Datasheet

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DP83849C
1.7 10 Mb/s and 100 Mb/s PMD Interface
LED_CFG_A
(CRS_A/CRS_DV_A)
LED_CFG_B
(CRS_B/CRS_DV_B)
S, O, PU 1
61
LED CONFIGURATION: This strapping option determines the
mode of operation of the LED pins. Default is Mode 1. Mode 1 and
Mode 2 can be controlled via the strap option. All modes are con
-
figurable via register access.
See Tabl e 3 on page 20 for LED Mode Selection.
MDIX_EN_A (RX_ER_A)
MDIX_EN_B (RX_ER_B)
S, O, PU 2
60
MDIX ENABLE: Default is to enable MDIX. This strapping option
disables Auto-MDIX. An external pull-down will disable Auto-
MDIX mode.
ED_EN_A (RXD3_A)
ED_EN_B (RXD3_B)
S, O, PD 9
53
Energy Detect ENABLE: Default is to disable Energy Detect
mode. This strapping option enables Energy Detect mode for the
port. In Energy Detect mode, the device will initially be in a low-
power state until detecting activity on the wire. An external pull-up
will enable Energy Detect mode.
CLK2MAC_DIS (RXD2_A) S, O, PD 8 Clock to MAC Disable: This strapping option disables (floats) the
CLK2MAC pin. Default is to enable CLK2MAC output. An external
pullup will disable (float) the CLK2MAC pin. If the system does not
require the CLK2MAC signal, the CLK2MAC output should be dis
-
abled via this strap option.
Signal Name Type Pin # Description
Signal Name Type Pin # Description
TPTDM_A
TPTDP_A
TPTDM_B
TPTDP_B
I/O 26
27
36
35
10BASE-T or 100BASE-TX 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.
These pins require 3.3V bias for operation.
TPRDM_A
TPRDP_A
TPRDM_B
TPRDP_B
I/O 23
24
39
38
10BASE-T or 100BASE-TX 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.
These pins require 3.3V bias for operation.