A High Performance 4500 Volt Electron Multiplier Bias Supply for Satellite Use

A tuned-secondary sinewave oscillator combined with a Cockcroft-Walton voltage multiplier has been developed which produces 40 μA at 4500 volts from 12 VDC with 80% efficiency. Optimum efficiency is obtained by considering the Cockcroft-Walton multiplier as part of the oscillator design. Equations are developed for calculating the multiplier output voltage and ripple as a function of the oscillator output frequency and amplitude, the capacitance of the multiplier, the number of multiplier stages, and the load current. The Atmosphere Explorer Photoelectron Spectrometer electron multiplier bias supply is also described to illustrate practical design tradeoffs and techniques employed when the supply is used in a satellite-borne particle detection experiment.