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Author Topic: Matrix of Analog Inputs - Looking for Driver Chip Suggestion  (Read 884 times)
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Hello everyone,

I am trying to figure out how to control a matrix of thermistor sensors. I see there is an example of what I'm talking about for Servo motors, but I don't know what to search for to find something like this for analog inputs.

https://www.adafruit.com/products/815

Any suggestions?

Kevin
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Are they inputs or output ?   You don't really "control" inputs.

There are a bunch of different IC's and modules available which will read multiple analog inputs
and then your microcontroller can read the value through I2C or SPI.

There are also IC's which will connect multiple external input analog signals to one arduino
analog input pin,   so you alternately connect the different inputs and sample them one
at a time.

Or you can use the one-wire device  which you can connect multiple instances of to a single line.
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They are analog inputs.

What I an trying to do is establish a field of about 24 thermistors. There is not enough analog in pins for this even on the mega, so I was hoping there was a breakout board that would be able to receive code from multiple sensors and feed it to the controller so I can control servo outputs based on a certain algorithm for the analog input matrix.

In the simplest form I want it to be able to detect which thermistor has the highest reading. I could take the rest of the project from there, but the hardware to set up that matrix is eluding me.

Would you have any resources for how I might accomplish this through ICs? The catch is that I can't have them read one at a time like you said, I need it to read the whole matrix, and identify the highest read.
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Will a shift register like this accomplish what I'm talking about?

https://www.sparkfun.com/products/733?
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I would use 3 MCP3208 ADC chips.
12-bit readings, read via SPI, easy to use.

http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en010534
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Yeah, they are good,  about $5 each.  That is probably the easiest solution to your problem.
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Thanks. I will try this.
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