Abstract:The silicon micro gyroscope consists of a gyroscope structure and a measurement and control circuit. With the improvement of analog interface circuits, the improvement of gyroscope performance mainly relies on the measurement and control and compensation algorithms in digital circuits. At present, the measurement and control circuits of silicon micro gyroscopes are developing towards chip based direction. In order to accelerate the process of chip based measurement and control circuits of silicon micro gyroscopes, Verilog HDL is used to design AGC and PLL for closed-loop control of gyroscope amplitude and phase, and Coriolis force balance for closed-loop detection. An orthogonal correction closed-loop was designed to address the orthogonal errors caused by processing. Based on the influence of temperature on the gyroscope, linear compensation was applied to the scale factor and BP neural network compensation was applied to zero bias. The experimental results show that under this control system, the relative stability of AGC is 124ppm, the relative stability of PLL is 79.1ppm, and the zero bias stability at room temperature is 2.9 o/h; The zero bias stability before compensation is 17.7 o/h within the temperature range of 0℃ to 65℃, and the zero bias stability after compensation is 9.1 o/h. The temperature sensitivity of the scaling factor is reduced by one order of magnitude. The research results not only improve the performance of silicon micro gyroscopes, but also lay a solid foundation for gyro ASIC design.
