Cheap way to connect multiple 1-wire sensors?

Forum 2005-2010 (read only) Hardware Interfacing
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I'm working on a datalogging project and have multiple (at least 4) DS18B20 1-wire temperature sensors to connect to the Arduino board. The bus architecture of the 1-wire interface means that all the data pins of the sensors can be connected together and all the grounds can also be connected together.

My idea is to be able to connect the sensors together in one area and then have just one cable coming back from that junction to the Arduino. I would like to be able to plug in and unplug sensors as needed (so I don't need to solder/unsolder wires) so I'd like some sort of jack/connector system that is fairly robust.

Does anyone have any suggestions for a method that is fairly cheap and robust? I've thought of RJ11, RJ45, and 3.5mm headphone jacks. I'm thinking that if I could find at least a 4-to-1 splitter for cheap so I don't need to buy the jacks and install them in a box that would probably be the best. I also remember hearing about some sort of "tap" that was used for RJ11 telephone cables where you could run the main line and then push the tap onto the line and then you would be able to join another line to it, but I can't seem to find this again, maybe I'm using the wrong term.

Does anyone have any opinions? Thanks.

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Not being rude, do a search on the forums, multiple dallas DS18 sensors on the same line has been done many times, you can learn a lot from the threads :slight_smile: Its entirely possible to do exactly what you want to do, I'm running 3 at the moment and a sensiron temp/humidity sensor as well.

depending how you expect to split the sensors up, you should be able to make a small board up with say, 4 stereo headphone jacks (1 for each sensor) connect them gnd to gnd, L to L and R to R on the sockets, take that off to another 3.5mm (or whatever 3 core cable you want) and then split the lines off to data, gnd and vcc on the arduino.

Oh and you'll have to be careful with power supply and timings on longer cables.

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I also remember hearing about some sort of "tap" that was used for RJ11 telephone cables

The tap you use in telephone cables an antenna feeds and the like is to split low impedance lines to stop multiple low impedance loads shorting out the line. At it's simplest a tap consists two resistors joined at one end with. So each thing has a series resistor.

Now the 1 wire bus is high impedance, that means you can just wire as many devices to it as you want because the devices are high impedance and don't load the bus. Therefore you don't need any special taps or wiring just string them along across the same pair of wires.