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GPIO as Vdd for DS18B20

Posted: Sun Oct 14, 2018 9:44 am
by tpyo kingg
Can I safely use any GPIO pin as a +3.3V source? If so are there any tips or warnings to be aware of?

I have some DS18B20 temperature sensors and they use the 1-Wire protocol and have three pins: +3.3V (Vdd), data (DQ), and ground (GND). The RPi GPIO header has plenty of ground pins but not enough dedicated +3.3V pins for my plans.

Re: GPIO as Vdd for DS18B20

Posted: Sun Oct 14, 2018 10:29 am
by rpdom
You can use the same 3.3V power pin for all your sensors. Don't use the GPIO pins, they are not designed to supply power like that (although they would probably be ok with a few DS18B20s).

I have multiple DS18B20s running from a single Pi using just the three pins (Pin 1, pin 7 and pin 6) and one resistor.

Re: GPIO as Vdd for DS18B20

Posted: Sun Oct 14, 2018 10:48 am
by tpyo kingg
Thanks. I'll use the normal +3.3V then. More soldering / cable smithing / taping it is. :)