Memory card standard with PCIe 3.0 x1 interface, achieving 700–1,480 MB/s write speeds; primary format for Sony FX/Alpha cameras recording 4K 120p.
Technical Details
CFexpress Type A operates with a PCIe 3.0 x1 connection and achieves practical write speeds between 700-1,480 MB/s depending on the manufacturer. The cards use 3D NAND flash memory with SLC or MLC architecture and offer an operating temperature range of -25°C to +85°C. Power consumption is a maximum of 2.5 watts, significantly lower than Type B cards. The electrical contacts are based on a modified SD card format with additional PCIe lanes.
History & Development
The CompactFlash Association introduced CFexpress Type A in 2017, with the first commercial implementation by Sony in 2019 with the CEA-G series. Sony first integrated the standard in 2020 into the Alpha 7S III and FX3 to enable 4K-120p recording. In 2021, other manufacturers like ProGrade Digital and Lexar followed. The development responded to the increasing data demands of 4K-60p video and future 8K formats.
Practical Application in Film
CFexpress Type A is primarily used in Sony cameras of the FX series and Alpha line, where it enables continuous 4K-120p recording in XAVC S-I. In documentaries like "Free Solo" (2018), comparable technologies allowed for uninterrupted long-term recordings. The high write speeds eliminate buffer overflows for RAW video and high-speed photography. Disadvantages include the high cost of 400-800 Euros per card and limited manufacturer support outside of Sony.
Comparison & Alternatives
CFexpress Type A differs from Type B in its smaller form factor (vs. 38.5×29.8 mm) and lower speed, but is significantly faster than SD UHS-II (300 MB/s). XQD cards offer similar performance but use a different form factor. Canon relies on CFexpress Type B in its Cinema EOS series, while Panasonic sticks with SD UHS-II. Type A is suitable for compact cameras with high data requirements, while Type B is for flagship models with maximum performance demands.