The TB271 series of RS232 fiber optic line drivers provides maximum protection from ground currents and noise interference between equipment as well as increases operating distances up to 2km. Three versions are available, supporting RS232 serial interfaces. The TB271 series achieves power from the transmit data line, whereas, the TB271A series has an external power supply (included). DB25M and DB25F versions available. Fiber optic connection utilizes dual ST connectors and duplex 62.5/125 multimode cabling.