EC25 +QTEMP reporting

According to the Hardware Guide,

Customers can execute AT+QTEMP command and get the maximum BB chip temperature from the first returned value.

This is what is reported by my modem: +QTEMP: 65,58,57
The first returned value looks pretty high for me, although I’ve seen even higher values (70+) earlier.

This is the report from another EC25 owner I found on Internet:

+QTEMP: 95,86,87
Lowers to 75 degrees and sometimes it goes up to 100. Box is not exposed to sun and it’s just warm.

At the same time I’ve seen reports with lower numbers and with 0 at the second place:

on initial bootup: +QTEMP: 28,0,23
After running for a half-hour with light internet use: +QTEMP: 34,0,27

So the question is whether all these numbers can be trusted? What value should we monitor to keep module safe, can we take that value as is or is any conversion required?

Dear Jfrog,
Thanks for your inquiry in Quectel forum.
For your question, please check the following picture.


Please note that the command just can give you for reference, it may also have some error. Thanks!

Thank you for this response, but there are a few questions remaining

+QADC is probably a typo here?
I do not see such description in the AT command manual I have, so I guess you’re referring to some newer document, would you be so kind and share it?
What is pmic? Should we monitor this parameter to keep it below 115?
xo is probably eXternal Oscillator or?
pa is probably Power Amplifier or?
Why we see so different results across the modems? Could that be caused by the difference in software versions and/or European vs. American variants?

Please check the following Functional Diagram of EC25 module, you can get the answers to your questions. Thanks!

Unfortunately, I see no answers to most of my questions yet :frowning:
Hardware guide says about “BB chip temperature”, where BB probably stands for BaseBand, but according to this diagram EC25 reports temperature from absolutely different components. You gave no explanation on the abbreviations used.
It is still unclear why on some modems the 2nd value of +QTEMP output is 0 and why the 1st value significantly varies between the modems that are not working in the extreme conditions.

What is pmic ? Should we monitor this parameter to keep it below 115?
xo is probably eXternal Oscillator or?
pa is probably Power Amplifier or?
The function diagram that i have send to you already answer your questions. PMIC is power management IC, XO is the 19.2M crystal oscillator which connected to PMIC, and PA is power amplifier IC.
And the command that send to you already explain the meaning of the three parameters, i have not see what you said “BB chip temperature”.Thanks!
Different module may have little different inside the module hardware design, and the software setting also different. So that why it varies between the modems.

Welcome to minicom 2.7.1

OPTIONS:                                                                     
Port /dev/ttyUSB2, 10:10:54                                                  
                                                                             
Press CTRL-A Z for help on special keys                                      
                                                                              
ati                                                                           
Quectel                                                                       
EC25                                                                          
Revision: EC25EFAR06A04M4G                                                    
                                                                             
OK                                                                           
ati                                     
Quectel                                 
EC25                                    
Revision: EC25EFAR06A04M4G              
                                        
OK                                      
at+qtemp
+QTEMP: 44,38,37
OK
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Thank you! I guess this device is not under heavy load and not in the very hot conditions?

+QTEMP: 46,43,42
OK

Now it gives that value.
Its GPS is open and connected to network. But not much traffic pass on it.

I’m referring to Quectel_EC25_Hardware_Design_V1.5 page 97:

When the maximum BB chip temperature reaches or exceeds 115°C, the module will disconnect from the network

Customers can execute AT+QTEMP command and get the maximum BB chip temperature from the first returned value.

So, according to this manual, the first reported by EC25 modem value is BB chip temperature.

Your answer goes against what is written in the documentation - you’re saying that the first reported value is <pmic_temp> and your diagram clearly shows that PMIC is not the same thing as Baseband. Please correct me if I’m wrong.

BTW, I see the same typo as in the screenshot you posted in Quectel_BG96_AT_Commands_Manual_V2.1

Response
+QADC: <pmic_temp>,<xo_temp>,<pa_temp>

Could it be that you’re referring to another module documentation?

And the main question still remains - why this first reported value goes so high on a modem that is not used in extreme conditions and is not under heavy load?

Dear Jfrog,
Please check the following latest EC25 hardware design document. Thanks!
Quectel_EC25_Hardware_Design_V2.3.pdf (1.5 MB)
The command return value have no any problem. The first value can be used to stands for BB chip temperature, our RD just use such value to check the module BB temperature. Thanks!
Just as i have said that it can calculate the reference value according the sensor inside the chip set, it may have some error, may not so accuracy. Just as the document said that only when the temperature is high 115C, it will disconnect the network. But the module operation temperature range: -35°C to +75°C and
the extended temperature range: -40°C to +85°C .
Thanks!

1 Like

thank you for the document and your explanations

Hello everyone!
I have an EC25-EU module with firmware EC25EUGAR06A03M4G.
The AT+QTEMP command does not show the temperature - displays OK and that’s it.
What is the reason and how to solve it?