Hi All, I'm trying to setup a simple VI on a myRIO-1900 to use a digital potentiometer as a variable resistor. I have preciously used an SPI dpot with success however I am having issues when switching to an i2C controlled dpot. Following the datasheet found here ( http://www.analog.com/media/en/technical-documentation/data-sheets/AD5241_5242.pdf ) I have made the following connections. [1] A1 -> 5V [2] W1 -> Analog Input [3] B1 -> DGND [4] Vdd -> 5V [5] SHDN -> Vdd (5V) [6] SCL -> [32] I2C SCL[7] SDA -> [34] I2C SDA [8] AD0 -> 0V analog output [9] AD1 -> 0V analog output [10] DGND -> DGND [11] Vss -> DGND [12-14] -> No connections When I make these connections and run the following VI with the i2C express VI set to write, I end up reading a constant voltage which does not change with variation of the 8bit vertical point slide input. Furthermore, I am experiencing some chip overheating if the VI runs for too long which shouldn't be occuring. There are several areas which I think the error may be arising from: 1. Pinout connections outlined above are incorrect. 2. The slave address is incorrect. I am unsure whether I should be sending analog or digital outputs to the AD pins to define the slave address. the datasheet states " Package pin programmable address bits. Must be matched with the logic states at Pin AD1 and Pin AD0." I hav e set both to a logic low (I think) and therefore assume that AD0 and AD1 are 00. So the slave address bit is 01011 then 00 whch is 255. I have also tried setting both to boolean false with a digital output but I expereince the same problems. 3. Incorrect soldering. The chip is a SOIC chip and I have hand soldered it onto an adaptor board (winslow w9502RC) so that I can sit it into my breadboard. Does anyone have an idea what the problem/s might be? Cheers, Ben

My assumption was a 1D array of two elements, the first being the instruction byte and the second being the data byte. However, that's just my educated guess; if you're looking for more information, I might ask the makers of the AD5242 for more information.

Digital I/O

i2C Digital Potentiometer

Solved!

Thank you TheXiadow, finally i found that the problem was with my hardware board.I fixed it and now DigitalPot is working fine.Thanks

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Digital I/O

i2C Digital Potentiometer

Re: i2C Digital Potentiometer