16x 12bit ADC CH at 3MSps with a reference voltage capable of going as low as 1.3μVPP Noise!
What if you need a fast DAQ system capable of sampling up to 16CH at 3Msps? In case of an SPI capable microcontroller or CPU, here’s a solution using MAXIM MAX11131AUI+.
The MAX11131 is a 16CH SAR ADC IC with 70dB SINAD and not more than 1 +/- LSB INL and DNL. By pairing it with a MAX6126, this 42M3 module will give you 12bit of resolution from 0V to 3VDC.
It is worth noting that this implementation requires a dual rail power supply, possibly with a low noise output, at both 5 and 3.3V (with MAX power out 50mW).
By controlling the module via a Raspberry Pi, it is in principle possible to hook up multiple modules so that one can build a pretty large DAQ system with many ADC channels (this is what I’m doing to build a 320CH ADC DAQ at INFN, even thou there I’m integrating everything on one single board by doing a copy and paste of this module on a bigger PCB).
Arduino (Atmega 328P Microcontroller from Atmel (Microchip)) should be able to read multiple modules, but not at 3MSPS since that speed requires a 48MHz clocked bus.
Note: CS (chip select) and EOC (end of Conversion) pins are pulled high with a general purpose 10k resistor, this means that in normal operation ADC is disabled and EOC line pulled at 3.3V. When sampling EOC will be pulled low by the MAX11131 at each end of the conversion cycle.
DOWNLOAD FULL SCHEMATIC and BOM [PDF]
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Hi nadim, big fan of your work and thanks for sharing with the rest of the world. Every single article is a master piece.
I wanted to click on the download link to watch the ad but my Antivirus blocked it. I guess that needs an update.
Hi Dijachu, thanks for the kind words and for reporting the issue!
I’ve decided that it is better to drop the advertisement link ad insert a Paypal donation link.
The files are being uploaded on GitLab. I took care of uploading this PCB first for you.
Link to GiLab repo:
Link to Paypal donation (momentary): https://www.paypal.com/donate/?token=Xiv4luOHOHL2cF2D7fmBATnUKzE2VPDfc-5W2z_xyM4qDNK_gZKcFnJaI-UIgA22btGa5G&country.x=IT&locale.x=IT
Let me know if you have any issues with the repo!