Advice on a differential signal IC like SN75176A

Hi there!

I'm working on a project that is going to require me to have two Arduino's talk over serial over some CAT5 cable about 10 feet long. In initial tests, communication has been fine when wired together close together, but noisy and reliable over longer cable lengths

I found this post on how to use a differential signal IC for controlling neopixels over a distance of CAT5:

This seems like just the thing for my problem. However, the chip mentioned in that post seems to be either transmit or receive. I was wondering if anyone knows of a differential signalling IC I could have on each Arduino, so I can have serial RX/TX encoded and decoded at both ends of the Cat5.


You must be sending at some horrendous baud rate to have " but noisy and reliable over longer cable lengths".

That tells me you DO NOT have a protocol that can detect and correct errors. Why not?


The SN75176A can do transmit and receive but only one or the other at any given time (i.e. half-duplex.) Do you need to be transmitting and receiving at the same time?

If you’re doing full duplex, the old standby was the SN75179 but that’s an old design chip. Still available, cheap and okay but there are newer designs with higher and better ESD protection.

Use DigiKey’s parametric search for “interface, transceiver” then select RS422 and 423 types with at least 1/1 receiver/transmitter and take your pick.

To make it clear: use only matching line transmitters and receivers.

Thank you all for the advice on this! Full duplex was a key phrase I needed to know.

I’ve ordered a few SN75179 to practice with.

I did that digikey search, but I found the bazillion results pretty inscrutable.

@WattsThat, could you recommend a similar IC with better ESD that comes in a DIP package? I would want full duplex, 5V input voltage, and the application would be to send serial Tx/Rx between two Unos over 15ft of Cat 5.