The CompactFlash Association has announced the availability of its new CF5.0 specification, offering greater capacities and speeds. Enabling 48-bit support (as against the current 28-bit), the new specification theoretically allows for an increase in the maximum capacity to 144 petabytes (1PB = 1000 terabytes), up from the current limitation of 137GB and also increases data transfer unit size from 128KB to 32MB. Although it is primarily aimed at the camcorder market, we expect to see compatibility added to future HD-enabled DSLRs.

Press Release:


CF5.0 Adds New Features for Predictable Performance & Market Expansion

CUPERTINO, Calif.--The CompactFlash Association (CFA) announces availability of the recently approved CF5.0 Specification.

The CF5.0 work group was formed in November, 2008 to add key features to the already popular CF4.1 specification based on the PATA (Parallel ATA) interface. The new CF5.0 specification adds the following key features/benefits to the memory card that started the digital photography revolution.

Key Feature


48 bit Addressing (Mandatory)

Capacity points beyond current limitation of 137GB (up to 144PB) & more efficient data transfer (32MB per transfer versus 128K per transfer)

Data Set Management Command/Trim (Mandatory) More efficient cleanup of unused space on memory card (LBA’s)
Update ATA References to ATA-6 & ATA-8/ACS-2 Access to advancements in the ATA standard
Performance Control (optional)

Card performance quality of service framework

Video Performance Guarantee (Optional) Quality of service for video capture applications to ensure quality recordings with no dropped frames
Identify Device CFA Specification Version Number (Mandatory) Easier for host to determine card capabilities
Changed Interface Electrical Specification to Better Comply with the ATA Standard (Mandatory) Easier and better card design, compatible with advanced hosts.

Mr. Shigeto Kanda of Canon and the CFA chairman of the board said, “The higher capacity and higher performance of CF cards enabled by the 48-bit addressing feature in the CF5.0 specification will further increase the value of DSLR cameras. The Video Performance Guarantee feature of the CF5.0 specification will help CF cards to expand into new markets such as high-speed movie equipment like professional video camcorders.”

To help manufacturers and consumers differentiate the new CF5 cards, the CompactFlash Association has created an evolutionary CF5 compatibility mark. Additionally, since the Video Performance Guarantee feature is optional, the CompactFlash Association has created a Video Performance Guarantee compatibility mark that host and card manufacturers can use to help end users choose the right card.

CompactFlash card slots are commonly used in digital cameras, video cameras and other electronic platforms including embedded systems, single board computers, data recorders, heart monitors, defibrillators, and slot machines.

CFA members can participate in the CFA working groups and access documentation as the specifications are completed. Companies interested in participating in the definition of new CFA standards are encouraged to join the CompactFlash Association and to participate in work groups.

Additional information about CF5.0 including a whitepaper on Performance Control features and the latest CompactFlash published Specification; Revision 5.0 is available to download from the CFA web site at