drawn does not exceeds 10mA. The ETH1_ACT signal is used as reference for the ETH1_MDI3-
signal in the MXM3 connector, a strapping capacitor of 1nF should be placed to GND close to the
MXM3 connector.
2.4.2.1 Gigabit Ethernet Schematic Example (Integrated Magnetics)
All currently available Toradex Apalis modules do not require a center tap voltage. Only 100nF
capacitors are required on the center tap pins of the magnetics. Connecting the center tap signals
together can degrade the signal quality and is therefore not recommended. However, in order to
be compatible with any future modules which require a center tap voltage, we still recommend to
add the circuit below with non-assembled zero ohm resistors.
Figure 16: Gigabit Ethernet with integrated magnetics reference schematic
2.4.2.2 Gigabit Ethernet Schematic Example (Discrete Magnetics)
If discrete magnetics are used instead of a RJ-45 Ethernet jack with integrated magnetics, special
care has to be taken to route the signals between the magnetics and the jack. These signals are
required to be high-voltage isolated from the other signals. It is therefore necessary to place a
dedicated ground plane under these signals which has a minimum separation of 2mm from every
other signal and plane. Additionally, a separate shield ground for the LAN device is needed. Try to
place the magnetics as close as possible to the Ethernet jack. This reduces the length of the signal
traces between the magnetics and jack.
To Next Page
Loading...
