Digital closed-loop scheme can reduce precision loss in analog to digital（ A /D） conversion of analog servo scheme

and quantization error is one of the important factors which influence system precision of digital closed-loop quartz flex accelerometer（ DCL-accelerometer）. Working principle of DCL-accelerometer detecting system is introduced

and digits selection criteria of AD

DA bit is discussed

i. e

based on existing hardware detection circuit

use AD

DA dropping method to analyze closed-loop system precision influenced by quantization error from software aspect. Build up digital closed-loop experimental system

experimental results show that in a certain range

as AD

DA bits dropping

effect of quantization error is increased while closed-loop system precision is reduced

which coincides with the theoretical analysis and provides necessary theoretical guidance and experimental basis for improvement of precision of the accelerometer.