Single-axis acceleration sensor reading circuit based on capacitance charge converter

Abstract

The utility model discloses a single-axis acceleration sensor reading circuit based on a capacitance charge converter, and the circuit comprises a reading module which is used for reading a charge signal of a sensor; the signal conversion module is used for converting the charge signal into a voltage signal; the filtering and amplifying module is used for filtering and amplifying the voltage signal; wherein the reading module, the signal conversion module and the filtering and amplifying module are electrically connected in sequence. The single-axis acceleration sensor reading circuit based on the capacitance charge converter is simple in structure and convenient to use, charges are converted into voltages through cooperative arrangement of the reading module, the signal conversion module and the filtering and amplifying module, and different charges are converted into different voltage signals within a set range, so that the single-axis acceleration sensor reading circuit based on the capacitance charge converter is more accurate in reading. Therefore, an acceleration signal of a sensor is converted from a physical quantity to a voltage signal.

Description

Technical Field

[0001] The utility model relates to the technical field of single-axis acceleration sensors, in particular to a single-axis acceleration sensor reading circuit based on a capacitor charge converter. Background Art

[0002] The analog single-axis accelerometer is a sensor based on microelectromechanical system (MEMS) technology that can measure the acceleration of an object in a single axis. MEMS accelerometers are usually composed of microelectromechanical sensors and signal processing circuits. Microelectromechanical sensors usually consist of a tiny mass block and a spring, with the mass block located at one end of the spring and the other end fixed to the base. When the accelerometer is subjected to acceleration, the mass block will be displaced relative to the spring, and the displacement is proportional to the magnitude of the acceleration. This displacement signal will be converted into charge. In CV converters, the commonly used charge conversion principle is to achieve voltage conversion by integrating the input charge. Specifically, the input signal is integrated through a capacitor to form a charge. This charge can be output as a voltage signal or used to control the behavior of other electronic devices. In the past, the general way of circuits was to use ASICs to read the charge signal of mems, and the internal circuit was very complicated.

[0003] Based on the above situation, the utility model proposes a single-axis acceleration sensor reading circuit based on a capacitive charge converter, which can effectively solve the above problems. Utility Model Content

[0004] The purpose of the utility model is to provide a uniaxial acceleration sensor reading circuit based on a capacitive charge converter. The uniaxial acceleration sensor reading circuit based on a capacitive charge converter of the utility model has a simple structure and is easy to use. Through the coordinated setting between the reading module, the signal conversion module and the filtering and amplification module, the charge is converted into a voltage, and within a set range, different charges are converted into different voltage signals, thereby converting the acceleration signal of a sensor from a physical quantity into a voltage signal, thereby calculating the acceleration of the object.

[0005] The utility model is realized by the following technical solutions:

[0006] A single-axis acceleration sensor reading circuit based on a capacitive charge converter, comprising:

[0007] A reading module, used for reading the charge signal of the sensor;

[0008] A signal conversion module, used to convert the charge signal into a voltage signal;

[0009] A filtering and amplifying module, used for filtering and amplifying voltage signals;

[0010] Wherein, the reading module, the signal conversion module, and the filtering and amplifying module are electrically connected in sequence.

[0011] The purpose of the utility model is to provide a uniaxial acceleration sensor reading circuit based on a capacitive charge converter. The uniaxial acceleration sensor reading circuit based on a capacitive charge converter of the utility model has a simple structure and is easy to use. Through the coordinated setting between the reading module, the signal conversion module and the filtering and amplification module, the charge is converted into a voltage, and within a set range, different charges are converted into different voltage signals, thereby converting the acceleration signal of a sensor from a physical quantity into a voltage signal, thereby calculating the acceleration of the object.

[0012] Preferably, the reading module includes a first connector J2, a first capacitor C1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8;

[0013] The Det+ pin of the first connector J2 is electrically connected to one end of the first resistor R1, the fifth resistor R5, and the seventh resistor R7 respectively; the other end of the first resistor R1 is electrically connected to the GND pin of the first connector J2, one end of the second resistor R2, one end of the third resistor R3, and one end of the first capacitor C1 respectively; the other end of the fifth resistor R5 is electrically connected to the other end of the third resistor R3, one end of the fourth resistor R4, and the other end of the first capacitor C1 respectively; the other end of the seventh resistor R7 is electrically connected to one end of the sixth resistor R6; the other end of the sixth resistor R6 is electrically connected to the Det- pin of the first connector J2, the other end of the second resistor R2, and the other end of the fourth resistor R4 respectively; and the Com pin of the first connector J2 is electrically connected to one end of the eighth resistor R8.

[0014] Preferably, the signal conversion module includes a first operational amplifier U1A, a first diode D1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11;

[0015] The other end of the eighth resistor R8 is electrically connected to the cathode of the first diode D1, one end of the ninth resistor R9, pin 2 of the first operational amplifier U1A, one end of the second capacitor C2, one end of the third capacitor C3, and one end of the tenth resistor R10, respectively; the anode of the first diode D1 is electrically connected to the other end of the ninth resistor R9, one end of the fourth capacitor C4, and pin 3 of the first operational amplifier U1A, the other end of the second capacitor C2 is electrically connected to the other end of the third capacitor C3, the other end of the tenth resistor R10, one end of the eleventh resistor R11, and pin 1 of the first operational amplifier U1A, and the other end of the eleventh resistor R11 is electrically connected to pin 4 of the first operational amplifier U1A.

[0016] Preferably, the filtering and amplifying module includes a second connector J1, a second operational amplifier U1B, a fifth capacitor C5, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, and a sixteenth resistor R16;

[0017] One end of the fourteenth resistor R14 is electrically connected to pin 1 of the first operational amplifier U1A, and the other end is electrically connected to pin 6 of the second operational amplifier U1B, one end of the fifth capacitor C5, and one end of the fifteenth resistor R15. Pin 5 of the second operational amplifier U1B is electrically connected to one end of the twelfth resistor R12 and one end of the thirteenth resistor R13. Pin 7 of the second operational amplifier U1B is electrically connected to the other end of the fifth capacitor C5, the other end of the fifteenth resistor R15, and one end of the sixteenth resistor R16. The other end of the sixteenth resistor R16 is electrically connected to the VOUT pin of the second connector J1.

[0018] Compared with the prior art, the utility model has the following advantages and beneficial effects:

[0019] The utility model discloses a single-axis acceleration sensor reading circuit structure based on a capacitive charge converter, which is simple in structure and easy to use. The charge is converted into voltage through the coordinated setting among the reading module, the signal conversion module and the filtering and amplifying module, and different charges are converted into different voltage signals within a set range, thereby converting the acceleration signal of a sensor from a physical quantity into a voltage signal, thereby calculating the acceleration magnitude of the object. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a circuit schematic diagram of the utility model. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the technical solution of the utility model, the preferred implementation scheme of the utility model is described below in conjunction with specific embodiments. However, it should be understood that the drawings are only used for illustrative purposes and cannot be understood as a limitation on this patent. In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. The positional relationship described in the drawings is only used for illustrative purposes and cannot be understood as a limitation on this patent.

[0022] Embodiment 1:

[0023] like Figure 1 As shown, the utility model provides a single-axis acceleration sensor reading circuit based on a capacitive charge converter, comprising:

[0024] A reading module, used for reading the charge signal of the sensor;

[0025] A signal conversion module, used to convert the charge signal into a voltage signal;

[0026] A filtering and amplifying module, used for filtering and amplifying voltage signals;

[0027] Wherein, the reading module, the signal conversion module, and the filtering and amplifying module are electrically connected in sequence.

[0028] Embodiment 2:

[0029] like Figure 1 As shown, the utility model provides a single-axis acceleration sensor reading circuit based on a capacitive charge converter, comprising:

[0030] A reading module, used for reading the charge signal of the sensor;

[0031] A signal conversion module, used to convert the charge signal into a voltage signal;

[0032] A filtering and amplifying module, used for filtering and amplifying voltage signals;

[0033] Wherein, the reading module, the signal conversion module, and the filtering and amplifying module are electrically connected in sequence.

[0034] The reading module includes a first connector J2, a first capacitor C1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8;

[0035] The Det+ pin of the first connector J2 is electrically connected to one end of the first resistor R1, the fifth resistor R5, and the seventh resistor R7 respectively; the other end of the first resistor R1 is electrically connected to the GND pin of the first connector J2, one end of the second resistor R2, one end of the third resistor R3, and one end of the first capacitor C1 respectively; the other end of the fifth resistor R5 is electrically connected to the other end of the third resistor R3, one end of the fourth resistor R4, and the other end of the first capacitor C1 respectively; the other end of the seventh resistor R7 is electrically connected to one end of the sixth resistor R6; the other end of the sixth resistor R6 is electrically connected to the Det- pin of the first connector J2, the other end of the second resistor R2, and the other end of the fourth resistor R4 respectively; and the Com pin of the first connector J2 is electrically connected to one end of the eighth resistor R8.

[0036] Further, in another embodiment, the signal conversion module includes a first operational amplifier U1A, a first diode D1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11;

[0037] The other end of the eighth resistor R8 is electrically connected to the cathode of the first diode D1, one end of the ninth resistor R9, pin 2 of the first operational amplifier U1A, one end of the second capacitor C2, one end of the third capacitor C3, and one end of the tenth resistor R10, respectively; the anode of the first diode D1 is electrically connected to the other end of the ninth resistor R9, one end of the fourth capacitor C4, and pin 3 of the first operational amplifier U1A, the other end of the second capacitor C2 is electrically connected to the other end of the third capacitor C3, the other end of the tenth resistor R10, one end of the eleventh resistor R11, and pin 1 of the first operational amplifier U1A, and the other end of the eleventh resistor R11 is electrically connected to pin 4 of the first operational amplifier U1A.

[0038] Further, in another embodiment, the filtering and amplifying module includes a second connector J1, a second operational amplifier U1B, a fifth capacitor C5, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, and a sixteenth resistor R16;

[0039] One end of the fourteenth resistor R14 is electrically connected to pin 1 of the first operational amplifier U1A, and the other end is electrically connected to pin 6 of the second operational amplifier U1B, one end of the fifth capacitor C5, and one end of the fifteenth resistor R15. Pin 5 of the second operational amplifier U1B is electrically connected to one end of the twelfth resistor R12 and one end of the thirteenth resistor R13. Pin 7 of the second operational amplifier U1B is electrically connected to the other end of the fifth capacitor C5, the other end of the fifteenth resistor R15, and one end of the sixteenth resistor R16. The other end of the sixteenth resistor R16 is electrically connected to the VOUT pin of the second connector J1.

[0040] A 3.3v system was built using discrete components, which can convert charge into voltage and, within a set range, convert different charges into different voltage signals, thereby converting a sensor's acceleration signal from a physical quantity into a voltage signal.

[0041] This circuit uses a constant 3.3V to load one end of the internal capacitor DET+ of the MEMS, connects DET- to the ground, and then reads the change in capacitance value at the COM end due to changes in position and acceleration, converts this change into voltage, and compares and amplifies the output.

[0042] This signal processing circuit usually consists of an amplifier, a filter, and an analog-to-digital converter. The amplifier is used to increase the amplitude of the sensor output signal, the filter is used to remove high-frequency noise and clutter, and the analog-to-digital converter converts the analog voltage signal into a digital signal for processing by a computer or microcontroller.

[0043] By measuring the magnitude of the output voltage signal, the magnitude of the acceleration to which the object is subjected can be calculated. Typically, the output voltage signal of an accelerometer is linearly related to the acceleration to which the object is subjected. For example, a typical accelerometer may have a sensitivity of 0.5mV / g within the ±2g range, which means that when the object is subjected to an acceleration of 1g in that axis, the sensor output voltage will increase by 0.5mV.

[0044] According to the description and drawings of the present invention, those skilled in the art can easily manufacture or use the single-axis acceleration sensor reading circuit based on a capacitive charge converter of the present invention, and can produce the positive effects recorded in the present invention.

[0045] Unless otherwise specified, in the present invention, the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicating orientation or positional relationships are based on the orientation or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the orientation or positional relationship in the present invention are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood in conjunction with the drawings and according to specific circumstances.

[0046] Unless otherwise specified and limited, in the present invention, the terms "disposed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A uniaxial acceleration sensor reading circuit based on a capacitive charge converter, characterized in that: include: A reading module, used for reading the charge signal of the sensor; A signal conversion module, used to convert the charge signal into a voltage signal; A filtering and amplifying module, used for filtering and amplifying voltage signals; Wherein, the reading module, the signal conversion module, and the filtering and amplifying module are electrically connected in sequence; The reading module includes a first connector J2, a first capacitor C1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8; The Det+ pin of the first connector J2 is electrically connected to the first resistor R1, the fifth resistor R5, and one end of the seventh resistor R7, respectively; the other end of the first resistor R1 is electrically connected to the GND pin of the first connector J2, one end of the second resistor R2, one end of the third resistor R3, and one end of the first capacitor C1, respectively; the other end of the fifth resistor R5 is electrically connected to the other end of the third resistor R3, one end of the fourth resistor R4, and the other end of the first capacitor C1, respectively; the other end of the seventh resistor R7 is electrically connected to one end of the sixth resistor R6, and the other end of the sixth resistor R6 is electrically connected to the Det- pin of the first connector J2, the other end of the second resistor R2, and the other end of the fourth resistor R4, respectively; the Com pin of the first connector J2 is electrically connected to one end of the eighth resistor R8; The signal conversion module includes a first operational amplifier U1A, a first diode D1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11; The other end of the eighth resistor R8 is electrically connected to the cathode of the first diode D1, one end of the ninth resistor R9, pin 2 of the first operational amplifier U1A, one end of the second capacitor C2, one end of the third capacitor C3, and one end of the tenth resistor R10, respectively; the anode of the first diode D1 is electrically connected to the other end of the ninth resistor R9, one end of the fourth capacitor C4, and pin 3 of the first operational amplifier U1A, respectively; the other end of the second capacitor C2 is electrically connected to the other end of the third capacitor C3, the other end of the tenth resistor R10, one end of the eleventh resistor R11, and pin 1 of the first operational amplifier U1A, and the other end of the eleventh resistor R11 is electrically connected to pin 4 of the first operational amplifier U1A; The filtering and amplifying module includes a second connector J1, a second operational amplifier U1B, a fifth capacitor C5, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, and a sixteenth resistor R16; One end of the fourteenth resistor R14 is electrically connected to pin 1 of the first operational amplifier U1A, and the other end is electrically connected to pin 6 of the second operational amplifier U1B, one end of the fifth capacitor C5, and one end of the fifteenth resistor R15. Pin 5 of the second operational amplifier U1B is electrically connected to one end of the twelfth resistor R12 and one end of the thirteenth resistor R13. Pin 7 of the second operational amplifier U1B is electrically connected to the other end of the fifth capacitor C5, the other end of the fifteenth resistor R15, and one end of the sixteenth resistor R16. The other end of the sixteenth resistor R16 is electrically connected to the VOUT pin of the second connector J1.

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