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Cortina Systems LXT9785 and LXT9785E Advanced 8-Port 10/100 Mbps PHY Transceivers
LXT9785/LXT9785E
Datasheet
249241, Revision 11.0
16 April 2007
3.6 BGA15 Signal Descriptions
RxData0_S
RxData1_S
RxData2_S
RxData3_S
RxData4_S
RxData5_S
RxData6_S
RxData7_S
N3,
M2,
K2,
H3,
F2,
E3,
B4,
C5
O, TS
Receive Data - Ports 0-7.
These serial output streams provide data received from the
network. The LXT9785/LXT9785E drives the data out
synchronously to REFCLK.
SS-SMII Specific Signal Descriptions
TxSYNC
K1
I, ID
SS-SMII Transmit Synchronization.
The MAC must generate a TxSYNC pulse every 10 TxCLK
cycles to mark the start of TxData segments.
RxSYNC
E1
O, TS,
ID
SS-SMII Receive Synchronization.
The LXT9785/LXT9785E generates these pulses every 10
RxCLK cycles to mark the start of RxData segments for the
MAC.
TxCLK
J3
I, ID
SS-SMII Transmit Clock.
The MAC sources this 125 MHz clock as the timing
reference for TxData and TxSYNC.
RxCLK
G1
O, TS,
ID
SS-SMII Receive Clock.
The LXT9785/LXT9785E generates these clocks, based on
REFCLK, to provide a timing reference for RxData and
RxSYNC to the MAC.
RxData0_SS
RxData1_SS
RxData2_SS
RxData3_SS
RxData4_SS
RxData5_SS
RxData6_SS
RxData7_SS
M3,
M1,
J2,
H2,
F3,
C2,
A4,
C6
O, TS,
ID
Receive Data - Ports 0-7.
These serial output streams provide data received from the
network. The LXT9785/LXT9785E drives the data out
synchronously to REFCLK.
MDIO Control Interface Signal Descriptions
MDIO
N5
I/O, TS,
SL, IP
Management Data Input/Output.
Bidirectional serial data channel for communication
between the PHY and MAC or switch ASIC. Refer to
MDINT_L
P5
OD, TS,
SL,
IP
Management Data Interrupt.
When Register bit 18.1 = 1, an active Low output on this
Table 39
BGA15 Signal Descriptions (Sheet 2 of 7)
Symbol
BGA15 Ball
Designation
Type
Signal Description
1. Type Column Coding: I = Input, O = Output, OD = Open Drain output, ST = Schmitt Triggered input, TS =
Three-State-able output, SL = Slew-rate Limited output, IP = weak Internal Pull-up, ID = weak Internal pull-
Down.
2. Switched to TPIP/N Inputs when MDIX is not active (twisted-pair, non-crossover MDI mode).
3. Switched to TPOP/N Outputs when MDIX is not active (twisted-pair, non-crossover MDI mode).