DP83959 datasheet(6/38 Pages) NSC

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4.0

Pin Descriptions (Continued)

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The values of the resistor/capacitor parallel source imped-

ance matching networks connected to each of the

10BASE-T transmit outputs will depend upon PCB layout

factors (such as track length, width, route etc.) and will have

to be determined for each design. Preliminary laboratory

work suggests that values of 13.5

Ω and 820 pF are appro-

priate in order to meet IEEE 802.3 speciﬁcations and EMI

requirements - these values should be taken as a starting

point for investigation. Refer to Figure 9.

Signal Name

Type

Pin #

Description

TX1+

TPO

134, 135 Port 1 Transmit: 10BASE-T transmitter output - requires a series source

impedance matching network consisting of a resistor and capacitor in parallel. The

values of these components will be application speciﬁc.

RX1+

TPI

138, 139 Port 1 Receive: 10BASE-T receiver input - requires a 50

Ω receive termination.

TX2+

TPO

132, 133 Port 2 Transmit: 10BASE-T transmitter output - requires a series source

impedance matching network consisting of a resistor and capacitor in parallel. The

values of these components will be application speciﬁc.

RX2+

TPI

128, 129 Port 2 Receive: 10BASE-T receiver input - requires a 50

Ω receive termination.

TX3+

TPO

122, 123 Port 3 Transmit: 10BASE-T transmitter output - requires a series source

impedance matching network consisting of a resistor and capacitor in parallel. The

values of these components will be application speciﬁc.

RX3+

TPI

126, 127 Port 3 Receive: 10BASE-T receiver input - requires a 50

Ω receive termination.

TX4+

TPO

117, 118 Port 4 Transmit: 10BASE-T transmitter output - requires a series source

impedance matching network consisting of a resistor and capacitor in parallel. The

values of these components will be application speciﬁc.

RX4+

TPI

113, 114 Port 4 Receive: 10BASE-T receiver input - requires a 50

Ω receive termination.

TX5+

TPO

95, 96

Port 5 Transmit: 10BASE-T transmitter output - requires a series source imped-

ance matching network consisting of a resistor and capacitor in parallel. The values

of these components will be application specific.

RX5+

TPI

99, 100

Port 5 Receive: 10BASE-T receiver input - requires a 50

Ω receive termination.

TX6+

TPO

93, 94

Port 6 Transmit: 10BASE-T transmitter output - requires a series source imped-

ance matching network consisting of a resistor and capacitor in parallel. The values

of these components will be application specific.

RX6+

TPI

89, 90

Port 6 Receive: 10BASE-T receiver input - requires a 50

Ω receive termination.

TX7+

TPO

83, 84

Port 7 Transmit: 10BASE-T transmitter output - requires a series source imped-

ance matching network consisting of a resistor and capacitor in parallel. The values

of these components will be application specific.

RX7+

TPI

87, 88

Port 7 Receive: 10BASE-T receiver input - requires a 50

Ω receive termination.

TX8+

TPO

78, 79

Port 8 Transmit: 10BASE-T transmitter output - requires a series source imped-

ance matching network consisting of a resistor and capacitor in parallel. The values

of these components will be application specific.

RX8+

TPI

74, 75

Port 8 Receive: 10BASE-T receiver input - requires a 50

Ω receive termination.

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