In order to realize the high precision

digital and miniaturization of MEMS gyroscope

which is the application requirements of the field of inertial navigation and measurement

this paper designs and implements a practical MEMS gyroscope interface circuit which adopts the process of dual-chip integration

integrated based on N-well CMOS process of 0.5 μm. The paper introduces the design of analog front-end circuit which contains closed-loop self-exciting driving structure based on high-frequency carrier and low noise differential sensitive detection circuit. The high frequency signal modulates the sensitive signal to the high frequency and adds the flicker noise. Through the phase sensitive demodulation and low-pass filtering

the low noise analog angular speed output is obtained. The circuit converts analog signal into digital signal by an integrated high-resolution sigma delta four-order single ring one bit ADC

achieving an interface circuit of silicon gyroscope with digital output. Test results show that the dynamic range of the modulator which bandwidth and scale factor are 60 Hz and 46.45 LSB/(°)·s-1

respectively

is up to 130 dB

and the measuring range of gyroscope is ±200 °/s. The linearity of the modulator with the noise of 0.004 (°)·s-1/Hz1/2 is 340×10-6

and the stability of the zero bias is 3.4 °/h. It enables miniaturization

low cost and precise digital output of angular speed through integrated circuit. Comparison of the test results with other related research also confirms that the structure can achieve good performance.