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2.10.2.4 eSPI Devices
At the time of this writing, the use case and design rules for eSPI are still being developed.
Designers of Modules and Carriers are provided with the following guidance:
The maximum trace length for Carrier routed eSPI traces
shall not
exceed 4.5”.
Carrier routed ESPI traces
shall
be routed at 50 Ohms.
Carrier routed SPI traces
shall
have 5 mil via to via clearance, 4 mil trace to via clearance, and 10 mil
clearance to any other traces.
The Carrier
shall
have a 33 Ohm series termination between 0.5” and 1” of the target device on the
ESPI_CK signal.
The Carrier
shall
have a 33 Ohm series termination between 0.5” and 1” of the target device on the
ESPI_IO_[0..3] signals.
The Carrier
shall
length match ESPI_CK and ESPI_IO_[0..3] within 250mils.
The Carrier
shall
length match eSPI_CK and ESPI_CS within 100mils.