
LXT9785 and LXT9785E Advanced 8-Port 10/100 Mbps PHY Transceivers
Datasheet
35
Document Number: 249241
Revision Number: 010
Revision Date: 30-May-2006
3.2
PQFP Signal Descriptions
3.2.1
Signal Name Conventions
Signal names may contain either a port designation or a serial designation, or a combination of the
two designations. Signal naming conventions are as follows:
Port Number Only. Individual signals that apply to a particular port are designated by the
Signal Mnemonic, immediately followed by the Port Designation. For example, Transmit
Enable signals would be identified as TxEN0, TxEN1, and TxEN2.
Serial Number Only. A set of signals which are not tied to any specific port are designated by
the Signal Mnemonic, followed by an underscore and a serial designation. For example, a set
of three Global Configuration signals would be identified as CFG_1, CFG_2, and CFG_3.
Port and Serial Number. In cases where each port is assigned a set of multiple signals, each
signal is designated in the following order: Signal Mnemonic, Port Designation, an
underscore, and the serial designation. For example, a set of three Port Configuration signals
would be identified as RxData0_0 and RxData0_1, RxData1_0 and RxData1_1, and
RxData2_0 and RxData2_1.
3.2.2
PQFP Signal Descriptions – RMII, SMII, and SS-SMII Configurations
descriptions. Ball designations are included for cross-reference.
Table 5.
RMII Signal Descriptions – PQFP (Sheet 1 of 3)
Pin-Ball
Designation
Symbol
Type1
Signal Description2,3
PQFP
PBGA
44
6
E6,
E12
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.
SeeCLK requirements.
61
62
E2,
F4
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.
52
53
C3,
D4
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
42
43
B5
A4
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.
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.