INTRODUCTION
   The following Application Note describes an off–line switching power supply utilizing a precision programmable reference to regulate a 1.8 volt output. The center of the app note is the MC33363B, a monolithic SMPS controller with a 700 volt power switch, and the NCP100, a sub–one volt precision programmable reference. The system design and analysis will be described in detail.
   The design requirements are for a universal off–line converter with a 1.8 volt, 1.0 ampere single output with less than 50 millivolts ripple and operates at 100 kHz. Most of the components selected are surface mount. This design is separated into the generic circuit of the off–line converter and the feedback network.