Storage
Solutions
Serial ATA II
88SM4140
1:4 Port Multiplier Solution
PRODUCT OVERVIEW
The Marvell
88SM4140 port multiplier device offers the industrys first solution for port expansion. The device
enables one active host connection to communicate with up to 4 Serial ATA disk drives. The device uses Marvells
production-proven Serial ATA PHY technology and supports both 1.5 Gbps and 3.0 Gbps speeds with adjustable
pre-emphasis and amplitude settings on all 5 ports (1 host, 4 device) for tuning high-speed, long-trace backplane
implementations. The device also provides one Storage Enclosure Management Bridge (SEMB) port for communication
with a Storage Enclosure Processor (SEP). Per the Serial ATA II specification, the 88SM4140 device supports
command-based and FIS-based switching supporting simultaneous queued operations to all attached devices.
The 88SM4140 product also supports a Marvell-proprietary mode called queued command based switching which
enables the performance advantages of FIS-based switching but with reduced complexity.
FEATURES
BENEFITS
1.5/3.0 Gbps PHY operation
Supports next-generation HDD designs
FIS-based switching
Superior performance by allowing the host to have outstanding
commands to multiple devices at any point in time
Queued command-based switching (Marvell Proprietary)
Allows performance advantages of FIS-based switching but with
reduced complexity
1 SEMB port
Allows connection to off-chip SEP for enclosure
Staggered HDD spin-up
Allows host-side control of HDD spin-up to manage power budget
during system power-up
SATA BIST over host and device links
Enable optimal per-port PHY tuning for Serial ATA backplane designs
Programmable pre-emphasis and amplitude per port
Reduces EMI for enterprise storage and server applications
Spread Spectrum Clocking (SSC)
Reduces EMI for enterprise storage and server applications
1.2V and 3.3V power
Interface flexibility
Compatible with Marvell 88SX60xx Serial ATA II host controllers
End-to-end system interoperability
and 88SA8040 Parallel ATA to Serial ATA bridges
Fig 1. Serial ATA II Port Multiplier (88SM4140) Block Diagram
Port 3 PHY
Port 0 PHY
Serial
ATA
Host
Serial
ATA
Device
0
REFCLK
UART/SEMB
Serial
ATA
Device
1
Serial
ATA
Device
2
Serial
ATA
Device
3
PLL
UART
Control
SEMB
Control
Port Arbiter
MUX
FIFO
Port 1 PHY
Port 2 PHY
Host PHY
PM_CTRL
Serial ATA II 1:4 Port Multiplier Solution
Marvell Semiconductor, Inc.
700 First Avenue
Sunnyvale, CA 94089
Phone 408.222.2500
www.marvell.com
APPLICATIONS
The 88SM4140 1:4 Serial ATA II port multiplier, when combined with the Companys market-leading 88SX60xx Serial ATA II
4 or 8-port host controllers, will enable enterprise-class port expansion inside storage arrays, RAID subsystems and servers.
Further, the port multiplier is also ideal for next-generation home storage applications, enabling up to 1 Terabyte (1,000 GB)
of storage expansion for video, audio and high-resolution graphics or photos inside digital set top boxes, digital video recorders
(DVRs), or PCs and laptops. For example, 1 Terabyte of expanded storage could hold over 250,000 songs or over 1,000 full-
length feature films.
THE MARVELL ADVANTAGE:
The Marvell 88SM4140 Serial ATA II port multiplier comes with a complete set of hardware and software
development tools to assist engineers developing next generation storage networking solutions. Marvells worldwide field applications
engineers collaborate closely with storage networking equipment vendors to develop and deliver innovative products to market. Marvell
utilizes recognized world-leading semiconductor foundry and packaging services to reliably deliver high-volume and low cost total
solutions.
For more information, visit our website at www.marvell.com.
Fig 2. Serial ATA Port Multiplier (88SM4140) Applications Diagram
Processor
Server
External
Serial ATA
JBOD
North Bridge
Memory
Serial ATA
Host Controller
(88SX6081)
I/O Hub
64-Bit PCI-X
Serial ATA II
1:4
Port Multiplier
(88SM4140)
2
Copyright 2004. Marvell International Ltd. All rights reserved. Marvell, the Marvell logo,
Moving Forward Faster, Alaska, Fastwriter, GalNet, PHYAdvantage, and Prestera are registered
trademarks of Marvell. Discovery, DSP Switcher, GalTis, Horizon, Libertas, Link Street, NetGX,
RADLAN, Raising The Technology Bar, The Technology Within, UniMAC, Virtual Cable Tester, and
Yukon are trademarks of Marvell. All other trademarks are the property of their respective owners.
88SM4140-001
02/04
PDF 
ZIP