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Altera_Forum's avatar
Altera_Forum
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19 years ago

Why Altera do not integrate ADC into CPLD?

Engineers welcome the integrated solution.

It do help to save board size and save time on developing and debug work.

As the CPLD performance is limited, so middle performance ADC is enough for CPLD.:) :) :)

8 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    I had a similar discussion a few years back. The trouble is, what to _you_ consider a middle performance ADC? 10-bit at 100KHz? 12-bit at 1MHz?

    Audio people will want more bits but lower update rates, video people will want fewer bits but high update rates, industrial people will be all over the place. Bo matter what ADC will go into the MAX2, the audience will always find the solution bad ;-)
  • Altera_Forum's avatar
    Altera_Forum
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    No such a idea is well for anyone.

    Good product defination can get enough ROI.

    And I think accuracy(X bits) is related to die size, sample rate is related to silicon process performance.

    Based on current MAXII fmax performance, I also think sample rate performance should not be Altera's problem.

    Just the balance between accuracy/market coverage vs die size/cost
  • Altera_Forum's avatar
    Altera_Forum
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    Beside what has been mentioned, I doubt a fair number of significant bit is possible when the high currents inside a CPLD are switching. The ADC manufacturer hint that the ADCs need to be connected to the analog GND, which clearly is not the GND where the CPLD is on.

    Rene
  • Altera_Forum's avatar
    Altera_Forum
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    I think, the best thing Altera can do is to supply ip interfaces to common ADC's to assist the user and to collaborate with adc vendors on new interface architectures.

    Note, its not so many years ago the ADC's got LVDS ports simplifying gnd separation. Also we now see adc's with built-in test pattern generators which are very useful to verify the timing and integrity of the board. I have yet to see an adc with JTAG test port features!

    I wonder when ADC's which fits seamlessly into an Altera SERDES port will appear?

    Would be nice though.