SD Interface¶
Signals¶
| Pin | Signal | type | I/O | Description |
| 36 | SD_CD | 3V3 | I | SD Card Detect – connected to a GPIO |
| 38 | SD_D0 | 3V3 | I/O | SD Data bidirectional signals |
| 37 | SD_D1 | |||
| 42 | SD_D2 | |||
| 41 | SD_D3 | |||
| 40 | SD_CMD | 3V3 | I/O | SD Command bidirectional signal |
| 39 | SD_CLK | 3V3 | O | SD Output Clock. |
The QS standard pinout provides one dedicated SD interface.
SD-Card example diagram¶
Either the use of the processor internal pullups or the use of pullups on the baseboard is possible.
SDIO Design Recommendations
| Parameter | MIN | TYP | MAX |
| Operating Speed (Ultra-High Speed SD, SDR104) | 208 MHz | ||
| Operating Speed (MMCplus, eMMC) | 52 MHz | ||
| Signal Trace Length | 10 cm | ||
| Data/Clock group skew (Ultra-High Speed SD, SDR104) | 20 ps | ||
| Data/Clock group skew (MMCplus, eMMC) | 100 ps | ||
| Trace Impedance | 50 Ω |
QS Standard Contact Group Index
| Pins | Function | Pins | Function | Pins | Function | Pins | Function |
|---|---|---|---|---|---|---|---|
| 1-4 | SPI | 5-10 | I2C | 11-14 | CAN | 15-18 | SAI |
| 19-35 | Ethernet | 36-42 | SD Interface | 43-48 | USB | 49-52 | Power Supply, Reset and Boot mode |
| 53-76 | 18-bit RGB Display Interface | 77-78 | Backlight and Display Control | 53-72 | Camera | 79-88 | MIPI DSI Display |
| 89-96 | UART | 97-100 | SPI | 1A,75A,76A,100A | PCIe | 25A,26A,50A,51A | USB3 Super Speed |