BUY MC34063ADG https://www.utsource.net/itm/p/11249669.html

Description: The MC34063A is a monolithic control circuit containing the primary functions required for DC-to-DC converters. Features: - Internal 500V power MOSFET - Internal 0.5A current limit - Internal thermal shutdown - Internal frequency compensation - Output voltage adjustable up to 40V - Operating frequency up to 100kHz Applications: - Battery chargers - Switching regulators - DC-DC converters - Motor control - Lighting control - Low voltage power supplies (For reference only)