3V values  to 2.5V  ? 

Regards

Saranraj

[Saranraj]

Hi TDK,

 Thank You for your reply. How do i know the revision number if my system is closed and what if its production board ???

[TDK]

I've given you two ways of finding it out above. If you don't want to use those, perhaps guess V (most likely) and if your temperature results are wrong, you have the other revision. Not sure how it being a production board is relevant or what "closed" means here. If it's "closed" in the sense that you can't see it, access it, or upload any code, then perhaps telepathy can help?

To map an ADC reading taken with VREF+ of 2.5 as if it were taken with a VREF+ of 3.3, multiply the value obtained by 2.5 / 3.3.

[Saranraj]

Hi TDK,

  I Got it. I agree with your points. I can map the value to 2.5V. But Both Rev 7 and Rev10 ST uC Datasheet shows different temperature in Rev V ?

In Rev 10

In Rev 7 DS

So While doing calculation which temperature should i consider for TSCAL2 when using below formula whether is it 110* or 130*C ? Please Calrify

And Addition to this One more query ?

How to read the internal temperature sensor output value converted by ADC (TSDATA) ? ?

Thanks 

Saranraj

[Saranraj]

Could you please tell me the memory address where ADC converted data(TSDATA) is Stored ?? How to read the ADC Converted data ? I have closed system so i am reading all the data through RS485 .

Regards

Saranraj

[TDK]

> Please Calrify

Datasheets are revised to correct information. Use the latest one.