The BV101 is a USB to serial converter that utilises the FTDI IC. In addition to this it also has an on board 5V regulator capable of supplying up to 100mA. This effectively isolates the PC's USB power supply to give protection from short circuits.

There is a variant of this called the BV103 that has two on board regulators, one at +5V and the other at 3.3V


From July 2014 the BV101 is no longer available