Satechi Has Produced Some Innovative Accessories in the past and one of great interest to me is the uCharger Hi-Speed ESB Charging Adapter which uses software to tell your computer to up the amperage of the USB port in order to facilitate more rapid charging. This small USB dongle plugs into your computer and allows you to press a button to toggle between modes. Blue is for all of USB charging except the Galaxy Tab and Red is for all kinds of USB charging except the iPad.
USB 2.0 specifies a unit load of 100 mA with a maximum of 5 unit loads per device or 500 mA. USB 3.0 ups this amount to 150 mA with a total of 6 per device or 900 mA. Satechi specifies the output of its uCharger varies from 700 mA-2,100 mA and it can charge a device up to four times faster. The simple math here is if you were to multiply the maximum amperage of the USB 2.0 connection of 500 mA times four, you would get 2,000 or just under the maximum amount of output from the device.
The trick here is software where the dongle tells the computer it needs more current. It is worth mentioning that if your computer has a bunch of USB accessories hanging off of it or just one which is drawing a large amount of current, the computer may deny the request to up the amperage as the bus simply can’t supply any more. In other words, like IP communications over the internet, users get best-effort delivery on their request.
Still, at $9.99 it is worth a shot – even if it speeds up your charging some of the time. I’ll ask the company to send me one for testing. If it works as the company claims, it will allow a user to charge an iPad 2 in 5 hours and twenty minutes, which is pretty impressive considering you don’t need a separate charger.