2 Replies Latest reply on Jul 13, 2016 5:07 AM by userc_39905

    Decoupling and unused pins

      for the CYD36S72V18, what are your recommendations for power supply decoupling and for handling unused pins?





        • 1. Re: Decoupling and unused pins

          Not sure if you have had a look at our design guide for FullFlex devices - http://www.cypress.com/file/151216/download


          It has the status of each of the pins which are not in use. 


          For power supply- we recommend to have a decoupling capcitor for every pin and a bulk capacitor for every set of power rails. If there is a space constraint, we recommend to do a power integrity analysis to get the optimal value of bulk/decoupling capacitors array.

          • 2. Re: Decoupling and unused pins

            Hi Ajai,


            Thanks for your help.  I had found the design guide.


            I guess I did not ask my first question very well.  Let's say I am using the left data ports as inputs only and that I need only 70 of the 72 bits.  What should I do with the two unused bits - tie them high via a resistor, tie them to ground or leave them open?


            With respect to decoupling, do you recommend any particular value capacitors?