App note: High voltage, low noise, DC/DC converters

An app note from Linear Technology: High voltage, low noise, DC/DC converters (PDF!) Photomultipliers (PMT), avalanche photodiodes (APD), ultrasonic transducers, capacitance microphones, radiation detectors and similar devices require high voltage, low current bias.  Additionally, the high voltage must be pristinely free of noise; well under a millivolt is a common requirement with a few hundred microvolts sometimes necessary. […]