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I am trying to use this multiplexer with a raspberry pi and am having difficulty getting it to work.

here is the datasheet: https://datasheets.maximintegrated.com/en/ds/MAX378-MAX379.pdf

I think my problem lies with the pin configuration, specifically V+ and V- as shown here: enter image description here

to test this I have the mux on a breadboard and have an LED connected to IN1 and +5v coming from the pi

The datasheet shows that the recommended power supply is 15v so I have a 15v dc transformer connected to V+. The negative from the transformer is connected to the "-" rail on the breadboard. V- on the mux is connected to the "-" rail on the breadboard (I've also tried just using the 5v power source and ground from the pi to no avail)

I don't have anything connected to A0, A1, A2 since the truth table on the datasheet shows that IN1 will be switched on if they are 0 and EN is 1

I have the OUT pin on the mux connected to ground from the pi

The expected result is that the LED will light up when EN gets voltage from a GPIO on the pi. I've confirmed that the gpio pin I'm using does go high when I trigger it in a python console but when I connect it to EN, IN1 and OUT don't appear to be connecting as I would expect.

I'm a total newb when it comes to this stuff so I'm hoping what I'm doing wrong is fairly obvious and someone can help me get this figured out!

Thanks in advanced!

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You need a true Dual rail power supply - That is to say (+V) - 0V(GND) - (-V) The +Ve must be a positive voltage relative to GND and the -Ve must be a negative voltage relative to the GND.

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