16-bit AD converter

Hi All - I'm looking for a companion board for Beagleboard (or bone)
to do some data acquisition and processing.

(1) I can't find info on AD capabilities of Beagle boards, ADC is
mentioned
in schematics but channels/drivers/resolution/speed etc are
mysterious ?

(2) Anybody making a companion board for 16-bit data acquisition ?

Thanks in advance,
Best Regards, Dave

The ADC is a peripheral on the AM3359 processor. All the BeagleBone does is connect those signals to the expansion header. You need to refer to the AM3359 datasheet and Technical Reference Manual for more information on the ADCs. All processor specific information needs to come form these sources. Copy all that information into the System Reference Manual would be redundant and make for a very very large document!

http://www.ti.com/product/am3359

Gerald

Thanks Gerald !
This confirms the built-in ADC is only 12-bit. So:
(2) Anybody making a companion board for 16-bit data acquisition ?
Thanks in advance,
Best Regards, Dave

if i remembered correctly, the acquired signals should not exceed 1.8V

KP

I am looking for a 16-bit resolution ADC solution.
The voltage levels are not particularly important...
Thanks in advance for any suggestions,
Best Regards, Dave

Thee are several SPI or I2C based ones depending on your sample rate requirements.

Gerald

Thanks Gerald - Can you provide any links ?
I was unable to find one via http://beagleboard.org/
Thanks again,
Best Regards, Dave

I would suggest that you just google I2C A/D or SPI A/D. Or maybe go to Mouser or DigiKey and search there for the parts. At this point in time, I don’t think there is a board for the BeagleBone, but I would not be surprised to see one in the next several months.

Gerald

Thanks Gerald - I am a frequent component customer
at DigiKey, Mouser, and others, however:

I am looking for an off-the-shelf, ready-to-go,
companion board solution for Beagle, without designing
new boards and/or writing drivers.

Looks like I might have to go the PC104 route to get
ready-made peripheral boards...

Thanks again,
Best Regards, Dave

The BeagleBoard and BeagleBoard-xM have an audio input. I am not sure if that would work for you or not.

Gerald

Thanks Gerald - I am a frequent component customer
at DigiKey, Mouser, and others, however:

I am looking for an off-the-shelf, ready-to-go,
companion board solution for Beagle, without designing
new boards and/or writing drivers.

Looks like I might have to go the PC104 route to get
ready-made peripheral boards...

I would be surprised if there were no I2C boards. Have you tried
places like SparkFun?

For instance http://www.sparkfun.com/products/8736 is a 12 bit
I2C AD converter.

David

Thanks, yes, I tried Sparkfun, they don't have 16-bit ADs.
No, the audio channel won't do it...
Guess I'll have to go with a different platform,
Thanks again,
Best Regards, Dave

This should work for you. It is SPI based.

http://search.digikey.com/us/en/products/ADS8321E%2F250/ADS8321ETR-ND/295542

Gerald

I have designed a board (known uncreatively as the BeagleDAQ) for doing
large-scale data acquisition from the BeagleBoard. It has capacity for
four 8-channel 16-bit ADC and DAC converters (thus up to 32 ADC channels
and 32 DAC channels). It is currently being used successfully in an
experiment. Unfortunately, due to the incredibly broken scientific
publishing system, I have been asked to remove the Wiki page from public
sight. That being said, if you are interested feel free to contact me
privately.

That being said, there is also Mark Haun's DAQ board, built around the
PandaDAQ, which looks quite promising. It is still in the early stages
of development, however.

Cheers,

- Ben

I can suggest the following list of converters

DESCRIPTION PART MOR INFO

ADC 12BIT 8CH 50-200KSPS 16TSSOP ADC128S022CIMT-ND http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=ADC128S022CIMT-ND
IC DATA ACQ SYS 12BIT 20-SOIC LTC1290 http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=LTC1290DCSW%23PBF-ND
IC ADC 16BIT 250KSPS 8CH 20LFCSP AD7689 http://search.digikey.com/us/en/products/AD7689ACPZ/AD7689ACPZ-ND/2027811
IC ADC 12BIT 16CH 1MSPS 28TSSOP AD7490 http://search.digikey.com/us/en/products/AD7490BRUZ/AD7490BRUZ-ND/819881
IC ADC 8CH 16BIT 100KSPS 28-SSOP LTC1859 http://search.digikey.com/us/en/products/LTC1859CG%23PBF/LTC1859CG%23PBF-ND/963908
IC ADC 16BIT 16CH DELT-SIG 48QFN ADS1158IRTCT http://search.digikey.com/us/en/products/ADS1158IRTCT/296-23494-1-ND/1880924

I hope to be helpful in your purposes,

meindert.scholte@gmail.com writes:

Hi Ben,

Hey,

I am looking for ways to do some data acquisition with the new Beagleboard
Black. I need 16 bit resolution and was lookingon the Internet for
information when I stumbled on this blog. Can you share some information
about your adc board? Do you have schematics, maybe print layout? Any help
is welcome.

I've put together a number of designs over the years. This began with
the BeagleDAQ[1], which was an unreasonably large daughterboard for the
BeagleBoard built for large-scale (32 DAC and 32 ADC channels)
data-acquisition. The board was extremely simple, consisting of little
more than a number of SPI DACs and ADCs hanging off of the Beagle's two
McSPI busses. Unfortunately, I soon realized that I wouldn't be able to
squeeze the feedback rates I needed out of this hardware.

Consequently, a bit later I put together the uDAQ[2] which is a
daughterboard for the BeagleBoard XM intended for running a feedback
loop. This consisted of an STM32F3 MCU (with integrated 12-bit ADCs) and
a 16-bit 8-channel DAC. While the board worked, I found it was rather
awkward to get the two processors to communicate (given only SPI and a
UART). Moreover, a few hardware bugs drew me away from this approach.

Recently I started looking again at this and decided to go with a less
BeagleBoard-specific approach. This device, the mDAQ[3], consists of an
LPC4330 ARM Cortex M3/M0 processor and is designed to operate either
autonomously or as a USB device (although a couple UARTs are also
brought out). I'm currently waiting to receive the PCBs, but I suspect
this will be the last in my string of data acquisition board
designs.

You can find designs for each of these on Github (URLs below). Each is
designed with the geda toolchain (e.g. gschem and pcb) and is offered
under an open source license. See the appropriate repository for details.

Cheers,

- Ben

[1] https://github.com/bgamari/beagle-daq
[2] https://github.com/bgamari/udaq
[3] https://github.com/bgamari/mdaq