Hi guys I bought these 12v relay modules and I would like to connect them to arduino: https://bit.ly/3KClg9U
They work with a positive logic and have the gnd in common. I was thinking of using an uln2003 like this:
would work?
Hello gshokk
Did you check to data sheet of the ULN2003, didn´t you?
Have a nice day and enjoy coding in C++.
You probably want a high side (source) driver e.g. udn2981 but I can't fully understand your relay data sheet.
Edit
I could change the page to English so it is clear. You can't use a low side driver such as the ULN2003 because the GND is common. Either the relay coils are polarised or there are built in flyback diodes.
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so how can i do?
With one of these:
TD62783AP
UDN2981
UTC 62783
Are there no other ways? I have seen that these chips come exclusively from china and take too long
Not exclusively: https://www.reichelt.com/ch/de/8-kanal-hochspannungsquellentreiber-500-ma-dil-18-udn-2981-p22008.html?r=1
However, you can also use a MIC2981 from say Mouser
Maybe the relays have 12V coils, but where is it that the input logic is "12V"?
It certainly look like they would 
sorry, another question. I can command a 3w 12v solenoid valve directly (without relay) from the UDN 2981. It should do it in theory
Possibly. The total load for a UDN 2981 is 500mA. However that also depends on the package not getting too hot (see the datasheet for a similarly vague statement).
Your relay coils appear to need about 50mA each. Your solenoid(s) 250mA.
If you have multiple solenoids, then drive each with an N channel logic level mosfet on the low side and add a flyback diode across the coil.
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