Sensing device

Abstract

The invention relates to a sensing device. The sensing device comprises a micro electro mechanical sensor and an adjustable amplifier; the micro electro mechanical sensor is used for generating an input signal according to environmental change; the adjustable amplifier is provided with a first input end, a second input end, a third input end, a fourth input end and a first output end; the first input end is electrically connected to the micro electro mechanical sensor, and used for receiving the input signal; the second input end is electrically connected to a first signal end, and used for receiving a first common-mode signal; the third input end is electrically connected to the first output end; and the fourth input end is electrically connected to a second signal end, wherein the potential of the first output signal of the first output end of the adjustable amplifier is associated with the potential of the input signal, the first signal end and the second signal end. According to the sensing device disclosed by the invention, with the help of the fact that the micro electro mechanical sensor is directly coupled to the adjustable amplifier, the effect of reducing current can be achieved through the high-impedance-input adjustable amplifier as the input interface of the micro electro mechanical sensor; furthermore, occupation of a circuit (source follower) can be saved; and thus, the available area of the circuit can be increased.

Description

technical field [0001] The invention relates to a sensing device, in particular to a sensing device applied to micro-electromechanical devices. Background technique [0002] With the development of science and technology and people's emphasis on audio-visual entertainment, the application of digital microphones is becoming more and more popular. Whether it is in the public domain (such as company meetings, public exhibitions), or in the private domain (such as personal audio-visual rooms), the use of digital microphones is indispensable. Generally speaking, the internal circuit of a digital microphone usually has a micro electro mechanical system (Micro Electro Mechanical Systems, MEMS) and an application specific integrated circuit (Application Specific Integrated Circuit, ASIC). After the electrical signal is obtained through the microelectromechanical (MEMS) device, the source follower (Source Follower), programmable gain amplifier (Programmable Gain Amplifier, PGA) and ...

AI Technical Summary

Problems solved by technology

However, this circuit architecture (with source follower, programmable gain amplifier and analog-to-digital converter) consumes a lot of current and causes a circuit space occupation

Images