A new technology developed by Micrel makes it possible for manufacturers to bridge the major stumbling block that has kept them from bringing USB to PDAs. The new technology converts the signal voltage used in the ASICs found in PDAs and other portable devices to the voltage used by USB. According to Micrel:
The MIC2550 is fully compliant to USB Specification Rev 1.1 and converts signaling voltages as low as 2.5V to the USB standard of 3.3V. This solves the problem of interfacing USB with today's low-voltage, deep submicron ASICs used in cellular phones, PDAs and other mobile devices.
The MIC2550 is designed to connect directly to the USB voltage and data bus at speeds up to 12Mbs. To support USB suspend current requirements, it consumes less than 200uA operating current. For very low current consumption, a suspend control pin is provided that shuts down the internal amplifier.
This device is aimed at manufacturers, not consumers, and will probably be making its way to consumer products during the next 8-12 months.
The Mac Observer Spin: Once again, there are several layers to this story. The one most important to Mac users is the fact that USB connectivity for cell-phones, PDAs, and here-to-for unannounced portable devices will make it far easier for manufacturers to make these items Mac compatible! This is good! Currently, handheld computers and PDAs use either infrared or serial connectivity to interface with computers. Serial connectivity is implemented differently with Macs and PCs which means that cross-platform devices have to have redundant hardware or different versions. USB will eliminate those needs.
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