Moxtek, Inc. is a company based out of Orem, Utah, with a major focus on designing and building X-ray tubes that are primarily used in hand-held elemental analysis (x-ray spectroscopy). Moxtek sells power supply blocks packaged with their X-ray tubes to customers, providing a solution to the high operational voltages necessary for general X-ray use. X-ray tubes require very high voltages to operate. In handheld devices, the size of the components is very important. Therefore, Moxtek is seeking to improve on their existing high voltage power block by integrating it more completely with the X-ray tube and shrinking its size. This would reduce the size of the whole X-ray system and make the final customer product smaller, easier to handle, and lighter for repeated operator use. Moxtek has turned to BYU Capstone Team 24 to design and prototype a 50,000 V DC output voltage multiplier that can be integrated with Moxtek’s existing x-ray tube.

To statisfy Moxtek’s desire, Team 24 conceptualized two prototypes - parallel stack-up prototype and an inner/outer rings prototype. The parallel stack-up prototype successfully meets the customer requirements for a high-voltage multiplier. It multiplies voltage through ten stages of a Cockcroft-Walton schematic built using solid-state diodes and piezo-electric capacitor discs. The prototype functions with a loss of only three to four volts per stage. This is a negligible loss across ten stages when the input voltage is 2 kV. The inner/outer rings concept also multiplies voltage exceptionally well. It multiplies voltage through ten stages of a Cockcroft-Walton schematic built using solid state diodes sandwiched between inner and outer piezo-electric capacitor rings.