BUY TEXAS INSTRUMENTS/TI UC3846N https://www.utsource.net/itm/p/8502343.html

The UC3846N is a high performance current mode PWM controller manufactured by Texas Instruments. It is a 16-pin DIP package and is designed for use in off-line and DC-to-DC converter applications. Features: * Internal Slope Compensation * Internal Soft-Start * Internal Leading Edge Blanking * Internal Oscillator * Internal Voltage Reference * Cycle-by-Cycle Current Limiting * Under Voltage Lockout * Programmable Frequency Applications: * Switching Power Supplies * Uninterruptible Power Supplies * Motor Control * Battery Chargers * DC-DC Converters (For reference only)