LAN89218AQ SMSC, LAN89218AQ Datasheet - Page 72

• Manufacturer Part Number: LAN89218AQ
• Description: Ethernet ICs High Perform Chip 10/100 NonPCI Cntrl
• Manufacturer: SMSC

Specifications of LAN89218AQ

• Ethernet Connection Type: 10BASE-T, 100BASE-TX
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Product: Ethernet Controllers
• Standard Supported: IEEE802.3, IEEE802.3u
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 3 V
• Maximum Operating Temperature: + 85 C
• Package / Case: TQFP-100
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Chapter 4 Internal Ethernet PHY
Revision 1.3 (02-23-10)
4.1
4.2
4.2.1
Functionally, the internal PHY can be divided into the following sections:
The data path of the 100Base-TX is shown in
4B/5B Encoding
The transmit data passes from the MII block to the 4B/5B encoder. This block encodes the data from
4-bit nibbles to 5-bit symbols (known as “code-groups”) according to
is mapped to 16 of the 32 possible code-groups. The remaining 16 code-groups are either used for
control information or are not valid.
The first 16 code-groups are referred to by the hexadecimal values of their corresponding data nibbles,
0 through F. The remaining code-groups are given letter designations with slashes on either side. For
example, an IDLE code-group is /I/, a transmit error code-group is /H/, etc.
The encoding process may be bypassed by clearing bit 6 of register 31. When the encoding is
bypassed the 5
Top Level Functional Description
100Base-TX Transmit
100Base-TX transmit and receive
10Base-T transmit and receive
Internal MII interface to the Ethernet Media Access Controller
Auto-negotiation to automatically determine the best speed and duplex possible
Management Control to read status registers and write control registers
MAC
Converter
NRZI
RJ45
th
MII 25 MHz by 4 bits
transmit data bit is equivalent to TX_ER.
TX_CLK
NRZI
Internal
MLT-3
Figure 4.1 100Base-TX Data Path
High Performance Single-Chip 10/100 Ethernet Controller for Automotive Applications
Converter
MLT-3
100M
PLL
CAT-5
DATASHEET
125 Mbps Serial
MII
MLT-3
MLT-3
72
Figure
by 4 bits
25 MHz
Driver
Tx
4.1. Each major block is explained below.
Encoder
4B/5B
MLT-3
Magnetics
by 5 bits
25 MHz
Table
4.1. Each 4-bit data-nibble
Scrambler
and PISO
SMSC LAN89218
Datasheet