The Research Of High Precision Accelerometer Acquisition Unit And Key Component

The accelerometer is the important inertia sensitive component in the inertial navigation system, it outputs signal which is certain functional relation to the movement of vector. Accelerometer's output precision immediate influence inertial navigation system's precision. High accuracy quartz flexible accelerometer generally outputs analog current signal. The accelerometer gathers circuit's function is the converting analog electronic signal to digital signal, and has as far as possible small degradation of accelerometer's performance.This article has studied the high accuracy accelerometer gathering circuit as well as the essential component which restricts its performance. The target of unit is: the temperature coefficient of zero offset at 1uV/℃, the excursion during 24 hours at 2uV and the noise at 1uVrms@100Hz/s. The high accuracy accelerometer gathering circuit's resolution will be to the microvolt and nanoampere rank. It needed to pay extraordinary attention to the parasitic which may be neglected in some circuits. Otherwise, system's performance can not be guaranteed. This article elaborates emphatically electric circuit's design as well as essential component's choice. In high accuracy analogous circuit, system performance peak value is often decided by single or minority essential component's performance. In order to achieve as far as good performance, it needs to accurate calculate affects of all of the components, and chooses carefully according to the calculation. After completing the circuit design and the manufacture, carried on the massive tests to system's performance. The test result had indicated that the system has achieved the performance which initially established.This article has also conducted the research to the main restriction system performance's part - - A/D converter. Study focuses on the factors which limited enhancement performance, and understanding limiting of circuit performance better.By study about accelerometer gathering circuit, I have know how to design high performance analog-digital mixing circuit, accelerometer's principle as well as Sigma-Delta A/D converter's basic principle, have built the good foundation for the further work and the study.