STM32WL Maximum storage temperature

[Terry Barnaby]

I have an unusual question. The storage temperature range for an STM32WL is stated as: -65 to +150 °C.

We are looking at doing some particular tests at high temperatures for radiation exposure recovery, so some questions if anyone knows:

1. If we put the chips in an oven at 140 °C, powered off, for 6 months is there a likely hood of FLASH data loss ?

2. If the FLASH does lose data, I assume some factory settings could also be lost ?

3. Is it possible to reprogram the factory settings and the internal ROM code if this gets messed up ?

4. Would the STM32 still be accessible via the SWD interface even if the internal settings/FLASH is messed up ?

[STTwo-32]

Hello @Terry Barnaby 

To answer those questions and have complete guidance on that. I suggest you take contact with our Sales and marketing Teams or contact one of our FAEs. They may can provide you with such details.

Best Regards.

STTwo-32

[Terry Barnaby]

Ok, I can't see a way to contact ST Sales and Marketing on the ST website, so I will open a support ticket.

[Terry Barnaby]

Ok, I am not getting any useful answers from the ST support via tickets. Just getting answers like: "The storage is up to 150°C so no problem for data retention when the product is stored up to the tolerated temperature".

Obviously this is not useful as all FLASH will lose its contents after a time and much much quicker at higher temperatures.

1. Does anyone have any information on how long the STM32WL chips will likely retain their FLASH contents at 140C ?

2. Does anyone know what factory set FLASH data may be lost and if there would be a way of re-writing this if it does ?

[STTwo-32]

Hello, 

I've escalated this request internally (under internal ticket number 191753) and I will be back to you as soon as I have an answer. 

Best Regards.

STTwo-32