AR# 40279

ML605 - PCIe reset pull-up specification

Description

The ML605 PCIE reset signal (PCIE_PERST_B) has a 4.7 kilohm pull-up resistor to 3.3V. This gives a resulting current of 700 uA.

Does this violate thePCIE Card Electromechanical Specification for leakage current for this reset pin?

Solution

PCIE_PERST_B, the Integrated Endpoint block reset signal, is pulled up to 3.3V through a 4.7 kilohm resistor. According to the PCIE Card Electromechanical Specification, leakage current for the PCI PERST# pin should be in the range of -10 uA to +10 uA only.
If you are concerned about this setup, you can replace the pull-up resistor on your ML605 to a value that keeps the leakage current in the desirable range. A pull-up resistor of 392 kilohm, in a 0402 package, to 3.3Vshould ensure that the leakage current does not violate the specification.
AR# 40279
Date 12/15/2012
Status Active
Type General Article
Boards & Kits