The UC1524A family of regulating PWM ICs has been designed to retain the same highly versatile architecture of the industry standard UC1524 (SG1524) while offering substantial improvements to many of its limitations. The UC1524A is pin compatible with ''non-A'' models and most existing applications can be directly interchanged with no effect on power supply performance- Using the UC1524A, however, frees the designer from many concerns which typically had requered additional circuitry to solve.