DM9081FP DAVICOM [Davicom Semiconductor, Inc.], DM9081FP Datasheet - Page 12

• Manufacturer Part Number: DM9081FP
• Description: 10BASE-T Hub Controller
• Manufacturer: DAVICOM [Davicom Semiconductor, Inc.]

DM9081 Chip External Components
Figure 5 shows a typical twisted pair port external
components schematic diagram. The resistor used
should have a 1% tolerance to ensure compliance
with 10BASE-T networks. The filters and pulse
transformers are necessary devices that have a
major impact on the performance and compliance of
the 10BASE-T repeater ports. Specifically, the
transmitted waveforms are heavily influenced by the
filter characteristics, and the twisted pair receivers
employ several criteria to continuously monitor the
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Figure 5. Typical Single TP Port Using External Components
Figure 6. Typical Single AUI Port Using Components
incoming signals' amplitude and timing
characteristics to determine the necessity and the
time to assert the internal carrier sense. For these
reasons, it is crucial that the values of the resistors
and the tolerances of the external components
comply with given specifications. Several
manufacturers produce modules that combine the
functions of the transmit filters, receive filters, and
pulse transformers into one package.
10BASE-T Hub Controller
Version: DM9081-DS-F02
DM9081
February 02, 2001
Final