Multilayer Rosen-type piezoelectric transformer prepared with Pb(Mg1/3Nb2/3)O₃–PbTiO₃ single crystal

A multilayer Rosen-type piezoelectric transformer with the size of 20 mm length, 4 mm width and 2.8 mm thickness has been fabricated using ferroelectric single crystal Pb(Mg 1/3 Nb 2/3 )O 3 –PbTiO 3 . The electrical properties of the prepared transformer were systematically investigated. Results show that the efficiency of this transformer can reach 92% and the voltage step-up ratio under open circuit exceeds 100. Comparing this with the single-layer Rosen-type transformer, we reported lower output impedance and larger step-up voltage ratios have been obtained under the same load resistance. Near the resonance frequency, this transformer has a much purer vibration mode and wider working bandwidth. Furthermore, this transformer can successfully drive a 0.5 W LCD backlight under a lower input voltage without obvious temperature rise. These global properties make this piezoelectric transformer a promising candidate for small power inverters and cryogenic applications.