Wurth Electronics offline flyback transformers are available for both fixed-frequency and quasi-resonant operation mode and have multiple output parts available. The MID-OLSTM series features nominal input voltages from 85 V_AC to 265 V_AC (120 V_DC to 375 V_DC) and isolation voltages from 2 kV_AC up to 5 kV_AC. The MID-OSLTM series is designed for several ICs from STMicroelectronics.