XRS10L220 Datasheet, PDF (1/38 Pages) Exar Corporation – SERIAL ATA II: PORT MULTIPLIER / PORT SELECTOR

EXSTOR - 1 XRS10L220
SERIAL ATA II: PORT MULTIPLIER / PORT SELECTOR
AUGUST 2008
REV. 1.02
FEATURES
GENERAL FEATURES
• Four independent 3/1.5Gbps SATA ports.
• Connects 2 host ports to 2 device ports.
• Supports 3/1.5Gbps rate detection/speed
negotiation.
• Supports power down modes - Active, partial,
slumber and power down.
• Advanced features configurable through MDIO
bus.
PORT MULTIPLIER/SELECTOR LOGIC FEATURES
• Low latency architecture.
• Supports OOB signaling for SATA applications.
Internal OOB detectors for COMRESET/
COMINIT and COMWAKE.
HIGH SPEED I/O FEATURES
• High speed outputs with programmable pre-
emphasis to drive long interconnects.
• Selectable high speed input equalization for
optimum reception.
• Compliant with SATA Gen-2i & Gen-2m
specification.
• Enables reliable data transmission over 1 meter
of FR-4 and 4 meters or more of unequalized
copper cable.
• Supports spread spectrum clocking (SSC) to
reduce EMI.
PHYSICAL FEATURES
• CMOS 0.13 Micron Technology
• Single 1.2 V Power Supply
• -40°C to 85°C Industrial Temperature Range
• No heatsink or airflow required
• 100-Pin LQFP Package
1.0 INTRODUCTION
The XRS10L220 provides the combined advantages
of the Serial ATA II Port Selector and Port Multiplier
implementations for Serial ATA II systems at 3.0
Gbps and 1.5 Gbps. Combining the capability to
address two Serial ATA devices from one external link
with support for a failover path from two independent
hosts, the XRS10L220 offers a leading solution for
propagation of high data rate Serial ATA products in a
wide variety of applications. The integration of Serial
ATA PHY links, a variety of digital logic capabilities,
rate adjust FIFOs, integrated low-cost clock oscillator
support, test and loopback features is achieved in a
low cost and lower power implementation.
The port selector function is used when dual hosts,
such as I/O controllers, must access single-port disk
drives in high availability storage subsystems where
redundancy and load sharing are important. The
outputs from the I/O controllers are multiplexed to a
Serial ATA drive through the port selector block of the
XRS10L220. Active/passive port selector in
XRS10L220 allows two different host ports to connect
to the same target in order to create a redundant path
to that target. In combination with RAID, the
XRS10L220 allows system providers to build fully
redundant solutions. This avoids the presence of a
single point of failure, and enables a fail-over path in
the case of host failure.
This port multiplier function is used when one active
host has to communicate with multiple SATA drives.
The XRS10L220 supports up to 2 SATA drives and
utilizes the full bandwidth of the host connection.
The XRS10L220 includes enhanced features such as
staggered HDD spin-up, power management control,
hot plug capability and support for legacy software.
The XRS10L220 acts as a retimer, maintaining
independent signaling domains between the drives,
hosts and the external interconnect.
The high-speed serial input feature: selectable
equalization adjustment and the high-speed serial
output feature: programmable pre-emphasis can be
used to compensate for ISI (Inter-Symbol
Interference) and increase maximum cable distances.
XRS10L220 meets tight jitter budgets in SATA
applications. Exar's serial I/O technology enables
reliable data transmission over 1 meter of FR-4 and 4
meters of unequalized copper cable.
Host and drive port speeds can be mixed and
matched, based upon inherent data rate negotiation
present in the SATA II specifications.
The MDIO bus allows simple configuration of the
XRS10L220 when needed. Receive equalization,
transmit amplitude and pre-emphasis and SSC
control are all configurable via the 2-wire MDIO
interface.
To summarize, the port multiplier functionality in the
XRS10L220 allows the system designer to increase
the number of serial ATA connections in an enclosure
that does not have a sufficient number of serial ATA
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • [phone] • FAX [phone] • www.exar.com