Daily Archives: June 11, 2011

Reader question: Shouldn’t the (effective) bandwidth of the ADC or DAC also be reported in the titles?

Ameya Bhide posted a question in the Q&A section. Ameya wrote:

Hi Bengt,

After being lost in the world of Converters for a while, I always have this fundamental question as follows:-

Industries, Publications always talk about GSamples/sec of an ADC or a DAC and the higher the rate, better the converter is. But very few talk about the Bandwidth in the title of the ADC. Even in publications, I always see the title as ” An XGsamples/sec ADC” where as I think it should be “An X Gsamples/sec Y Mhz BW ADC” since many of these converters do not retain performance up to Nyquist.

Even when looking at the TI ADC’s I need to search the data sheet to find the real bandwidth of the ADC. Shouldn’t the sample rate and BW be always reported together so that one quickly understands what the capabilities of the ADC are?

Could you comment on this?


Good question Ameya, and one that touches on a broader topic (scientific reporting practices) that I’ve been planning to bring up for a while. This is a good starting point. Perhaps your question was mostly concerning data sheets? Either way, I’d like to broaden it to include scientific papers as well.

So blog readers, what do you think?

  • Is there an inflation in paper/data-sheet titles?
  • Should we require paper titles to more accurately describe the actual bandwidth of the ADC?
  • Is effective resolution bandwidth (ERBW) the best measure?

If there is an inflation, and a practice to boost performance in the titles, what will happen to the pioneers which put more complete (potentially less impressive) information in the titles? Rejected papers and loss of business? Is the target audience really that gullible? Don’t they read the content of a data sheet or paper? How long can a paper/data-sheet title be 😉 … etc.