High-order continuous low-pass sigma-delta closed-loop control circuit of micro-mechanical accelerometer

The invention discloses a high-order continuous low-pass sigma-delta closed-loop control circuit of a micro-mechanical accelerometer, which belongs to the field of guidance or control devices using Coriolis effect. The circuit comprises a prepositive fully-differential charge amplifier 2, a high-pass filter 3, a diode 4, a low-pass filter 5, a fully-differential amplifying circuit 6, a phase compensation circuit 7, an integrating circuit I 8, an integrating circuit II 9, an integrating circuit III 10, an integrating circuit IV 11, a digital conversion circuit 12, and an analogue switch 13. The high-order continuous low-pass sigma-delta closed-loop control circuit of the micro-mechanical accelerometer has the following beneficial effects: the integrating circuit I 8, the integrating circuit II 9, the integrating circuit III 10 and the integrating circuit IV 11 in the closed-loop, together with the micro-mechanical accelerometer, can form a six-order noisy shaping filter, so that the noises of the system are suppressed, and the SNR (signal to noise ratio) is improved.