In the world of electronics, miniaturization is an ongoing battle. Twenty years ago, it’d take a device the size of car radiator to store one gigabyte of memory. Four times that (or more) can now be stored on a microSDHC card, which is probably smaller than your fingernail. Perhaps one of the most popular areas to shrink things down is on the a cell phone and that’s where Cypress Semiconductor has focused their energies, producing a USB transceiver that is only 2.2mm x 1.8mm.
As you can see from the provided picture, the MoBL-USB TX3LP18 transceiver is about the same size as the circular part of the “5” on the cell phone keypad. That’s pretty freaking small and they say that it delivers “ultra-low power consumption with a 0.5uA nominal sleep mode.” There’s no need for a dedicated 3.3V power supply. There’s also an integrated Phase-Locked Loop (PLL) “to supply USB clocking requirements without a dedicated crystal.” It’s all about being efficient, you see.
You want small? You got small.