Hi,

I am using the ADC converter in the ADuCM320 with the sequencer and DMA. I get correct results from the conversion and the system is functionally working fine.

However, when checking the time it takes to convert a sequence of ADC channels I get a different result to what I would expect.

When running at 80ksps (12.5us per channel) and having a sequence of N channels the conversion time is (12,5 x N)+25 us.

When running at 40ksps (25us per channel) and having a sequence of N channels the conversion time is (25 x N)+50 us.

What I would expect is (12.5xN) us and (25xN) us. So, it looks like it takes an additional 2 conversion cycles to every sequence. I tried this for a number of values for N between 5 and 23, and the result seems very reproducible.

Question: Does the hardware indeed add 2 additional cycles to the conversion timing by design, or is it more likely an error in one of the settings I am making ?

THX,

Theo

Hi Theo,

What you have seen should be matched with design. After the sequencer complete, ~ 2 ADC conversion cycles will be added to wait for ADC conversion complete.

Thanks,

Bruce