Datasheet

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DP83849ID
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
TPTDM_A/FXTDM_A
TPTDP_A/FXTDP_A
TPTDM_B/FXTDM_B
TPTDP_B/FXTDP_B
I/O 26
27
36
35
10BASE-T or 100BASE-TX or 100BASE-FX Transmit Data
In 10BASE-T or 100BASE-TX: Differential common driver trans-
mit output (PMD Output Pair). These differential outputs are auto-
matically 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.
In 100BASE-FX mode, this pair becomes the 100BASE-FX
Transmit pair.
These pins require 3.3V bias for operation.
TPRDM_A/FXRDM_A
TPRDP_A/FXRDP_A
TPRDM_B/FXRDM_B
TPRDP_B/FXRDP_B
I/O 23
24
39
38
10BASE-T or 100BASE-TX or 100BASE-FX Receive Data
In 10BASE-T or 100BASE-TX: Differential receive input (PMD In-
put Pair). These differential inputs 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.
In 100BASE-FX mode, this pair becomes the 100BASE-FX
Receive pair.
These pins require 3.3V bias for operation.
FXSD_A
(LED_SPEED_A/AN1_A)
FXSD_B
(LED_SPEED_B/AN1_B)
I 20
42
FX Signal Detect: This pin provides the Signal Detect input for
100BASE-FX mode.
Signal Name Type Pin # Description
RBIAS I 32 Bias Resistor Connection. A 4.87 kΩ 1% resistor should be con-
nected from RBIAS to GND.
PFBOUT O 31 Power Feedback Output. Parallel caps, 10µ F and 0.1µF, s ho ul d
be placed close to the PFBOUT. Connect this pin to PFBIN1 (pin
13), PFBIN2 (pin 27), PFBIN3 (pin35), PFBIN4 (pin 49). See
Section 5.5 for proper placement pin.
PFBIN1
PFBIN2
PFBIN3
PFBIN4
I 7
28
34
54
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.
Signal Name Pin # Description
IOVDD1, IOVDD2, IOVDD3,
IOVDD4
11,51,65,78 I/O 3.3V Supply
IOGND1, IOGND2,
IOGND3, IOGND4
10,52,64,77 I/O Ground
COREGND1, COREGND2 6,55 Core Ground
CDGND1, CDGND2 25,37 CD Ground
ANA33VDD 30 Analog 3.3V Supply
ANAGND1, ANAGND2,
ANAGND3, ANAGND4
22,29,33,40 Analog Ground