[This Figure, callout 6]
The ZCU111 board includes a secure digital input/output (SDIO) interface to provide access to general purpose non-volatile SDIO memory cards and devices. Information for the SD I/O card specification can be found at the SanDisk Corporation [Ref 17] or SD Association [Ref 18] websites. The ZCU111 SD card interface supports the SD1_LS configuration boot mode documented in the Zynq UltraScale+ Device Technical Reference Manual (UG1085) [Ref 3].
The SDIO signals are connected to XCZU28DR RFSoC PS bank 501, which has its VCCMIO set to 1.8V. The six SD interface nets MIOxx_SDIO_DAT[0:3], MIO50_SDIO_CMD, and MIO51_SDAIO_CLK each have a series 30Ω resistor at the bank 501 source. An NXP IP4856CX25 SD 3.0-compliant voltage level-translator U107 is present between the XCZU28DR RFSoC and the SD card connector (J100). The NXP IP4856CX25 U107 device provides SD3.0 capability with SDR104 performance.
This Figure shows the connections of the SD card interface on the ZCU111 board.
The NXP SD3.0 level shifter is mounted on an Aries adapter board that has the pin mapping shown in Table: IP4856CX25 U107 Adapter Pin-Out.
The connections between the SD NXP IP4856CX25 (U107) level-shifter and the XCZU28DR RFSoC PS bank 501 are referenced in Xilinx Design Constraints.