Availability of SAM E70, rev. C

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Recently I switched to Atmel and bought a SAM E70 Xperienced board. I've managed to find the information I need in the 2000-page long datasheet (not sure why this is still called a "sheet"). Anyways, to get used to Atmel Studio 7 and the architecture of the SAM E70, I created code to read the ADC at 100 kHz and write that to the DAC. In order to interpolate the results, I wanted to deploy OSR for interpolation purposes, only to find out after several hours of experimenting that the OSR both in revision A and B are non-functional according to an errata sheet. D'oh!

 

What options do I have? Do I need to build an analog low-pass filter at the DAC output? Are there other Atmel solutions in the market with a fully function DAC? The way it is implemented, it seems the DAC is not really usable for audio purposes.

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Dear Syntie,

 

as far as I know you can come close to a DAC output frequency of 1MHz in the SAME70 device (regardless A or B revision). So, dependent on your needs about the output frequency you might can calculate the interpolation by you own code. Certainly, this requires a lot of computing resources. You might need to enable the D and I Cache or put the code in the TCM memory. 

Personally I think the whole AFEC is full of nice features but most of them are not suitable for really mid-high performance use. Just have a look at the number of error bits for the ADC part or the non existing routing of the DAC to an output pin if it is used for the analog comperator function. If you are in the area of low-mid performance use the AFEC is really fine.

To wait for a C revision may turn out to be an endless wait. Currently there is no much movement in this area of products at Microchip (if you compare with ST or NXP for example). Personally I would rather expect a dualcore device with M4/M7 and A5x in the future than a C revision of the SAME70.

 

Best Regards

Markus

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I2s audio dacs are cheap and will work much better than the on chip dac.

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Hi Markus, thanks for the information. Looks like the competition doesn't really have much better performance to offer for their ADC's and DAC's, so I'll stick to SAM E70 for now. I'll just add an external low-pass filter. Not the prettiest solution but it'll do.