Part Number: TXB0106
We are facing sd card compatibility issues with the TXB0106.
Here is the initial interface configuration. The task is to boot from any SDcards. For the initial configuration (hope u can see picture that I tried to insert, 51K pullUps to 3.3V on the interface to the sd card) only the following card from our current sd card stock is working: Kingston 64GB micro sdxc I U3
The following sd card do not work with this electrical configuration:
- SanDisk Extreme 32GB micro sdhc I V30 U3- Kingston 16GB micro sdhc I U1 industrial
- Samsung 32 EVO Plus micro sdhc I U1- Samsung 32 PRO Plus micro sdhc I U3
After changing values for the pullUps, checking the signals and the supply voltages we end up with the following el. config where all the cards work but the Samsung cards:
So the PullUps are at 1.8V and 100K now on the 3.3V side. As mentioned the following card do work now:
- Kingston 64GB micro sdxc I U3
The follwing Samsung cards still don't work:
It's quite hard to find datasheets or any spec about the exact IO configurations of the SD cards. It looks like the Samsung cards do have a stronger Pull-Up on the cmd line for the initialization period and therefore "overwriting" the TXB0106 thus never receiving the cmd issued by the host (the Intel A10AS057 in our case). But this is just a guess... Any idea would be very appreciated!
Thanks in advance.
We are glad that we were able to resolve this issue, and will now proceed to close this thread.
If you have further questions related to this thread, you may click "Ask a related question" below. The newly created question will be automatically linked to this question.
In reply to Emrys Maier:
Thanks for your reply and yes after sending my post I saw that the pictures were not added. So above is my next trial to add the pictures...
The PullUps were added for the SDcard not for the TXB0106 and their values were chosen according to the recommendations of the TXB0106 datasheet (>50K) . In the meanwhile, we think to understand that even for the SDcard a pullUp on the CMD line only would be sufficient. The data lines seem to be push-pull from the beginning and the cmd lines changes from open-drain in the initialization period of the Sdcard to push-pull after it changes to SD mode.
Any further input or correction/support of the above is very welcome.
In reply to Benjamin von Niederhaeusern:
The TXB0106 is not disabled in our application. Are you suggesting to remove the 100K pullUps as they are not required by the TXB0106 nor by the SDcard? The signal on the CMD line look the following when a Samsung SD card is inserted:
The signal level on both sides look correct when one of the other card types (mentioned above) is inserted.
I'm aware that other devices like the TXS0108, TXS0206 or a LSF type may be the fast fix here and having all the cards working. But it would be nice to understand what exactly happens and why some cards do work and the Samsung cards don't work in this particular setup. What is / what could be the difference here?
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.