Murata Power Solutions Surface Mount Pulse Transformer 1:2.14 Turns Ratio, 142μH Prim. Inductance, 0.5Ω Prim. Resistance

Isolation converter transformer with isolation voltage of 1.5 kVrms (C/MC types) and 4 kVrms (VC/VMC types)
Specifically designed to provide isolated RS-485 and RS-232 interface
Industry standard pinout, low profile, through hole and SMT
3.3V and 5V versions with frequency range upto 500 kHz