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Raspberry Pi Zero W, Voltage GPIO's

Wed Feb 21, 2024 9:27 pm

i have several sensors that i want to connect to my pi which are water temp, turbidity, TDS (total dissolved solids), and Ph sensors.
i would like to know if these sensors needs a 3.3v or 5v power?
another question that is there any thing that i can use to produce more power GPIO's either 3.3v or 5v power.
please let me know if you have the knowledge.

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Re: Raspberry Pi Zero W, Voltage GPIO's

Wed Feb 21, 2024 10:35 pm

The operating voltage of the sensor will be given in the sensor datasheet, so look at those (12V, 5V, 3.3V etc.)
More power GPIOs - connect several wires to one 5V (or 3.3V) pin. They will all be 5V (or 3V3) unless you try to take too much current.
Look at the Pi datasheet to see the maximum current draw from the 5V and 3V3 pins.
Also the Pi GPIO inputs are 3.3V maximum.
And the sensors may have analog outputs so you will need an external analog to digital converter (ADC) as the Pi does not have an ADC.
Plus, some sensors use an I2C or SPI or 1-Wire interface - check sensor datasheet.
Look at this for GPIO reference and I2C pins etc. https://pinout.xyz/

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