To start with, the ADC that will meet your requirements: http://www.ti.com/product/ads1278 <http://www.ti.com/product/ads1278>
This is a 24 bit ADC sampling at 144kHz. To sample 50V, you will need a signal conditioning front end that will scale your input voltage to a level compatible with your ADC. A simple resistor divider won’t work because of the error it will introduce each time the ADC samples the data. You need an opamp based signal conditioning circuit to scale the input voltage. The ADS1278 uses SPI for communications and that can be interfaced to the BBB without difficulty. However, you will need to write a device driver as spidev won’t be fast enough. Also, I suspect that you will want to sample continuously so a ping-pong or cyclical buffer (DMAengine terminology) will do what you want. Regards, John > On Dec 3, 2015, at 2:07 PM, Chelsea Orefice <coref...@smith.edu> wrote: > > Hi everyone, > > I am new to the world of using MCUs and am looking for some assistance on a > project that I am currently working on. To sum things up quickly, I am > building a data aggregation unit that can convert analog voltage readings to > digital values that is to be stored on a USB or SD card. The DAU will collect > 3 types of signals, a buffer signal, clipped signal, and a signal passed > through a LPF. In the end, the data should be stored as either a MatLab file > or .xml file. However, I am facing a few road blocks relating to my design. > > 1.) I need to use a 24 bit ADC for high resolution purposes based on design > requirements that were just given to me as I will be collecting data from > .1mV to 50V and it has to have a high sample speed rate. Has anyone connected > an external ADC to the BBB? If so, what was the brand of your external ADC? > How did you connect the ADC to the BBB? (It'd be greatly appreciated to be > able to see a design). > > 2.) If you have had a similar project to this, was wondering how you went > about it. Any advice would be greatly appreciated. > > > As I said before, all of this is very new to me. So thank you for taking the > time to help me out. > > Chelsea > > > > -- > For more options, visit http://beagleboard.org/discuss > <http://beagleboard.org/discuss> > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to beagleboard+unsubscr...@googlegroups.com > <mailto:beagleboard+unsubscr...@googlegroups.com>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
