File System


Integrating FAT File System into a product requires a lot of system resources. It also requires intensive development efforts, from the file system libraries to the USB Host and SD card drivers. We have a long history designing FAT file system hardware.

File System

With our OEM file system modules and chipsets any system can quickly access files on SD and USB storage devices minimal resources -- from off the shelf OEM modules for quick integration to chipsets available to implement right into your own system. Simple commands over UART (serial), SPI, or I2C are used to interact with the file system at speeds reaching up to 4,000,000 bytes per second. These products are capable of accessing two USB storage devices and one memory card simultaneously, support long file names (LFN), and are licensed for commercial use.

Long File Name Support

ALFAT and Long File Names

The original FAT file system only supported filesnames up to eight characters in length (8.3 format). Our file system solution supports modern Long File Names (LFN) on FAT file systems enabling the use of complete filenames.

USB 2.0 Speeds

ALFAT gives you the option to add a USB 2.0 PHY on one of the USB interfaces. The ALFAT OEM board includes the PHY which can be used as-is or as a starting in your own design since we make its schematic available.


SD Reader Mode and the SDR Board

In the SD Reader mode (SDR) the file system chipset still accepts commands to access files on the SD card but it also makes itself appear as an SD card reader through USB, making this an ideal solution for data logging applications.


A Proud History

Dev Board

When introduced in 2003, ALFAT was GHI Electronics’ first and original file system chipset. It supported file system on both SD/MMC and CompactFlash. In 2005, USBwiz was introduced to add support for USB mass storage devices (MSC). The low-cost uALFAT being introduced in 2007. The entire product line was completely reinvented in 2012 with the introduction of the F40 (ALFAT) chipset. The ultra low-cost F20 is the newest offer, announced in 2016. With over ten years of history we're still proud to have one of the most advanced chipsets on the market.

Software Options

Our file system products are programmed by the host so there are a variety of options available depending on your product.


Developer resources can be found on our documentation website.

Place Order

Description Part Number MSRP Availability
ALFAT (F40) SoC ALF2X-SC-512 $15 @ 100 Active
F20 SoC F20SC-SC-558 $6 @ 100 Active
ALFAT OEM Board ALFAT-OM-337 $35 Active
ALFAT SD Board ALFAT-SD-338 $30 Active
ALFAT USB Board ALFAT-USB-428 $30 Active
ALFAT SDR Board AFSDR-FS-523 $35 Active
F20-uSD F20FS-546 $14 Active
uALFAT SoC UALFAT-1 $20 Legacy
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