Each VDDSHV[8:0], and VDDSHV[2:0]_WKUP can be configured as 1.8 V or 3.3 V. Figure 8-7 through Figure 8-10 illustrate different system configurations for the dual-voltage I/O supplies.

VDDSHV[8:0], and VDDSHV[2:0]_WKUP are the dual-voltage LVCMOS I/O supplies, while VDDS[8:0] are the dual-voltage LVCMOS I/O bias supplies. If any of the VDDSHV[8:0] or VDDSHV[2:0]_WKUP are configured for 3.3 V operation, the corresponding VDDS[8:0] or VDDS[2:0]_WKUP should be sourced from the internal I/O Bias LDO. When any of the VDDSHV[8:0] or VDDSHV[2:0]_WKUP are configured for 1.8 V operation, both VDDS[8:0] and VDDSHV[8:0] or VDDS[2:0]_WKUP and VDDSHV[2:0]_WKUP should be supplied from the same source.

Two I/O Bias LDOs are integrated on this device to share load current. The recommended load sharing is as follows:

• IOLDO0 : VDDS0, VDDS1, VDDS2, VDDS5, VDDS7, VDDS8
• IOLDO1 : VDDS3, VDDS4, VDDS6

Figure 8-7 shows all VDDSHV[8:0], and VDDSHV[2:0]_WKUP supplies configured for 3.3V operation.

Figure 8-7 All VDDSHV[8:0], and VDDSHV[2:0]_WKUP Supplies Configured for 3.3 V Operation

Figure 8-8 shows all VDDSHV[8:0] and VDDSHV[2:0]_WKUP supplies configured for 1.8 V operation.

Figure 8-8 All VDDSHV[8:0] and VDDSHV[2:0]_WKUP Supplies Configured for 1.8V Operation

Figure 8-9 shows a split configuration where VDDSHV[0, 1, 2, 5, 8] and VDDSHV0_WKUP are configured for 3.3 V operation, while VDDSHV[3, 4, 6, 7] and VDDSHV[2:1]_WKUP are configured for 1.8 V operation. Note the colors indicate rails that are tied to the same source.

Figure 8-9 VDDSHV[8:0] and VDDSHV[2:0]_WKUP Supplies Configured for Combination of 1.8 V or 3.3 V Operation

Figure 8-10through Figure 8-12 illustrates the system configuration when VDDSHV6 or VDDSHV7 is used as the MMCSD supply.

Figure 8-10 VDDSHV6 or VDDSHV7 Used as the MMCSD Supply for Fixed 1.8V IO

Figure 8-11 VDDSHV6 or VDDSHV7 Used as the MMCSD Supply for Fixed 3.3V IO

Figure 8-12 VDDSHV6 or VDDSHV7 Used as the MMCSD Supply for Dynamic 3.3V/1.8V IO