Hi Yaakov,

Have no idea till now. I found ATmega32 by Atmel - it has 10 bits ADC and is 1.2 mm thick. Would it be a solution for my project? Only the temperature range is up to 85C... I would prefer smth up to 150C

Now it seems the temperature range is up to 300°C. Is that an internal temperature? Can you use thermal imaging?

A big hurdle will be getting that thing to work at those temperatures. I came across this review from Analog: https://www.analog.com/en/analog-di...rature-electronic-pose-design-challenges.html The oil industry is one of the drivers. Apparently, it is doable, but it sounds expensive. Can you consider alternatives?

 

No battery will survive the conditions you say you must deal with. If you are going to use a rotary contact, you are better off using that contact to connect to the sensor than trying to put the device inside.

Consider some other what to probe the place of interest. Consider ways to get the sensor signal outside the DUT to eliminate the need for tiny size and power.

Consider that you might be doing this completely wrong since what you propose seems practically impossible and that has nothing at all to do with the choice of ADC.

 

Hi Temp offerings -

https://www.digikey.com/en/articles...n-extended--and-high-temperature-applications


Regards, Dana.

 

Hello everybody, I have no experience with microcontrollers. My project is temperature sensor (thermo couple) which generates some mili volts, amplifying them with Op amp into 3-4 Volts and after that I need microcontroller with ADC (10 bits will be enough). Microcontroller should store the data from measuring into external EEPROM or flash memory for example. The working temperature should be something like 150 C and the size of the microcontroller should be as small as possible. Could you suggest me microcontroller for that purpose. Thanks!

Can you make a list of the High Temperature Microcontrollers that you have already found and list the reason why they are unacceptable?

PIC Microcontroller, up to +150°C
https://www.microchip.com/design-centers/high-temperature

 

Correct me if I am wrong, I think the OP means the oil bath may reach 150C, while the measurement points can go to 300C?
Is this the right interpretation?

 

If that is the correct interpretation, then the question becomes, if the electronics can be at 85° to 150° while the clutch will be up to 300°, why can't the electronics be moved entirely outside the oil bath?

In any event, it looks like 125° is easily attained, and 150° can be attained with ordinary "high temperature" parts. On a search, I found a primary lithium battery rated for 200°C. That is also related to deep bore oil production.

 

If that is the correct interpretation, then the question becomes, if the electronics can be at 85° to 150° while the clutch will be up to 300°, why can't the electronics be moved entirely outside the oil bath?

In any event, it looks like 125° is easily attained, and 150° can be attained with ordinary "high temperature" parts. On a search, I found a primary lithium battery rated for 200°C. That is also related to deep bore oil production.

Is that cell ≥2.5mm? Because that's one of the constraints. I don't think it is practical to try to build something that will work in place. I think if it is done, it will have to be done by connecting to the sensor from outside. I could be wrong, but it seems impractical.