The present invention provides an improved form of inverter circuit which refines the known conventional circuit to reduce its offset and then uses a combination of this refined circuit and a feedback type power converter to achieve low output offset, very high speed and very high current efficiency. According to a first aspect of the present invention there is provided a voltage converter circuit comprising serially coupled first and second gain stages and switching means arranged between the second gain stage and an output for the converter circuit, the first gain stage having a gain greater than that of the second gain stage, and the second gain stage having a bandwidth greater than that of the first gain stage. According to a second aspect of the present invention there is provided A method of voltage conversion comprising serially coupling first and second gain stages and providing switching means arranged between the second gain stage and an output terminal, selecting the first gain stage to have a gain greater than the second gain stage, and selecting the second gain stage to have a bandwidth greater than that of the first gain stage.