High-Voltage Regulator Has Built-In Protection

The VB408 is a fully protected, adjustable positive voltage regulator that can be connected to a 400 vdc source or used in off-line applications where it's directly connected to a rectified ac-mains supply. The device, which is fabricated on the firm's High Voltage VIPower process, offers an output that's continuously adjustable by means of a resistive divider to any value between 1.25V and the input voltage minus a 30V dropout. Typical output current is 40 mA, which is internally limited. The part also offers built-in short circuit and thermal shutdown protective circuits with fast protection against high-voltage transients. Line regulation is 100 µV/V and load regulation is 6 mV/V.