FT232B - USB to Serial UART, FTDI Chip FTDI Chip recommends using the FT323R (RS 406-580) in new designs.

The FTDI Chip FT232B is a USB to serial UART interface and an ideal solution to add USB to older designs. Royalty-free drivers for the most common operating systems are available from FTDI website. http://www.ftdichip.com - TTL data rate 300 Baud to 3 MBaud
- RS232 data rate 300 Baud to 3 MBaud
- RS422/RS485 data rate 300 Baud to 3 MBaud
- 384 Byte Receive buffer/128 Byte Transmit buffer for high data throughput
- Full hardware assisted or X-On/X-Off handshaking
- Support for event characters and line break condition
- Auto transmit buffer control for RS485
- Compact 32-pin (7 x 7 mm) LQFP package
- Integrated 6 MHz - 48 MHz clock multiplier
- Integrated 3.3 V regulator - no external regulator required
- 4.4 V to 5.25 V single supply operation
- UHCI/OHCI compliant