What this flyback switch is and where it fits
The Infineon ICE2QR1765XKLA1 is an integrated offline flyback switch from the CoolMOS™ CoolSET™-Q1 series, combining a 650 V avalanche-rated MOSFET with a PWM controller in a single 8-DIP through-hole package. It delivers up to 56.4 W in an isolated flyback topology, switching at a fixed 52 kHz. The part includes built-in fault protection — current limiting, overload, over-temperature, and over-voltage — reducing external BOM count for auxiliary power supplies in industrial and automotive-grade environments. The junction temperature range of -40°C to 150°C qualifies it for outdoor telecom, motor drive bias supplies, and under-hood converter stages.
56.4 W and 650 V — what they mean for your supply design
The 56.4 W continuous output rating sets the transformer core size and the secondary-side rectifier current. The 650 V breakdown MOSFET provides headroom for reflected voltage plus leakage inductance spike.
Through-hole package and mounting constraints
The PG-DIP-8 (0.300" body, 7.62 mm pitch) through-hole package suits wave-solder assembly and manual rework. The drain tab is internally connected to pin 8; ensure adequate copper area on the PCB for heatsinking if output power exceeds about 40 W in a 50°C ambient. The start-up voltage is 18 V, and the Vcc supply range is 10.5 V to 27 V — an auxiliary winding or bias regulator must stay within that window during all load conditions.