Datasheet

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DP83846A
1.2 10 Mb/s and 100 Mb/s PMD Interface
1.3 Clock Interface
1.4 Special Connections
RXD[3]
RXD[2]
RXD[1]
RXD[0]
O, PU/PD 38, 39, 40, 41 RECEIVE DATA: Nibble wide receive data (synchronous to corre-
sponding RX_CLK, 25 MHz for 100BASE-TX mode, 2.5 MHz for
10BASE-T nibble mode). Data is driven on the falling edge of
RX_CLK. RXD[2] has an internal pulldown resistor. The remaining
RXD pins have pullups.
RX_ER/PAUSE_EN
S, O, PU 46 RECEIVE ERROR: Asserted high to indicate that an invalid symbol
has been detected within a received packet in 100BASE-TX mode.
RX_DV O 44 RECEIVE DATA VALID: Asserted high to indicate that valid data is
present on the corresponding RXD[3:0] for nibble mode. Data is driv-
en on the falling edge of the corresponding RX_CLK.
Signal Name Type LQFP Pin # Description
Signal Name Type LQFP Pin # Description
TD+, TD- O 16, 17 Differential common driver transmit output. These differential out-
puts are configurable to either 10BASE-T or 100BASE-TX signaling.
The DP83846A will automatically configure the common driver out-
puts for the proper signal type as a result of either forced configura-
tion or Auto-Negotiation.
RD-, RD+ I 10, 11 Differential receive input. These differential inputs can be configured
to accept either 100BASE-TX or 10BASE-T signaling.
The DP83846A will automatically configure the receive inputs to ac-
cept the proper signal type as a result of either forced configuration
or Auto-Negotiation.
Signal Name Type LQFP Pin # Description
X1 I 67 REFERENCE CLOCK INPUT 25 MHz: This pin is the primary
clock reference input for the DP83846A and must be connected to
a 25 MHz 0.005% (±50 ppm) clock source. The DP83846A sup-
ports CMOS-level oscillator sources.
X2 O 66 REFERENCE CLOCK OUTPUT 25 MHz: This pin is the primary
clock reference output.
Signal Name Type LQFP Pin # Description
RBIAS I 3 Bias Resistor Connection. A 9.31 kΩ 1% resistor should be connect-
ed from RBIAS to ANA_GND.
RESERVED I/O 1, 5, 8, 20,
21, 22, 47,
63, 68, 69,
70, 71, 74,
75, 77, 78,
80
RESERVED: These pins must be left unconnected.
Obsolete