Datasheet

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DP83848T
1.7 10 Mb/s and 100 Mb/s PMD Interface
1.8 Special Connections
1.9 Power Supply Pins
Signal Name Type Pin # Description
TD-, TD+ I/O 14, 15 Differential common driver transmit output (PMD Output Pair).
These differential outputs are automatically configured to either
10BASE-T or 100BASE-TX signaling.
In Auto-MDIX mode of operation, this pair can be used as the Re-
ceive Input pair.
These pins require 3.3V bias for operation.
RD-, RD+ I/O 11, 12 Differential receive input (PMD Input Pair). These differential in-
puts are automatically configured to accept either 100BASE-TX
or 10BASE-T signaling.
In Auto-MDIX mode of operation, this pair can be used as the
Transmit Output pair.
These pins require 3.3V bias for operation.
Signal Name Type Pin # Description
RBIAS I 20 Bias Resistor Connection. A 4.87 kΩ 1% resistor should be con-
nected from RBIAS to GND.
PFBOUT O 19 Power Feedback Output. Parallel caps, 10µF (Tantalum pre-
ferred) and 0.1µF, should be placed close to the PFBOUT. Con-
nect this pin to PFBIN1 (pin 16) and PFBIN2 (pin 30). See
Section 5.4 for proper placement pin.
PFBIN1
PFBIN2
I16
30
Power Feedback Input. These pins are fed with power from
PFBOUT pin. A small capacitor of 0.1µF should be connected
close to each pin.
Note: Do not supply power to these pins other than from
PFBOUT.
RESERVED I/O 8,9,10 RESERVED: These pins must be left unconnected.
Signal Name Pin # Description
IOVDD33 1, 26 I/O 3.3V Supply
IOGND 40 I/O Ground
DGND 29 Digital Ground
AVDD33 18 Analog 3.3V Supply
AGND 13, 17 Analog Ground