Control circuitry handles inrush current, and may provide under voltage and/or over voltage monitoring and handling, as well as remote enable handling. The circuitry may advantageously employ a sense capacitor in parallel with an input capacitor (e.g., bulk input filter capacitor), and a current mirror to produce a signal proportional to input current. A clamp circuit may control a series pass device to regulate current in response to the proportional signal, or to interrupt current flow in response to an under voltage or over voltage condition or receipt of a signal indicative of a disable state. An enable signal may be summed into a comparator that handles under voltage condition determination.