Adafruit's Latest 512MB SPI Flash Part Is SD Card Technology on an SPI Breakout Board

Adafruit has announced the launch of a new breakout board packing 512MB of SPI-connected flash memory, but with a difference: It's a fully-functional SD card, compatible with any libraries designed for standard-format SD card storage.

"The breakout will act just like a 512MB sized card with FAT formatting (it’s pre-formatted)," the company explains of its latest release. "You might be wondering why you’d want such a thing — after all, you can’t plug it into a computer to get the files off like microSD cards. For some use cases, such as data logging in a high-vibration device where you don’t want the SD card to come loose, or for when you need to reduce size, or when the microcontroller provides a USB mass storage interface, this chip could very useful."

The compact breakout is based on a NAND memory chip and includes a controller which handles wear-leveling and error correcting code (ECC) internally, with no need to add such code to your project — nor to manually erase blocks before writing new data, as you would with a traditional SPI flash part. An included level shifter allows the part to work on 3.3V or 5V logic, while there's a 3.3V regulator and a pull-up resistor on the chip select pin.

According to the spec sheet, the part can be clocked up to 50MHz and is equivalent to an SD card Speed Class 8 for writes — however, Adafruit warns, you're unlikely to get maximum performance through a one-bit SPI interface when compared with a fully-wired SDIO interface.

The part is now available on Adafruit for $9.50 before volume discounts, and requires no additional code beyond existing libraries for communicating with standard SD card storage devices.