DM9010EP datasheet(54/62 Pages) DAVICOM

54 / 62 page

DM9010

Single Chip Ethernet Controller with General Processor Interface

Preliminary

Version: DM9010-17--DS-P04

Jan. 18, 2006

11. Application Notes

11.1 Network Interface Signal Routing

Place the transformer as close as possible to the RJ-45

connector. Place all the 50Ω resistors as close as possible

to the DM9010 RXI± and TXO± pins. Traces routed from

RXI± and TXO± to the transformer should run in close pairs

directly to the transformer. The designer should be careful

not to cross the transmit and receive pairs. As always, vias

should be avoided as much as possible. The network

interface should be void of any signals other than the TXO±

and RXI± pairs between the RJ-45 to the transformer and

the transformer to the DM9010.. There should be no

power or ground planes in the area under the network side

of the transformer to include the area under the RJ-45

connector. (Refer to Figure 11-4 and 11-5) Keep chassis

ground away from all active signals. The RJ-45 connector

and any unused pins should be tied to chassis ground

through a resistor divider network and a 2KV bypass

capacitor.

The Band Gap resistor should be placed as physically close

as pins 25 and 26 as possible (refer to Figure 11-1 and

11-2). The designer should not run any high-speed signal

near the Band Gap resistor placement.

11.2 10Base-T/100Base-TX HP Auto-MDIX Application

Figure 11-1 HP Auto-MDIX Application

DM9010EP Datasheet(PDF) 54 Page - Davicom Semiconductor, Inc.