IEPE circuit

Abstract

The utility model discloses an IEPE circuit comprising a signal detection unit and a power supply unit, the power supply unit supplies power to the signal detection unit, the signal detection unit comprises a charge amplifier and a transient surge current suppression unit, the transient surge current suppression unit is connected with the charge amplifier in parallel, the power supply unit comprises a constant current source, and the constant current source is connected with the charge amplifier in parallel. And the constant current source supplies power to the charge amplifier. The interference suppression circuit is suitable for the IEPE sensor, can effectively suppress interference, and ensures the effectiveness of an output signal of the IEPE sensor.

Description

Technical Field

[0001] The utility model relates to electronic circuit technology, and particularly to an IEPE circuit. Background Art

[0002] IEPE is an acceleration sensor with a built-in charge amplifier or voltage amplifier. IEPE is the abbreviation of piezoelectric integrated circuit. The IEPE sensor is based on the piezoelectric effect. When the piezoelectric element is subjected to an external force, a weak charge signal will be generated. Since the amount of electricity generated by the piezoelectric element is very small, the electrical signal generated by the sensor is easily affected by noise interference, and sensitive electronic devices are required to amplify and condition the signal. Content of the Utility Model

[0003] To meet the above requirements, the utility model aims to provide an IEPE circuit, which can effectively suppress interference and ensure the effectiveness of the output signal of the IEPE sensor.

[0004] To achieve the above object, the technical solution adopted by the utility model is as follows:

[0005] An IEPE circuit includes a signal detection unit and a power supply unit. The power supply unit supplies power to the signal detection unit. The signal detection unit includes a charge amplifier and a transient surge current suppression unit. The transient surge current suppression unit is connected in parallel with the charge amplifier. The power supply unit includes a constant current source, and the constant current source supplies power to the charge amplifier.

[0006] Preferably, the charge amplifier includes a field effect transistor Q1. One end of a resistor R1 and one end of a capacitor C1 are connected to the gate of the field effect transistor Q1. The source of the field effect transistor Q1 is connected to the current output end of the constant current source. One end of a resistor R2 is connected to the drain of the field effect transistor Q1. The other ends of the resistor R1, the capacitor C1, and the resistor R2 are all connected to the current input end of the constant current source.

[0007] Preferably, the transient surge current suppression unit includes an N-channel depletion type field effect transistor Q2 and a P-channel depletion type field effect transistor Q3. The source of the N-channel depletion type field effect transistor Q2 is connected to the source of the P-channel depletion type field effect transistor Q3, the anode of a voltage stabilizing diode D1, and the cathode of a voltage stabilizing diode D2. The cathode of the voltage stabilizing diode D1 is connected to the drain of the N-channel depletion type field effect transistor Q2 and the gate of the P-channel depletion type field effect transistor Q3. The anode of the voltage stabilizing diode D2 is connected to the gate of the N-channel depletion type field effect transistor Q2 and one end of a resistor R3. The other end of the resistor R3 is connected to the drain of the P-channel depletion type field effect transistor Q3;

[0008] The drain of the N-channel depletion type field effect transistor Q2 is connected to the source of the field effect transistor Q1, and the drain of the P-channel depletion type field effect transistor Q3 is connected to the other end of the resistor R2.

[0009] Preferably, the constant current source includes a constant current diode D3.

[0010] Preferably, the anode of the constant current diode D3 is connected to the high potential output terminal of the DC power supply unit, the cathode of the constant current diode D3 is the current output terminal of the constant current source, and the low potential output terminal of the DC power supply unit is the current input terminal of the constant current source.

[0011] Further, the anode of the constant current diode D3 is connected to one end of a capacitor C2, the other end of the capacitor C2 is connected to one end of a resistor R4, and the other end of the resistor R4 is connected to the low potential output terminal of the DC power supply unit.

[0012] Preferably, the DC power supply unit is a battery pack or an AC / DC DC power supply.

[0013] The working pressure of the present utility model is as follows:

[0014] The constant current source supplies power to the charge amplifier. The two ends of a capacitor C1 are connected to a piezoelectric element for storing the charge generated by the piezoelectric element. Then, after being amplified by a charge amplifier composed of a field effect transistor Q1, it is converted into a voltage and forms a certain bias voltage, and an AC signal is output through the capacitor C2. Among them, the transient surge current suppression unit is used to suppress the spike interference caused by factors such as the environment, effectively protecting the output signal of the IEPE sensor and the IEPE sensor itself.

[0015] The beneficial effects of the present utility model are as follows:

[0016] 1. The present utility model is applicable to IEPE sensors, can effectively obtain the charge change of the piezoelectric element, and thus accurately obtain the IEPE sensor signal.

[0017] 2. The present utility model can suppress the spike interference caused by factors such as the environment, effectively protecting the output signal of the IEPE sensor and the IEPE sensor itself.

[0018] 3. The present utility model has a simple structure and reliable performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is the circuit schematic diagram of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] In order to make the purpose, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0021] This embodiment discloses an IEPE circuit, which includes a signal detection unit and a power supply unit. The power supply unit supplies power to the signal detection unit. The signal detection unit includes a charge amplifier and a transient surge current suppression unit. The transient surge current suppression unit is connected in parallel with the charge amplifier. The power supply unit includes a constant current source, and the constant current source supplies power to the charge amplifier. Specifically:

[0022] As Figure 1 shown, the charge amplifier includes a field effect transistor Q1. One end of a resistor R1 and one end of a capacitor C1 are connected to the gate of the field effect transistor Q1. The source of the field effect transistor Q1 is connected to the current output end of the constant current source. The drain of the field effect transistor Q1 is connected to one end of a resistor R2. The other ends of the resistor R1, the capacitor C1, and the resistor R2 are all connected to the current input end of the constant current source. The transient surge current suppression unit includes an N-channel depletion type field effect transistor Q2 and a P-channel depletion type field effect transistor Q3. The source of the N-channel depletion type field effect transistor Q2 is connected to the source of the P-channel depletion type field effect transistor Q3, the anode of a voltage stabilizing diode D1, and the cathode of a voltage stabilizing diode D2. The cathode of the voltage stabilizing diode D1 is connected to the drain of the N-channel depletion type field effect transistor Q2 and the gate of the P-channel depletion type field effect transistor Q3. The anode of the voltage stabilizing diode D2 is connected to the gate of the N-channel depletion type field effect transistor Q2 and one end of a resistor R3. The other end of the resistor R3 is connected to the drain of the P-channel depletion type field effect transistor Q3. The drain of the N-channel depletion type field effect transistor Q2 is connected to the source of the field effect transistor Q1, and the drain of the P-channel depletion type field effect transistor Q3 is connected to the other end of the resistor R2.

[0023] The constant current source includes a constant current diode D3. The anode of the constant current diode D3 is connected to the high potential output end of the DC power supply unit. The cathode of the constant current diode D3 is the current output end of the constant current source. The low potential output end of the DC power supply unit is the current input end of the constant current source. The anode of the constant current diode D3 is connected to one end of a capacitor C2. The other end of the capacitor C2 is connected to one end of a resistor R4. The other end of the resistor R4 is connected to the low potential output end of the DC power supply unit.

[0024] Among them, the DC power supply unit BT1 can adopt a battery pack or other DC power sources such as an AC / DC DC power supply.

[0025] Certainly, the present utility model may also have other various embodiments. Without departing from the spirit and essence of the present utility model, those skilled in the art can make various corresponding changes and deformations according to the present utility model, but these corresponding changes and deformations should all fall within the protection scope of the appended claims of the present utility model.

Claims

1. An IEPE circuit, comprising a signal detection unit and a power supply unit, wherein the power supply unit supplies power to the signal detection unit, wherein: The signal detection unit comprises a charge amplifier and a transient surge current suppression unit, wherein the transient surge current suppression unit is connected in parallel with the charge amplifier, and the power supply unit comprises a constant current source, wherein the constant current source supplies power to the charge amplifier.

2. The IEPE circuit according to claim 1, characterized in that: The charge amplifier includes a field effect transistor Q1, a gate of the field effect transistor Q1 is connected to one end of a resistor R1 and one end of a capacitor C1, a source of the field effect transistor Q1 is connected to a current output end of a constant current source, a drain of the field effect transistor Q1 is connected to one end of a resistor R2, and the other end of the resistor R1, the other end of the capacitor C1, and the other end of the resistor R2 are all connected to a current input end of the constant current source.

3. The IEPE circuit according to claim 2, characterized in that: The transient surge current suppression unit includes an N-channel depletion-type field effect transistor Q2 and a P-channel depletion-type field effect transistor Q3, the source of the N-channel depletion-type field effect transistor Q2 is connected to the source of the P-channel depletion-type field effect transistor Q3, the anode of the voltage-stabilizing diode D1, and the cathode of the voltage-stabilizing diode D2, the cathode of the voltage-stabilizing diode D1 is connected to the drain of the N-channel depletion-type field effect transistor Q2 and the gate of the P-channel depletion-type field effect transistor Q3, the anode of the voltage-stabilizing diode D2 is connected to the gate of the N-channel depletion-type field effect transistor Q2 and one end of the resistor R3, and the other end of the resistor R3 is connected to the drain of the P-channel depletion-type field effect transistor Q3; The drain of the N-channel depletion-type field effect transistor Q2 is connected to the source of the field effect transistor Q1 , and the drain of the P-channel depletion-type field effect transistor Q3 is connected to the other end of the resistor R2 .

4. The IEPE circuit according to claim 2 or 3, characterized in that: The constant current source includes a constant current diode D3.

5. The IEPE circuit according to claim 4, characterized in that: The anode of the constant current diode D3 is connected to the high potential output end of the DC power supply unit, the cathode of the constant current diode D3 is the current output end of the constant current source, and the low potential output end of the DC power supply unit is the current input end of the constant current source.

6. The IEPE circuit according to claim 5, characterized in that: The anode of the constant current diode D3 is connected to one end of the capacitor C2, the other end of the capacitor C2 is connected to one end of the resistor R4, and the other end of the resistor R4 is connected to the low potential output end of the DC power supply unit.

7. The IEPE circuit according to claim 5, characterized in that: The DC power supply unit is a battery pack or an AC / DC direct current power supply.

Images