Q2687RD temperature sensor (ADC3)


#1

Hi,

I’ve just received an Q2687RD (actually, it’s an ES - Engineering Sample). What I found weird is the behavior of ADC3 (internal temperature sensor), i.e. it always returns 0 when read in analog mode:

at+adc?
+ADC: 3296,1268,39,0
OK
at+adc=0,3
+ADC: 0,0
OK
at+adc=1,3
+ADC: 1,880

Can anyone confirm this? Is this an intended behavior, i.e. is this 880 value actually in mV? On Q2687G I get:

at+adc?
+ADC: 4068,1335,1073,726
OK
at+adc=0,3
+ADC: 0,726
OK
at+adc=1,3
+ADC: 1,656

#2

Hi
I guess the value comes in mv only in case if select the analog mode hence the value(i.e 880) that you are receiving in case of digital mode is not in mv.


#3

Surely, if you’re in touch with someone who can give you an engineering sample, then they should be able to provide support on it?!


#4

I did try to investigate the problem myself and I did ask my distributor (who sent me the ES), but with no luck, i.e. no answer.

Please don’t assume that everyone coming here is lazy and just seeks for a complete answer without doing anything themselves to try to come to a solution.


#5

Sorry.

But it’s always good to mention what steps you have taken so far - not least so that you won’t be mistaken for one of the all-too-frequent cases that just seeks for a complete answer without doing anything themselves :frowning:


#6

True, my fault :slight_smile:


#7

How to convert ADC3 to celсium ?

where are write about adc3 in documentations?


#8

Refer to the latest PTS (available in the down loads section)
See sec 4.15
VTemp (V) = -0.013 x Temperature (°C) + 1.182