USB-232-OPTO
  
              Price: 
                
          42        
                    
            
          
      
  USB-232-OPTO is an optoisolated USB to RS232 converter based on PL2303HX. Thanks to its on-board DC-DC converter it doesn't require any additional power supply, but is completely USB bus-powered. Its small form factor and low price make it ideal for an engineer's laptop as well as for industrial computers where interface isolation is a must. It supports baud rates of up to 128kbps and features the following signals: TXD, RXD, RTS, CTS.
Drivers for most operating systems are available at  Prolific web site .