USB-to-SDIO host IC expands microSD-compatibility

September 17, 2015 // By Julien Happich
Designed by Elan Digital Systems, the VUB300 is a unique IC that converts a USB interface into an SDIO Host Interface, suited to SD or microSD cards.

The VUB300 is a single-chip USB-to-SDIO hardware bridge that allows SDIO- and SD-compliant devices to be connected to any host PC via its USB port. The VUB300 is the ideal solution when a target system has no spare SDIO ports but does have available USB ports.

The capability and intelligence to handle both the USB and SDIO protocols is all in hardware, allowing the IC to seamlessly translate data between the two formats. A unique and important user benefit of VUB300 is its universal support for any SDIO device, allowing it to run with any manufacturer's existing driver and application software without the need for any modification - drivers integrate into the standard operating system SD/SDIO driver stack.

The SDIO Host function conforms to the SDIO Host specification with a generic USB "wrapped" interface to extend SDIO host controller support to the USB bus. Key features of the device include low power, small package size and high data throughput. With a USB2.0 Hi-Speed connection, transfer rates of up to 480 Mbps are possible, but the VUB300 is also backward-compatible with Full-Speed USB2.0 and USB1.1 ports.

The VUB300's SDIO interface supports 1bit or 4bit SDIO and SD Interrupt with automatic card detection. It is also suitable for bus-powered applications, requiring under 450mW from a 3.3V supply. The chip comes in a 36-pin 6x6mm QFN device rated for -40 to +85ºC operation.

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