![background image](http://html1.mh-extra.com/html/embedian/smarc-t335-series/smarc-t335-series_hardware-design-manual_2399477036.webp)
SMARC T335x Carrier Board Hardware Design Guide, Document Revision 1.2
2.2.2.1. Gigabit Ethernet LAN Magnetics Modules
1000Base-T
Ethernet magnetics modules are similar to those designed
solely for
10/100Base-Tx
Ethernet, except that there are four
MDI
differential signal pairs instead of two.
1000Base-T magnetics modules have a center tap pin that is connected to
the reference voltage output '
GBE_CTREF
' of the
SMARC
module, which
biases the controller's output buffers. Magnetics with four center tap pins
may have better characteristics than those with one or two center tap pins.
The isolation magnetics can be integrated in a RJ45 jack, which also
provides activity and speed LED indicators. Alternatively, they can be
designed as discrete magnetics modules, which will be connected to a
pure RJ45 jack. The following table lists recommended magnetics
modules and RJ45 jacks for usage on a carrier board design.
1000Mbps Ethernet LAN Magnetics
Recommended Magnetics
Vendor
Part Number
Technology
Comments
Pulse
Engineering
H5007
10/100/1000BaseT
Discrete magnetics module
Pulse
Engineering
JK0-0036
10/100/1000BaseT
RJ45 jack with integrated
magnetics and activity LEDs
Bel Fuse
S558-5999-P3
10/100/1000BaseT
Discrete magnetics module
Pulse
JW0A1P01R-E
10/100/1000BaseT
RJ45 jack with integrated
magnetics and USB jacks
Foxconn
UB11123-J51
10/100/1000BaseT
RJ45 jack with integrated
magnetics and USB jacks