VT6420 Serial ATA/RAID Controller

VT6420The VIA VT6420 Controller delivers the benefits of Serial ATA and RAID in a cost effective and easily integrated single chip package, providing Serial ATA technology to platform providers and systems builders and enabling them to satisfy the requirements of multiple market segments.

Benefits of VIA Vectro VT6420

Multi-Functionality: Supporting Serial ATA and Parallel ATA interface, the VIA VT6420 is compatible with all kinds of ATA and ATAPI devices and provides up to four Serial ATA channels for extended connectivity, offering systems builders complete flexibility to incorporate HDD, CD-ROM, DVD and other types of ATA and ATAPI devices into PC systems.

High Serial ATA RAID Performance: The VIA VT6420 supports up to four Serial ATA channels, delivering data transfer rates of up to 150Mbps per channel, faster than any previous IDE interface. Supporting multi-level RAID maximizes performance and security of data, increasing read/write speeds, data integrity and fault tolerance. Low voltage signaling eliminates 5V tolerant I/O signals to ease hardware design and reduce cost and power.

Flexibility: The Serial ATA’s thin flexible cables of up to 1m is easier to route inside a PC, providing more flexibility in the PCB layout and opportunities for RAID systems with larger chassis and improves airflow within the chassis, enabling systems builders greater flexibility to design smaller and more compact PC systems. Reduced pin count connectors with a key assist blind mating, making it easier to install and reducing the risk of integration damage. The same interface and power connector is used for both 3.5 inch and 2.5 inch form factor products. This simplifies PC integration tooling and chassis design. It reduces part counts and therefore costs and enables interchange of form factors in the same chassis.


Compliant with the Serial ATA specification 1.0, the VIA VT6420 offers high performance Serial ATA RAID functionality to the full spectrum of PC processor platforms for desktops and servers. Supporting all kinds of ATA and ATAPI devices, including HDDs, CDs, DVDs, high capacity removable devices and featuring a 32-bit PCI interface, the VIA VT6420 enables seamless transition to the emerging Serial ATA technology.

The VIA VT6420 features two Serial ATA channels, supporting up to four devices and one Parallel ATA channel supporting up to two devices. The With dual channel Serial ATA, the VIA VT6420 delivers 12% more bandwidth than ATA-133 for data transfer between storage devices and CPU, bursting up to 150Mbps of data and offering a significant performance improvement in data intensive and bulk storage application. The VIA VT6420 furthermore incorporates a SATALite Interface, which paired with a single Silicon Image Sil3012 external PHY chip, adds two more Serial ATA channels at very low cost.

The VIA VT6420 provides multilevel RAID support including RAID level 0 for maximum performance, RAID Level 0 for maximum performance, RAID Level 1 for maximum security, RAID 0+1 and JBOD. To ensure backwards compatibility the VIA VT6420 also integrates a single channel parallel ATA-133 controller, eliminating the need for adaptors.

Featuring simple and practical cabling for improved airflow in the chassis, the VIA VT6420 enables OEMs and system builders to design smaller chassis, satisfying market demand for smaller and more compact PC systems. Smaller cable connectors with improved silicon design with a common location for both 3.5 inch and 2.5 inch drives save space and simplifies PC integration tooling and chassis design, while the lower voltage signaling of the VIA VT6420 alleviates the 5V tolerance support for Parallel ATA designs. Being compatible with a wide range of ATA and ATAPI devices, the VIA VT6420 equips OEMs and system builders with the flexibility to reach multiple market segments and price points.

The VIA VT6420 is the ideal solution for end-users to easily upgrade their storage devices and incorporates the emerging Serial ATA RAID standard into their systems, taking full advantage of the higher bandwidth, faster data transfer rates, improved data integrity and robustness of Serial ATA technology. Featuring a point-to-point host to device connection, installation is simple without the need for configuration as no jumper setting is required.

Backward compatibility with existing operating system drivers, the VIA VT6420 requires no update to software. The VIA VT6420 is compatible with a complete range of Intel, AMD and VIA based processing platforms, Microsoft® Windows® 9x/ME/NT4/2K/XP and major Linux based Operating Systems.

VT6420 Block Diagram


Key Features

RAID Controller
» Supports RAID Level 0, RAID Level 1, RAID Level 1 + 0 and JBOD

PCI Interface
» 33 MHz operation
» Supports PCI V2X mode
» Complies with PCI Local Bus Specification Revision 2.2

Ultra ATA-133 / IDE interface
» Single channel master mode hard disk controller supporting two enhanced IDE devices
» Supports ATA PIO mode 4, multi-word DMA mode 2 drivers and UltraDMA mode 6
» Extension to Ultra DMA-133 interface for up to 133Mbps transfer rate
» Supports Scatter/Gather Bus Master DMA mechanism for IDE drivers
» Supports Scatter/Gather host DMA mechanisms of Programming Interface for Bus Master IDE Controller Revision 1.0
» Supports PCI native and ATA compatible modes
» Complies with ATA/ATAPI-7

Serial ATA Interface
» Complies with Serial ATA Specification Revision 1.0
» Supports both internal and external PHY with Serial ATA speed of 150Mbps, each supports one SATA device
» Dual channel master mode PCI supporting up to four SATA devices. The SATA drive is capable of transfer rates up to 150Mbps

Other Features
» Supports external FLASH or EEPROM for BIOS expansion and RAID functions

Clock Input
» 33MHz for PCI Operation
» External crystal input for SATA port operation

Power Supply
» 3.3V for PCI and IDE operation
» 2.5V for Oscillator and Serial ATA port operation

» 0.22um, lower power CMOS process
» 15x15mm, 0.8mm ball pitch, 209 pin BGA

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