On-chip Digitally Tunable High Voltage Generator for Electrostatic Control of Micromechanical Devices

Micromechanical structures with capacitive readout provide a feasible alternative for feedback by utilizing electrostatic forces without any requirement for additional electrodes. For this purpose high voltages are often required. This paper presents circuit structures for on-chip high voltage generation. A high voltage amplifier with digitally controllable output or a high voltage DAC is implemented and, as an example application, the DAC is used for quadrature compensation of a microelectro-mechanical gyroscope. The implemented high voltage generator achieves output voltages between zero and 27 V in 29 mV steps. The charge pump output voltage is limited in all cases to prevent reliability problems