3 Replies Latest reply on May 8, 2017 2:08 PM by Intel Corporation

    Micro-SD IP4856CX25 (U1)




      I am trying to build up an expansion board for my project.   Your reference design is using the IP4856CX25/CZ chip.   It seems that there is no inventory on this chip anywhere.   See https://octopart.com/ip4856cx25%2Fcz-nxp+semiconductors-34971082 .  


      Do you have an alternate chip design that would be compatible with the current OS's?  





        • 1. Re: Micro-SD IP4856CX25 (U1)



          In my search for alternative to IP4856CX25, which btw has a 24 week lead time (available 10/17/17), the alternative chips are:


          1.  NXP NVT4857UKZ - Nothing available.

          2.  TI TXS0206  -   Quantity available on digikey


          Going with TXS0206 - Can you help me mapping the connections from the Joule to the Chip.   Here is a snap shot of the schematic from TI datasheet.  I am trying to map the expansion board connections to this chip but having problems with pin functionality.   I gave it a shot with text in red that maps to the expansion board schematic.    But I am very confused on DIR_0, DIR_1_3, DIR_CMD, SEL pins.   


          Appreciate any help someone can offer.







          • 2. Re: Micro-SD IP4856CX25 (U1)

            Accidently hit Correct Answer and it not answered.  How do I fix that?

            • 3. Re: Micro-SD IP4856CX25 (U1)
              Intel Corporation
              This message was posted on behalf of Intel Corporation

              Hi Don,

              Thanks for contacting us.

              Unfortunately, the custom boards are out of the scope of this technical support team. Nevertheless, the recommendation that I can give you is to check the datasheet of the IP4856CX25 (http://assets.nexperia.com/documents/data-sheet/IP4856CX25_C.pdf) to know exactly the function of each pin, and compare them with your chip's pins.

              It looks like that you have to connect the pin SDCARD_CMD to the CMDA pin of your chip. And about the pins that you are confused, DIR_0, DIR_1_3, DIR_CMD, it seems that they are used to determine if a command and data signals are transferred from the memory card to the host (card read mode) or from the host to the memory card (card write mode).

              I hope you find this information helpful.

              Leonardo R.