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#clock TMP36 #clock


DJ7AO
 

Hi folks!

I just wonder why the the shown temperature in the clock module  is always going up and down several degrees - there`s no reliable display.
I`m using 2 x TMP36 with the same effects in 3 different clock modules. I also changed the step-down-converter to a 7805 regulator and a battery. I always have the same effect with the jumping temperature display. Any hints ?

73
Stefan Reyers - DJ7AO

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N3MNT
 

The manufacturers spec on the TMP 36 is ±2°C accuracy over temperature (typ)


Nigel Dudley
 

 

My clock does the same, it is a known problem as there is no smoothing algorithm in the software and is on Hans to do list

Nigel VK6NI

 


Brian Helm
 

0.1uF cap from pin 2 (vout) to pin 3 (gnd) on TMP36 sensor fixed this for me.
This also fixed the temp variation I saw while transmitting from my HF rig.
 TMP36 datasheet also shows 0.1uF cap in their examples from pin 1 to pin 3 (supply voltage).  I already had this in place and it didn't fix the problem.  


KEN G4APB
 

Hi all, this was fixed in version c1.03...
ADC now averages 100 samples to reduce noise (for temperature calculation etc)

73 Ken G4APB