CFast vs. SD Card
Comparing 2 standards across 12 specifications. 12 key differences identified.
CFast is a high-speed solid-state memory card standard developed by the CompactFlash Association (CFA) based on the Serial ATA (SATA) bus. Introduced with CFast 1.0 (SATA-II 3 Gbps) and refined in CFast 2.0 (SATA-III 6 Gbps), it delivers data throughput up to 550–600 MB/s in a rugged 24-pin form factor, widely adopted in professional cinema cameras (ARRI, Blackmagic, Canon).
The SD Card (Secure Digital) is the global standard removable flash memory form factor established in 1999 by Panasonic, SanDisk, and Toshiba (SD Association). Measuring 32.0 × 24.0 × 2.1 mm, it spans capacity generations from original SDSC (up to 2GB) and SDHC (up to 32GB) to SDXC (up to 2TB) and SDUC (up to 128TB).
Specification Comparison Table
12 Parameters| Parameter / Spec | ||
|---|---|---|
|
Governing Body
|
CompactFlash Association (CFA) | SD Association (SDA) |
|
Physical Dimensions
|
36.4 mm × 42.8 mm × 3.6 mm | 32.0 mm × 24.0 mm × 2.1 mm |
|
Bus Interface / Protocol
|
Serial ATA (SATA 3.0 / 6 Gbps in CFast 2.0) | — |
|
Physical Connector Form Factor
|
24-pin keyed interface (7-pin SATA signal + 17-pin SATA power & control) | — |
|
Peak Data Throughput
|
Up to 550–600 MB/s (SATA-III physical ceiling) | — |
|
Nominal Operating Voltage
|
3.3V nominal | — |
|
Video Performance Guarantee
|
VPG-130 (130 MB/s minimum sustained write for 4K ProRes/RAW) | — |
|
Pin Configurations
|
— | 9 pins (UHS-I / Legacy) / 17 pins (UHS-II / UHS-III dual-row) / 19 pins (SD Express) |
|
Capacity Standards
|
— | SDSC (≤2GB), SDHC (4–32GB), SDXC (64GB–2TB), SDUC (2TB–128TB) |
|
Standard File Systems
|
— | FAT12/16 (SDSC), FAT32 (SDHC), exFAT (SDXC / SDUC) |
|
Operating Voltages
|
— | 2.7V–3.6V (Standard) / 1.8V (UHS-I/II signal voltage) |
|
Mechanical Features
|
— | Write-Protect slide notch (left edge), 45-degree polarized corner keying |