User's Manual l TQMa8XxS UM 0101 l © 2022, TQ-Systems GmbH
Page 22
3.3.5
SDIO card interface
The SDIO Card interface is provided by the USDHC1 interface of the i.MX 8X. In contrast to the TQMa8Xx, the CPU supply pin
"VDD_USDHC1_VSELECT_1P8_3P3" is supplied with 3.3V instead of 1.8V. Thus the otherwise necessary level converters for the
signals SDIO_CD#, SDIO_WP and SDIO_PWR_EN can be omitted. The SDIO_PWR_EN signal is used to switch on the SD supply
voltage on the carrier. To be able to boot from SD card, a high level must be applied to the signal at boot time. However,
SDIO_PWR_EN is low by default.
i.MX 8X
SMARC-Pins
USDHC1_CD#
SDIO_CMD
SDIO_D[3:0]
SDIO_CD#
USDHC1_DATA[3:0]
SDIO_CK
USDHC1_CLK
USDHC1_CMD
USDHC1_WP
SDIO_WP
USDHC1_RESET#
SDIO_PWR_EN
V_3V3
V_3V3
V_3V3
Figure 16: Block diagram SDIO
3.3.6
Audio
The I2S0 interface at the SMARC pins is provided by a part of the SAI1 interface as well as by the FLEXCAN1 interface of the i.MX
8X. The AUDIO_MCLK signal is connected to MCLK_OUT0 of the CPU.
i.MX 8X
SMARC-Pins
SAI1_RXFS
I2S0_CK
I2S0_SDIN
I2S0_LRCK
FLEXCAN1_TX
I2S0_SDOUT
FLEXCAN1_RX
SAI1_RXC
AUDIO_MCK
MCLK_OUT0
Figure 17: Block diagram Audio
