ADVANCE DATA SHEET
BCM5238
10/100BASE-TX Octal-Φ™ Transceiver
GENERAL DESCRIPTION
FEATURES
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10BASE-T/100BASE-TX IEEE 802.3u compliant
The BCM5238 is an octal 10/100BASE-TX transceiver
for Fast Ethernet switches. The device contains eight full-
duplex 10BASE-T/100BASE-TX Fast Ethernet
transceivers, each of which performs all of the physical
layer interface functions for 10BASE-T Ethernet on
Category 3, 4 or 5 unshielded twisted-pair (UTP) cable
and 100BASE-TX Fast Ethernet on Category 5 UTP
cable. Pseudo-100BASE-FX mode is supported through
external fiber-optic tranceivers.
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Single-chip octal physical interface—SMII to
magnetics
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Option—Source Synchronous SMII (SSSMII)
Fully integrated digital adaptive equalizers
125-MHz clock generator and timing recovery
On-chip multimode transmit waveshaping
Edge-rate control eliminates external filters
HP auto-MDIX
Cable length Indication
Cable noise level Indication
The BCM5238 is a highly integrated solution using 0.18-
micron technology, combining digital adaptive
equalizers, ADCs, phase locked loops, line drivers,
encoders, decoders and all the required support circuitry
into a single monolithic CMOS chip. The BCM5238
complies with the IEEE 802.3 specification, including the
auto-negotiation subsections.
IEEE 802.3u-compliant auto-negotiation
Shared MII management interface up to 25 Mbps
Programmable serial LED pins
Programmable parallel LED pins
Interrupt output capability
Loopback mode for diagnostics
IEEE 1149.1 (JTAG) and NAND-chain ICT support
Low-power dual-supply 2.5V/1.8V CMOS technology
Compatible with 3.3 V I/O
The BCM5238 design results in robust performance over
a broad range of operating scenarios. Problems inherent
to mixed-signal implementations, such as analog offset
and on-chip noise, are eliminated by employing field-
proven digital adaptive equalization and digital clock
recovery techniques.
128 MQFP and 256-pin FBGA package
APPLICATIONS
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Fast Ethernet switches
Multimode
Xmt DAC
TD± ±{1:8}
TXD{1:8}
10BASE-T
PCS
8
8
SSYNC
SSSMII_TXC
Auto
MDIX
Baseline
Wander
Correction
100BASE-X
PCS
SSSMII_RSYNC
SSSMII_RXC
RXD{1:8}
Digital
Adaptive
Equalizer
RD± ±{1:8}
ADC
Auto-Negotiation
/Link Integrity
CRS/Link
Detection
INTR/SLED_DO
LED1{1:8}
LED/INT
Drivers
8
8
LED2{1:8}
REF_CLK
Clock
Recovery
Clock
Generator
SSSMII_DIS/SLED_CLK
MODES/CONTROLS
Bias
Generator
13
RDAC
MII
Mgmt
Control
MDC
MII
Registers
JTAG
Test Logic
MDIO
JTAG
5
Figure 1: Functional Block Diagram
5238-DS03-405-R
16215 Alton Parkway • P.O. Box 57013 • Irvine, California 92619-7013 • Phone: 949-450-8700 • Fax: 949-450-8710
1/31/03