GE Mini COM Express 10 Hardware Reference Manual page 39

USB_0_1_OC#, USB_2_3_
OC#, USB_4_5_OC#, and
USB_6_7_OC# signals are
used to flag a USB
over-current situation.
Configuration
For public disclosure
5.1.1.2 Carrier Board Termination
The following signals require carrier board termination for proper operation. If the signals
and features are not used, no carrier board termination is required and the pins may be left
open.
Ethernet External Ethernet magnetics are implemented on the carrier board.
LVDS The LVDS flat panel differential pairs (LVDS_A/B[0:3] ±, LVDS_A/B_CK ±)
should have 100 [ termination across the pairs at the destination. This may be on the
carrier board if the carrier board implements an LVDS de-serializer on-board.
USB
No termination is required on USB pairs. A common mode choke and ESD
protection is advisable if USB pairs on the carrier board are routed to a connector for use
with an external cable. Carrier board USB overcurrent monitors may pull the USB_
[0,2,4,6]_[1,3,5,7]_OC# l lines to GND with open drain drivers to indicate that the
monitorʹs current limit has been exceeded. Do not pull up these lines to 3.3 V on the
carrier board; this is done on the module.
PCI Express
At the module, the PCI Express transmit signals have ac coupling
capacitors. For the carrier PCIe transmit lines (receive at the module), ac coupling must
be located at the carrier.
DDI Ports
Carrier-based terminations are dependent on the video interface supported
by the module, as follows:
• DDI0 is an interface for Display Port or TMDS (DVI/HDMI)
• DC blocking capacitors are placed on the carrier for the DDI0_PAIR[0:3] signals.
• The carrier includes a blocking Field Effect Transistor (FET) on DDI[n]_HPD to
prevent back-drive current from damaging the module.
GFK-2896 Hardware Reference Manual 39