1 Reply Latest reply on Jan 4, 2020 7:47 AM by michaelkellett

    Evaluation Board for HMCAD1511 -- Interfacing with Spartan 7 SP 701 Evaluation Board

    arneldcollins

      Hi,

       

      I am beset with a range of problems with a new design I am starting, which is to interface a HMCAD 1511 ADC with a Spartan 7 SP 701 Evaluation Board. Hopefully someone will be be able to help me make some sense of this.

       

      I have read through the Xilinx APP, XAPP524. I propose using the HMCAD 1511 in single channel mode.  Single channel mode (Fs = 1000 MSPs) requires a bit rate clock of 500 MHZ DDR. Or does it? Is this any different from dual and quad modes where according to https://www.analog.com/media/en/technical-documentation/data-sheets/hmcad1511.pdf  Figures 4 through 6 it is obvious the bit clock remains the same while the input cock varies? From the point of view of interleaving then what advantage does this confer anyway if the bit clock rate reamins at 500 MHZ?As far as I can see it is just that more of the output channels have to be utilized as the sample clock increases but I would like to be enlightened.

       

      The other confusing item is that XAPP524 makes reference to 1 wire mode and 2 wire mode. Would the HMCAD 1511 not correspond to 1 wire mode since there is apparently no let in bit clock rate as sampling frequency is relaxed? According to the calculation of XZPP524, for 8 bit, 1000 Ms/s, 1 wire ADC, the DDR bit clock is 4,000 MHZ, making this topology not feasible for the 7 series FPGAs.

       

      Thanks if someone can share some insight into the above or describe if (s)he was successfully able to implement single channel mode with XAPP524 in a Spartan 7 FPGA.

       

      Arnel