Datasheet

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DP83848YB
1.8 10 Mb/s and 100 Mb/s PMD Interface
1.9 Special Connections
1.10 Power Supply Pins
Signal Name Type Pin # Description
TD-, TD+ I/O 16, 17 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 13, 14 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 24 Bias Resistor Connection. A 4.87 kΩ 1% resistor should be con-
nected from RBIAS to GND.
PFBOUT O 23 Power Feedback Output. Parallel caps, 10µ F (Tantalum pre-
ferred) and 0.1µF, should be placed close to the PFBOUT. Con-
nect this pin to PFBIN1 (pin 18) and PFBIN2 (pin 37). See
Section 5.4 for proper placement pin.
PFBIN1
PFBIN2
I 18
37
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 20, 21 RESERVED: These pins must be pulled-up through 2.2 kΩ resis-
tors to AVDD33 supply.
Signal Name Pin # Description
IOVDD33 32, 48 I/O 3.3V Supply
IOGND 35, 47 I/O Ground
DGND 36 Digital Ground
AVDD33 22 Analog 3.3V Supply
AGND 15, 19 Analog Ground
GNDPAD 49 Ground PAD