TempSense data is so weird..

[rlaxortn]

i am using s32k314, s32ds 3.6.1 Version. 

i make a source code for reading MCU TempSense. 

when i get data from MCU TempSense data, data is so weird..

before i use Adc_Sar_Ip_TempSenseGetTemp function, i use Adc_Sar_Ip_TempSenseEnable(1U). 

reason parameter 1 is i use make TempSense adc channel in adc1 by adc config.

1. why data is so weird..?

2. do i have to do something?

3. when you see first pic, adc resolution is 14. so tempSens resolution is 14bit?????

thanks to help.

[Senlent]

Hi@rlaxortn

Your ADC reference voltage is 3.2V?

[rlaxortn]

@Senlent 

1. How can I know the supply voltage of Tempsense? Isn't the operating power of MCU the supply voltage of TEMPSense? or dose TempSense have other pin for getting Voltage like adc Channel?

2. because MCU Supply voltage is 3.3V. so i set TempSense Supply Voltage is 50(0x32)-> 3.2V.

3. anyway i test Tempsense Supply voltage, 0x50(5.0V), 0x15(1.5V), 0x33(3.3v).

when i set 0x50.

(TemperatureRaw is Integer value, mcuTempData is float for print)

ex) 2205 -> 0x89D

when i set 0x33(3.3V)

(TemperatureRaw is Integer value, mcuTempData is float for print)

ex) 2537->0x9e9

when i set 0x15(1.5V)

ex) 5515->0x158B

[Senlent]

Hi@rlaxortn

From the data you provided, your ADC sampling results fluctuate greatly. This should be due to some problems in your ADC sampling configuration.
1. Provide your project and I will help you check the ADC settings
2. Please confirm the ADC reference voltage on your current hardware and test the actual voltage of VREFH.

[rlaxortn]

@Senlent 

1. it is difficult i give to you source code. but i can give adc configure by image capture. is it okay?

2. MCU VREFH is 5.0v, and VREFL is 0V. 

[rlaxortn]

@Senlent 

1. sorry, that is my mistake. VREF is 5.0V absolutely. so i already change value 0x50. 

but result is same. 

2. i gonna set larger than current value. 

But I don't think that's a solution. i can catch the data shaking, but the values are weird.

you know previous pics, temperature is over 150 at least.

[Senlent]

Hi@rlaxortn

What's your RTD version is? 

[rlaxortn]

@Senlent 

i check hardware by hardware engineer. so i knew Data is unstable. 

although i supply vref voltage is 5.0V,  vref is unstable (4.1V~ 5.8V).

RTD Version is 4.0.0.

thanks to help.

[Senlent · Accepted solution]

Hi@rlaxortn

In your last answer, you said "because MCU Supply voltage is 3.3V". Now you say "MCU VREFH is 5.0V". Are you serious?

In your configuration , the TempSense Voltage Supply is 0x53, that is 5.3V

the Adc Voltage Reference is 53->0x35->3.5V

We've been talking for so long and you keep making the same mistakes。

If your VREFH is 5V, then you should set both values to 0x50.

Secondly, to improve stability, you can set the following parameters to a larger value and test again.