Table 7. i.MX8 QM power/decoupling recommendations (continued)
Checkbox Recommendation Explanation/Supplemental Recommendation
• VDD_HDMI_RX0_LDO0_1P0_CAP
• VDD_HDMI_RX0_LDO1_1P0_CAP
• VDD_PCIE_LDO_1P0_CAP
others should be connected to the i.MX8 QM balls, as
shown below:
• VDD_HDMI_TX0_LDO_1P0_CAP
1. VDD_HDMI_TX0_1P0
• VDD_PCIE_LDO_1P0_CAP
1. VDD_PCIE0_1P0
2. VDD_PCIE1_1P0
3. VDD_PCIE_SATA0_1P0
4. The VDD_USB_SS3_LDO_1P0_CAP internal
LDO should be decoupled with three 2.2 µF caps.
Place two capacitors underneath the BGA package as
close as possible to the LDO output (desired trace length
< 50 mils). The other cap should be placed on the back
side as close as possible to the other two capacitors.
This LDO output should only drive:
1. VDD_USB_OTG1_1P0
2. VDD_USB_OTG2_1P0
Table 8. i.MX8 QXP power/decoupling recommendations
Checkbox Recommendation Explanation/Supplemental Recommendation
1. Comply with the power-up sequence
guidelines, as described in the datasheet to
guarantee reliable operation of the device.
Any deviation from these sequences may result in the
following situations:
• Excessive current during the power-up phase.
• Prevention of the device from booting.
• Irreversible damage to the processor (worst case
scenario).
2. Maximum ripple voltage requirements.
A common requirement for the ripple noise should be less
than 5 % peak-to-peak of the supply voltage nominal value.
3. The VDD_PCIE_LDO_1P0_CAP internal
LDO should be decoupled with a 2.2 µF cap
and a 0.22 µF cap.
Place the 0.22 μF capacitor underneath the BGA package as
close as possible to the LDO output (desired trace length <
50 mils).
4. The VDD_USB_SS3_LDO_1P0_CAP
internal LDO should be decoupled with a 2.2
µF cap and two 0.22 µF caps.
Place the 0.22 μF capacitors underneath the BGA
package as close as possible to the LDO output (desired
trace length < 50 mils). This LDO output should only
drive VDD_USB_OTG1_1P0.
See the i.MX8QM LPDDR4 MEK layout for the recommended capacitor placement.
NXP Semiconductors
i.MX8 QM and QXP design checklist
i.MX8 QM / i.MX8 QXP Hardware Developer’s Guide, Rev. 2.4p, 06/2021
User's Guide 10 / 89
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