Why are two TJMAX parameters in the Datasheet, and which one should I refer to?

[TIM8]

In the Datasheet, Table 16 specifies TJMAX as 150 °C, but Table 17 indicates the TJ range as -40~130 °C, which one should I refer to?

Table 16. Thermal characteristics
Symbol Ratings Value Unit
TSTG Storage temperature range –65 to +150 °C
TJ  Maximum junction temperature 150 °C

Table 17. General operating conditions

TJ Junction temperature range    Suffix 6 version -40 105  °C    Suffix 3 version -40 130

[Andrew Neil]

Welcome to the forum.

You haven't said what specific datasheet (including revision) you're referring to!

Please post a link and/or a screenshot.

How to write your question to maximize your chances to find a solution

PS:

Taking this one at random, Table 16 comes under Absolute Maximum ratings:

while Table 17 is under Operating Conditions:

So, yes - they are referring to different things

[Ozone]

As indicated, it is always useful to fully identify the document/part you speak about.

Table 16. Thermal characteristics
Symbol Ratings Value Unit
TSTG Storage temperature range –65 to +150 °C
TJ  Maximum junction temperature 150 °C

Table 17. General operating conditions
TJ Junction temperature range    Suffix 6 version -40 105  °C    Suffix 3 version -40 130

I highlighted the usual interpretation of those terms.
"Storage" means "not operating", no supply voltages applied.

[TIM8]

Hello, the table I mentioned are in the Datasheet of STM32G474xB Revision 4.

Thank you in advance.

[Andrew Neil]

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@Ozone wrote:

Table 16. Thermal characteristics
Symbol Ratings Value Unit
TSTG Storage temperature range –65 to +150 °C
TJ  Maximum junction temperature 150 °C

Table 17. General operating conditions
TJ Junction temperature range    Suffix 6 version -40 105  °C    Suffix 3 version -40 130

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But @TIM8 was referring to the Junction temperature (TJ) in both tables - which differs.

See the PS to my previous reply: Table 16 is Absolute Maxima; Table 17 is Operating Conditions.

[Issamos · Accepted solution]

Hello @TIM8 

As you can see in the first paragraph of the chapter 5.2 of the DS12288:

Stresses above the absolute maximum ratings listed in Table 14: Voltage characteristics, Table 15: Current characteristics and Table 16: Thermal characteristics may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these conditions is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. Device mission profile (application conditions) is compliant with JEDEC JESD47 qualification standard, extended mission profiles are available on demand.

So, for operation conditions , you should refer to table 17 value.

By the way @Imen.D , on the paragraph mentioned previously, « Exposure to maximum rating conditions for extended periods may affect device reliability. » is repeated twice. It seems to be a typo that should be corrected.

Best Regards.

II

[Andrew Neil]

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@TIM8 wrote:

Hello, the table I mentioned are in the Datasheet of STM32G474xB Revision 4.

---

Thanks.

So, indeed:

• Table 16 is Absolute Maximum ratings;
• Table 17 is Operating Conditions.

It is to be expected that Absolute Maximum ratings will be higher than the Operating limits; you will see the same if you compare other Operating Conditions tables to Table 16.

This applies generally across all electronics components - not specific to STM32.

[Andrew Neil]

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@Issamos wrote:

By the way @Imen.D , on the paragraph mentioned previously, « Exposure to maximum rating conditions for extended periods may affect device reliability. » is repeated twice. 

---

Indeed.

@Imen.D and the same appears in the DS12983 which I posted earlier - I guess this is a copy-&-paste error, and is likely repeated in other datasheets...

[Imen.D]

Hello @Issamos , @Andrew Neil ,

Thank you for bringing this to our attention.

This is a known issue highlighted in the STM32 MCU datasheets: Expected preliminary updates  for DS13122 Rev4 and it will be checked/fixed for all impacted documents.

[TIM8]

Understood, thank you for the response.