16+ Analog Input Options for Beaglebone

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#1

I would like to use the BeagleBone to acquire 16 analog signals. The transducers will be a mix of resistive temperature and current sensors. The temperature sensors will produce a signal between 0~5V and the current transformers will output of 0~0.333V. The BeagleBone Black is limited to 7 analog inputs. I was not able to find a cape that offers 16 analog inputs.

  1. Does a BeagleBone Black cape exist that will multiplex and signal condition 16 analog signals (0~5V).
  2. If this does not exist, can one of the BeagleBone experts recommend an alternative.

Thanks in advance.

#2

A common practice to increase the number of ADC channels is to use an “Analog Multiplexer” (MUX). Use a few GPIO bits to control the addressing.
You can provide a single point buffer to support the 0-5 to 0-1.8V scaling.
Cheers

#3

It might be easiest to purchase a few multi-channel, 5V compatible A/D converter ICs that feature an I2C or SPI interface, and use that interface to connect them to the BB. A quick search at a distributor’s website will give you multiple devices to choose from, like the MCP3002.