- Assert
GRST and
PERST to the device.
- Apply 1.5-V and 3.3-V voltages. The order of the 1.5-V or 3.3-V supplies coming up is not important, as long as the supplies never exceed more than 2.6V from each other.
- Apply a stable PCIe reference clock.
- To meet PCIe specification requirements,
PERST cannot be deasserted until the following two delay requirements are satisfied:
- Wait a minimum of 100 μs after applying a stable PCIe reference clock. The 100 μs limit satisfies the requirement for stable device clocks by the deassertion of
PERST.
- Wait a minimum of 100 ms after applying power. The 100 ms limit satisfies the requirement for stable power by the deassertion of
PERST.
See the power-up sequencing diagram in Figure 10-2.