Ultravolt 25A12-N4-25PPM-F-M-E Non-Isolated DC-DC Converters A-Series DC to HVDC Converter, Single output (Unipolar), +12V Input, -25kV DC HVout, 4W, Thru-hole mount, Regulated, Standard Interface, 25ppm/ C Temperature Coefficient, Ripple reduction filter, Eared mounting flange