FPGA DAC

[DanielNikolajSand]

Hi Everyone.

I have gotten the idea that I would like to try and make my own DAC from my sbRIO evalution FPGA.

I would like to make a 0-10V output with a DAC and an op-amp from a bipolar PSU +12 / -12.

Temp. Compensation will have to come later unless it's included in the op-amp.

Have any of you experience with this and what would be the preferred protocol to start with, I2C or ISP?

I think 12 bits would be enough for me to start with, and something that is not multiplexed.

If any of you have a code or schematic to share it would be really great, also what should I look for when ordering components.

I have a few ADI books on the subject to guide me.

Please take note that I am not that familiar with electronics. I.e I have no education in this field, self taught.

Any guidance and what components to start with would be very helpful.

Thank you in advance.

/Daniel

[KHartley]

Daniel,

Are you wanting to use the FPGA to talk to a Digital to Analog Converter? 

For the SOM that just released we've been using PMODs to test some functionality of the carrier board they are preprototyped boards that break out the specific IC the company manufactures to a .1" header. 

Digilent sells several. Maxim Integrated produces their own as well. If you are not looking at designing the DAC yourself this could be a quick option to test out a specific DACs.

If you do intend to make your own DAC there are a few ways to do this. You don't necessarily need an I2C interface as this just allows you to use less pins on the fpga to talk to the single IC. 

[DanielNikolajSand]

Hi Kyle,

Thank you for the reply,

To be honest I have no idea if designing my own DAC will be too difficult for me to start with, I do see the benefit of getting the software running on a board like you are talking about before I venture into something more advanced.

Do you have a link for the boards you were talking about?

All the best

Daniel

[DanielNikolajSand]

Hi Again,

Found the PMOD's. Looks good, couldn't find any Maxim boards though.

Was kind of hoping for something where you could solder the op-amp you need to the board, but it doesn't seem to exist.

None of the PMOD's are I2C, but SPI is also fine.

Br. Daniel

[KHartley]

Here is the closest I can get for the PMODs from MAXIM. 

http://www.maximintegrated.com/en/design/reference-design-center.html

Change the search parameters to analog and the last one to reference design. 

Spark Fun may be a good source for diy but very few DACs share the same footprint or reference layout. You can always look at the reference design and layout a PCB and have it printed and populate it by hand. 

[DanielNikolajSand]

Thanks Kyle, will let you know how it goes