The Supertex HV9906DB2 demo board contains all circuitry necessary to demonstrate the features of the HV9906 second order power supply controller. The power converter of the demo board consists of an input buck-boost stage and an output buck stage. The output voltage polarity is negative. Due to its unique quadratic input-to-output DC voltage transfer ratio, the converter can operate directly off AC line to produce low-voltage output without need for electrolytic capacitors. HV9906 is designed for optimal controlling this type of power converter or other types of two-stage multi-converters.