A low voltage to high voltage level shifter circuit for MEMS application

High voltage (>15 V) drivers are integrated into the VLSI chip for MEMS application with the development of SOC technology. The pre-driver circuit, which generates the pull-up and pull-down signal, is mainly a voltage level shifter circuit. It converts the low voltage control signal to high voltage control signal. Conventional voltage level shifter circuit using high voltage NMOS and high voltage PMOS operates well on 0.8 μm process. However, with the continuous process shrinking, conventional voltage level shifter circuit is not suitable for high voltage power supply due to the reduced breakdown voltage of the high voltage devices. Although stacked high voltage devices can be applied to solve this issue, the circuit will have DC leakage current and the internal high voltage swing problem. This paper describes a new low voltage to high voltage converter circuit. By using all the low voltage devices, the DC leakage current and the high voltage swing node have been eliminated. This circuit is fabricated in 0.35 SOI process. Both simulation and test results validate its operations for controlling high voltage drivers.