This part is a kind of semiconductor called 8339.

Function of this product has 15KV ESD PROTECTED/ LOW POWER RS-485/RS-422 TRANSCEIVER.

Manufacturers : STMicroelectronics

Image and pinout :

Some of the text within the PDF file :

ST485E ±15KV ESD PROTECTED, LOW POWER RS-485/RS-422 TRANSCEIVER s s s s s s s s s s LOW QUIESCENT CURRENT: 300µA DESIGNED FOR RS-485 INTERFACE APPLICATIONS -7V TO 12V COMMON MODE INPUT VOLTAGE RANGE DRIVER MAINTAINS HIGH IMPEDANCE IN 3-STATE OR WITH THE POWER OFF 70mV TYPICAL INPUT HYSTERESIS 30ns PROPAGATION DELAYS, 5ns SKEW OPERATE FROM A SINGLE 5V SUPPLY CURRENT LIMITING AND THERMAL SHUTDOWN FOR DRIVER OVERLOAD PROTECTION ESD PROTECTION: ±15KV (H.B.M.) ±8KV (IEC-1000-4-2 CONTACT DISCHARGE) ALLOWS UP TO 64 TRANSCEIVERS ON THE BUS DIP SOP DESCRIPTION The ST485E is al low power transceiver for RS-485 and RS-422 communication. Each driver output and receiver input is protected against ±15KV electrostatic discharge (H.B.M.) (ESD) shocks, without latcup. These parts contain one [ ... ]

8339 PDF Datasheet Download