Universal Resonator Control ASIC for Low C- SWaP INS

Abstract

A novel Universal Resonator Controller (URC) architecture and ASIC design is presented for precision, wideband resonator velocity control and the digitally demodulated readout of resonator velocity and frequency with the designed resolution «100ppb/rt-Hz), linearity (lppm) and sensor bandwidth (>100Hz) required for navigation grade vibratory inertial sensors. In this paper, our two-channel URC ASIC design is described for control and readout of the two inertially-coupled modes of a vibratory gyroscope or the two uncoupled modes of a dual beam vibratory accelerometer. Like the evolution of the high yield, high performance operational amplifier, single, dual, or quad channel URC ASIC configurations are anticipated to implement single-axis, two-axis, or three-axis IMU or INS. Our first URC ASIC has been submitted for fabrication in a 4.1mmx4.1mm, 180nm CMOS die. Each URC additionally provides digitally selectable analog gains and two DACs per channel with up to 30V range for tuning of residual machining errors, on-line precision quadrature or amplitude control. A low power digital demodulator is being developed with FPGA for subsequent CMOS integration. With this universal ASIC architecture and exemplary wafer-level-packaged, high Q MEMS in-plane resonators, a compact 2D and 3D Navigation System on Chip (NSoC™) architecture is enabled to increase the production scale and radically reduce the cost, size, weight, and power of electronics and systems for numerous existing and future highly compact MEMS inertial navigation applications. The ASIC design and its application to CVG and DRBA control, will be discussed including the electronics trades, and analog breadboard developments supporting its design.