Table 6-6 and Figure 6-6 describes the device power-down sequencing.
Note: All power rails must be turned off and
decay below 300mV before initiating a new power-up sequence anytime a power rail drops below
the minimum value defined in Recommended Operating Conditions.
Table 6-6 Power-Down Sequencing – Supply / Signal
Assignments See: Figure 6-6
| WAVEFORM |
SUPPLY /
SIGNAL NAME |
| A |
VSYS,
VMON_VSYS |
| B |
VDDSHV_MCU(1), VDDSHV0(1), VDDSHV1(1), VDDSHV2(1), VDDSHV3(1), VDDSHV4(1),VDDA_3P3_USB0, VMON_3P3_SOC, VMON_3P3_MCU |
| C |
VDDSHV_MCU(2), VDDSHV0(2), VDDSHV1(2), VDDSHV2(2), VDDSHV3(2), VDDSHV4(2), VDDA_MCU, VDDS_OSC, VDDA_ADC0, VDDA_PLL0, VDDA_PLL1, VDDA_PLL2,
VDDA_1P8_SERDES0, VDDA_1P8_USB0, VMON_1P8_SOC, VMON_1P8_MCU, VDDA_TEMP0, VDDA_TEMP1,
VDDS_MMC0 |
| D |
VDDA_3P3_SDIO(3)(4), VDDSHV5(3) |
| E |
VDDS_DDR,
VDDS_DDR_C |
| F |
VDD_CORE(5)(7) |
| G |
VDD_CORE(6)(7), VDDA_0P85_USB0, VDDA_0P85_SERDES0, VDDA_0P85_SERDES0_C, VDD_MMC0, VDDA_DLL_MMC0,
VDDR_CORE(7) |
| H |
VPP |
| I |
MCU_PORz |
| J |
MCU_OSC0_XI,
MCU_OSC0_XO |
(1) VDDSHV_MCU and VDDSHVx [x=0-4] when operating at 3.3V.
(2) VDDSHV_MCU and VDDSHVx [x=0-4] when operating at 1.8V.
(3) VDDA_3P3_SDIO was designed to support
power-up or power-down without any dependency on other power rails. VDDSHV5 is a dual
voltage IO supply that was designed to support power-up, power-down, or dynamic voltage
change without any dependency on other power rails. This capability is required to support
UHS-I SD Cards.
(4) VDDA_3P3_SDIO is the 3.3V power rail for the internal SDIO_LDO. This power rail must be
sourced from the same 3.3V power supply that provides power to a UHS-I SD Card connected
to MMC1, which allows the MMC1 IOs and the SD Card IOs to power-up and power-down at the
same time when the SD Card power supply is powered off to reset the SD Card. For this use
case the SDIO_LDO output (CAP_VDDSHV_MMC1) is used to power the VDDSHV5 IO power rail,
which will ramp-up and ramp-down along with the VDDA_3P3_SDIO power rail.
(5) VDD_CORE when operating at 0.75V.
(6) VDD_CORE when operating at 0.85V.
(7) The potential applied to VDDR_CORE must
never be greater than the potential applied to VDD_CORE + 0.18V during power-up or
power-down. This requires VDD_CORE to ramp up before and ramp down after VDDR_CORE when
VDD_CORE is operating at 0.75V. VDD_CORE does not have any ramp requirements beyond the
one defined for VDDR_CORE.VDD_CORE and VDDR_CORE are
expected to be powered by the same source so they ramp together when VDD_CORE is operating
at 0.85V.