1 Reply Latest reply on Nov 26, 2019 8:35 PM by JayakrishnaT_76

    Maximum SPI trace length on CX3

    Kudo_4595136

      In our design, CX3 SPI interface was used to control peripheral, such as LCD or camera ISP.

      Distance between CX3 and peripheral is around 40cmSPI signal transfer via fine coaxial cable.

      I'm afraid if SPI can work properly with 40cm length.  Maybe it is ok. but I'm not sure.

      My question:

      1. The maximum signal length for CX3 SPI interface?

      2. Any solution to increase sign quality to make sure SPI signal can transfer longer distance? 

        • 1. Re: Maximum SPI trace length on CX3
          JayakrishnaT_76

          Hello,

           

          We do not have an exact value for the maximum signal length for CX3 SPI interface. This is because it depends on many factors such as cable,driver circuit, receiver circuit, frequency,signal levels etc.

          For increasing the signal quality, please try the following suggestions:

          1.Decrease the frequency.

          2.Do length matching between clock and data lines.

          3.Do impedance Matching.

           

          Also, make sure that the SPI Timing Parameters that are mentioned in page 42 of FX3 datasheet is met properly. The link to FX3 datasheet is given below:

          https://www.cypress.com/file/140296/download  

           

          Best Regards,

          Jayakrishna