Strange behaviour with DC 3.3v step-up booster
my "mysensors" nodes are based upon a modified version of Easy/Newbie PCB (https://www.mysensors.org/hardware/newbie-pcb).
The nodes work fine with battery supply but without the step-up booster,
when I use a 3,3v DC step-up booster, the transmission with the gateway fails:
Starting sensor (RNNNA-, 2.0.0) TSM:INIT TSM:RADIO:OK TSM:FPAR TSP:MSG:SEND 255-255-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc: TSM:FPAR TSP:MSG:SEND 255-255-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc: TSM:FPAR TSP:MSG:SEND 255-255-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc: TSM:FPAR TSP:MSG:SEND 255-255-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc: !TSM:FPAR:FAIL !TSM:FAILURE
- 47uF capacitor beetween VCC and GND
- mysensors version is 2.0
Do you have any idea to solve the problem?
Thank you for your help!
@jumping step ups tend to make a lot of noise on the power lines (switching frequency) . Combined with the sensitive radio there is every reason to get into trouble.
A few possible remedies : a better quality step up. ; filter the power lines with a coil/capacitor or (better) include an LDO regulator ; get rid of the step up and use a lithium 3v battery.
I'm sure there is a lot of experience with the setup of this @sundberg84 board.
I have experienced this in a few nodes - and it was due to bad booster quality. I have had some success using a 0,1uF ceramic capacitor on the booster between out and gnd but sometimes its just not possible to get the noice away.
When i have ordered batches of 10 booster - its about 8 which is good and the other crap for different reasons (noice is one).
And just to confirm - you have only added the jumper on "BAT". If you have any other jumpers/connections that means the radio are getting its power from the booster which it should not. The radio should be feed directly from the battery for this reason.
Thanks for your answers!
I will try with a 0.1uF ceramic capacitor.
@sundberg84 yes, I only have added the jumper on "BAT"
yesterday I added a 0,1uF capacitor between 3,3V and GND pins and I tried 8 different step-up booster without success!
In the next days I will try different configurations to understand what is happening!
My personal (open to suggestions) preference is in using a 3v lithium cell (i.e. CR123, around €1 on aliexpress) which keeps a high voltage utill it's bitter end..
Hello @AWI thanks for you reply, I will read the document!
With other sensors I use LiOn Nokia/Samsung battery, and it's ok!
But I want to solve this little issue