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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
3.4 BGA23 Signal Descriptions
3.4.2
Signal Descriptions – RMII, SMII, and SS-SMII Configurations
Table 24
RMII Signal Descriptions – BGA23 (Sheet 1 of 3)
Ball/Pin
Designation
Symbol
Type1
Signal Description2,3
BGA23
PQFP
E6,
E12
44
6
REFCLK0
REFCLK1
I
Reference Clock.
50 MHz RMII reference clock is always required. RMII
inputs are sampled on the rising edge of REFCLK,
RMII outputs are sourced on the falling edge.
E2,
F4
61
62
TxData0_0
TxData0_1
I, ID
Transmit Data - Port 0.
Inputs containing 2-bit parallel di-bits to be transmitted
from port 0 are clocked in synchronously to REFCLK.
C3,
D4
52
53
TxData1_0
TxData1_1
I, ID
Transmit Data - Port 1.
Inputs containing 2-bit parallel di-bits to be transmitted
from port 1 are clocked in synchronously to REFCLK
B5
A4
42
43
TxData2_0
TxData2_1
I, ID
Transmit Data - Port 2.
Inputs containing 2-bit parallel di-bits to be transmitted
from port 2 are clocked in synchronously to REFCLK.
D8,
A6
34
35
TxData3_0
TxData3_1
I, ID
Transmit Data - Port 3.
Inputs containing 2-bit parallel di-bits to be transmitted
from port 3 are clocked in synchronously to REFCLK.
A11,
C10
22
23
TxData4_0
TxData4_1
I, ID
Transmit Data - Port 4.
Inputs containing 2-bit parallel di-bits to be transmitted
from port 4 are clocked in synchronously to REFCLK.
B13,
D11
13
14
TxData5_0
TxData5_1
I, ID
Transmit Data - Port 5.
Inputs containing 2-bit parallel di-bits to be transmitted
from port 5 are clocked in synchronously to REFCLK.
D13,
A16
4
5
TxData6_0
TxData6_1
I, ID
Transmit Data - Port 6.
Inputs containing 2-bit parallel di-bits to be transmitted
from port 6 are clocked in synchronously to REFCLK.
E14,
C16
203
204
TxData7_0
TxData7_1
I, ID
Transmit Data - Port 7.
Inputs containing 2-bit parallel di-bits to be transmitted
from port 7 are clocked in synchronously to REFCLK.
E3,
B2,
C6,
A7,
B11,
A14,
C14,
D16
60
51
41
33
21
12
3
202
TxEN0
TxEN1
TxEN2
TxEN3
TxEN4
TxEN5
TxEN6
TxEN7
I, ID
Transmit Enable - Ports 0-7.
Active High input enables respective port transmitter.
This signal must be synchronous to the REFCLK.
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. The IP/ID resistors are disabled during H/W Power-Down mode. If a Pin is an output or an I/O, the IP/ID
resistors are also disabled when the output is enabled.
3. RxData[0:7]_0, RxData[0:7]_1, CRS_DV[0:7] and RxER[0:7] outputs are three-stated in Isolation and H/W
Power-Down modes and during H/W reset.