SPRUJ51A June 2023 – November 2025
The I/O Expanders are used in the AM62x-Low Power SK EVM are a 24-Bit I2C based I/O Expander which is used for daughter card plug-in detection and for generating resets and enable signals to various peripheral devices connected to it. The SoC_I2C1 bus of the AM62X 17x17 SoC is used to interface with the I/O Expanders. The I2C device address of the I/O Expander is 0x21 and 0x23. See the tables below for the list of signals being controlled by the Expanders.
| IO EXPANDER - 01 | |||
|---|---|---|---|
| Pin no | SIGNAL | DIRECTION | DEVICE |
| P11 | GPIO_EMMC_RSTN | OUTPUT | eMMC Reset control GPIO |
| P01 | GPIO_CPSW1_RST | OUTPUT | CPSW Ethernet PHY-1 Reset Control GPIO |
| P00 | GPIO_CPSW2_RST | OUTPUT | CPSW Ethernet PHY-2 Reset Control GPIO |
| P03 | MMC1_SD_EN | OUTPUT | SD Card Load Switch Enable |
| P04 | VPP_LDO_EN | OUTPUT | SOC eFuse Voltage(VPP=1.8V) Regulator Enable |
| P05 | EXP_PS_3V3_EN | OUTPUT | EXP CONN 3.3V Power Switch Enable |
| P06 | EXP_PS_5V0_EN | OUTPUT | EXP CONN 5V Power Switch Enable |
| P10 | GPIO_AUD_RSTN | OUTPUT | Audio Codec Reset Control GPIO |
| P07 | EXP_HAT_DETECT | INPUT | EXP CONN HAT Board Detection |
| P02 | PRU_DETECT | INPUT | PRU Board Detection |
| P12 | UART1_FET_BUF_EN | OUTPUT | SOC UART1 Mux Select |
| P13 | BT_UART_WAKE_SOC | INPUT | BT UART WKUP Signal |
| P14 | GPIO_HDMI_RSTN | OUTPUT | HDMI Transmitter Reset Control GPIO |
| P15 | CSI_GPIO0 | NA | Raspberry Pi Camera CSI0 GPIO1 |
| P16 | CSI_GPIO1 | NA | Raspberry Pi Camera CSI0 GPIO2 |
| P17 | GPIO_OLDI_INT | INPUT | OLDI Interrupt |
| P20 | HDMI_INTN | INPUT | HDMI Interrupt |
| P21 | TEST_GPIO2 | INPUT | TEST GPIO2 from Test Automation Connector |
| P22 | MCASP1_FET_EN | OUTPUT | MCASP1 Enable and Direction Control |
| P23 | MCASP1_BUF_BT_EN | OUTPUT | |
| P24 | MCASP1_FET_SEL | OUTPUT | |
| P25 | UART1_FET_SEL | OUTPUT | |
| P27 | IO_EXP_TEST_LED | OUTPUT | User Test LED 2 |
| IO EXPANDER - 02 | |||
|---|---|---|---|
| Pin no | SIGNAL | DIRECTION | DEVICE |
| P20 | SPI0_FET_SEL | OUTPUT | SoC SPI0 MUX Selection |
| P21 | SPI0_FET_OE | OUTPUT | SoC SPI0 MUX Enable |
| P22 | GPIO_OLDI_RSTn | OUTPUT | OLDI Reset |
| P23 | PRU_3V3_EN | OUTPUT | PRU Power Switch Enable |
| P26 | CSI_VLDO_SEL | OUTPUT | CSI Regulator Enable (VCC_CSI_IO) |
| P27 | SOC_WLAN_SDIO_RST | OUTPUT | WLAN Reset control GPIO |
| P10 | WL_LT_EN | OUTPUT | Wilink Enable |
| P11 | CSI_RSTZ | OUTPUT | CSI Reset control GPIO |