An air pressure detection signal processing circuit for a blood analyzer

Abstract

A pressure detection signal processing circuit for a blood analyzer, a positive pressure circuit and a negative pressure circuit of the same structure, wherein the positive pressure circuit includes a positive pressure input terminal XM1, which is connected to the voltage follower U1-C, and the output end is also connected to the inverting terminal of the operational amplifier U1-B through a resistor R6. The operational amplifier U1-B is connected to the positive pressure input terminal XM1, and its output end is connected to the operational amplifier U1-A through a resistor R8, and its output end is connected to a variable resistor R20; the non-phase terminal of the operational amplifier U1-A is connected to the variable resistor R20, and is also connected to the inverting terminal of the operational amplifier U1-B through a resistor R1 5 is connected to a variable resistor R12, the second voltage is connected to the variable resistor R12 through a resistor R10, the other end of the variable resistor R12 is grounded through a resistor R16, the second voltage is connected to the variable resistor R13 through a resistor R11, the variable resistor R13 is grounded through a resistor R17, the variable resistor R14 is further connected to the non-inverting terminal of the operational amplifier U1-D through the resistor R14, the inverting terminal is connected to the output terminal of the operational amplifier U1-D through a resistor R19, and the output terminal is connected to the variable resistor R20, and the variable resistor R20 outputs the voltage through pin 1 of the output terminal J2.

Description

Technical Field

[0001] The present invention relates to the field of blood analyzers, and in particular to an air pressure detection signal processing circuit for a blood analyzer. Background Art

[0002] Air compressors are widely used industrial machines, available in many varieties, and are indispensable equipment for many industrial manufacturers. They convert the mechanical energy of a prime mover into gas pressure energy, acting as compressed air generators. They are the core of the air supply system, responsible for providing air to all factory components (such as pneumatic valves). They provide a continuous supply of compressed air at a constant pressure, enabling processes requiring it. Blood analyzers also require such a compressor.

[0003] In the prior art, air compressors use valve switches to control air. When the pressure reaches a certain standard value, the pressure is released. When the pressure drops below a certain standard, gas is added again. During the above-mentioned pressure release and pressurization process, a large amount of electricity is consumed. If the signal is not processed properly during this process, it will lead to technical problems such as slow adjustment speed, low accuracy, and unstable output pressure. Currently, a gas pressure sensor is usually used to detect the gas pressure. The pressure data detected by the sensor is then converted into an electrical signal through its internal circuit and output from the output end of the pressure sensor. The output signal is then amplified and processed by the back-end processing unit. Such signal processing technology often leads to the entry of various interference sources such as common-mode interference, which affects the signal quality and makes it difficult to achieve relatively high accuracy. The actual pressure value output by the air compressor is often quite different from the value displayed on the instrument. Moreover, it lacks flexibility in gas pressure debugging and is inconvenient to use. Summary of the Invention

[0004] To solve the above problems, the present technical solution provides an air pressure detection signal processing circuit for a blood analyzer.

[0005] To achieve the above purpose, the technical solution is as follows:

[0006] A pressure detection signal processing circuit for a blood analyzer includes a positive pressure input terminal XM1, wherein pin 2 of the positive pressure input terminal XM1 inputs a first voltage, pin 3 is connected to the non-inverting terminal of a voltage follower U1-C, the inverting terminal of the voltage follower U1-C is connected to a second voltage via a resistor R4, a resistor R5 is connected between the inverting terminal and the output terminal of the voltage follower U1-C, and the output terminal is further connected to the inverting terminal of an op amp U1-B via a resistor R6, the non-inverting terminal of the op amp U1-B is connected to pin 5 of the positive pressure input terminal XM1, the output terminal is connected to the inverting terminal of the op amp U1-A via a resistor R8, and the output terminal is connected to a variable resistor R20;

[0007] The non-phase terminal of the operational amplifier U1-A is connected to the variable resistor R20 through a resistor R18, and is also connected to the variable resistor R12 through a resistor R15. The second voltage is connected to the variable resistor R12 through a resistor R10, and the other end of the variable resistor R12 is grounded through a resistor R16. The second voltage is connected to the variable resistor R13 through a resistor R11, and the variable resistor R13 is grounded through a resistor R17. The variable resistor R14 is also connected to the non-phase terminal of the operational amplifier U1-D through a resistor R14, and its inverting terminal is connected to its output terminal through a resistor R19, and the output terminal is connected to the variable resistor R20. The variable resistor R20 outputs through pin 1 of the output terminal J2;

[0008] It also includes a negative voltage input terminal XM2, pin 2 of the negative voltage input terminal XM2 also inputs the first voltage, its pin 5 is connected to the positive phase terminal of the voltage follower U2-C, its negative phase terminal is connected to the second voltage through a resistor R23, its output terminal is connected to the inverting terminal of the operational amplifier U2-B through a resistor R25, its positive phase terminal is connected to pin 3 of the negative voltage input terminal XM2, its output terminal is connected to the inverting terminal of the operational amplifier U2-A through a resistor R27, its output terminal is connected to a variable resistor R41, and the positive phase terminal of the operational amplifier U2-A is connected through Resistor R37 is connected to the variable resistor R41 and is also connected to the variable resistor R31 through resistor R34. The second voltage is grounded through resistor R29, variable resistor R31 and resistor R35 in sequence, and is also grounded through resistor R30, variable resistor R32 and resistor R36. The variable resistor R32 is connected to the non-inverting terminal of the operational amplifier U2-D through resistor R33, and its reverse end is connected to its output terminal through resistor R38, and is connected to the other end of the variable resistor R41. The variable resistor R41 is output through pin 3 of the output terminal J2.

[0009] In some embodiments, a capacitor C7 and a resistor R7 are provided between the inverting terminal and the output terminal of the operational amplifier U1-B, and a capacitor C13 and a resistor R26 are provided between the inverting terminal and the output terminal of the operational amplifier U2-B.

[0010] In some embodiments, the variable resistor R20 is connected to the output terminal J2 via a resistor R21 and a resistor R3, the resistor R21 is grounded via a resistor R22 and also grounded via a capacitor C9, and the resistor R3 is grounded via a capacitor C10;

[0011] The variable resistor R41 is connected to the output terminal J2 via a resistor R39 and a resistor R43 . The resistor R39 is grounded via a resistor R40 and also grounded via a capacitor C12 . The resistor R43 is grounded via a capacitor C11 .

[0012] The beneficial effects of this application are:

[0013] The signal generated by this application has higher accuracy and stronger anti-interference ability, and is easy and flexible to debug, with a wider debugging range. Finally, this application solution is more applicable, low-cost, and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments.

[0015] Figure 1 1 is a schematic diagram of the positive pressure circuit structure of an embodiment of the present invention;

[0016] Figure 2 2 is a schematic diagram of the negative voltage circuit structure of an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] Please refer to Figure 1-2 As shown, a pressure detection signal processing circuit for a blood analyzer is characterized by including a positive pressure input terminal XM1, wherein pin 2 of the positive pressure input terminal XM1 inputs a first voltage, pin 3 is connected to the non-inverting terminal of a voltage follower U1-C, the inverting terminal of the voltage follower U1-C is connected to a second voltage via a resistor R4, a resistor R5 is connected between the inverting terminal and the output terminal of the voltage follower U1-C, and the output terminal is further connected to the inverting terminal of an operational amplifier U1-B via a resistor R6, the non-inverting terminal of the operational amplifier U1-B is connected to pin 5 of the positive pressure input terminal XM1, the output terminal of the operational amplifier U1-B is connected to the inverting terminal of the operational amplifier U1-A via a resistor R8, and the output terminal of the operational amplifier U1-B is connected to a variable resistor R20;

[0019] The non-phase terminal of the operational amplifier U1-A is connected to the variable resistor R20 through a resistor R18, and is also connected to the variable resistor R12 through a resistor R15. The second voltage is connected to the variable resistor R12 through a resistor R10, and the other end of the variable resistor R12 is grounded through a resistor R16. The second voltage is connected to the variable resistor R13 through a resistor R11, and the variable resistor R13 is grounded through a resistor R17. The variable resistor R14 is also connected to the non-phase terminal of the operational amplifier U1-D through a resistor R14, and its inverting terminal is connected to its output terminal through a resistor R19, and the output terminal is connected to the variable resistor R20. The variable resistor R20 outputs through pin 1 of the output terminal J2;

[0020] It also includes a negative voltage input terminal XM2, pin 2 of the negative voltage input terminal XM2 also inputs the first voltage, its pin 5 is connected to the positive phase terminal of the voltage follower U2-C, its negative phase terminal is connected to the second voltage through a resistor R23, its output terminal is connected to the inverting terminal of the operational amplifier U2-B through a resistor R25, its positive phase terminal is connected to pin 3 of the negative voltage input terminal XM2, its output terminal is connected to the inverting terminal of the operational amplifier U2-A through a resistor R27, its output terminal is connected to a variable resistor R41, and the positive phase terminal of the operational amplifier U2-A is connected through Resistor R37 is connected to the variable resistor R41 and is also connected to the variable resistor R31 through resistor R34. The second voltage is grounded through resistor R29, variable resistor R31 and resistor R35 in sequence, and is also grounded through resistor R30, variable resistor R32 and resistor R36. The variable resistor R32 is connected to the non-inverting terminal of the operational amplifier U2-D through resistor R33, and its reverse end is connected to its output terminal through resistor R38, and is connected to the other end of the variable resistor R41. The variable resistor R41 is output through pin 3 of the output terminal J2.

[0021] Furthermore, a capacitor C7 and a resistor R7 are provided between the inverting terminal and the output terminal of the operational amplifier U1-B, and a capacitor C13 and a resistor R26 are provided between the inverting terminal and the output terminal of the operational amplifier U2-B.

[0022] Furthermore, the variable resistor R20 is connected to the output terminal J2 via the resistor R21 and the resistor R3, the resistor R21 is grounded via the resistor R22 and also grounded via the capacitor C9, and the resistor R3 is grounded via the capacitor C10;

[0023] The variable resistor R41 is connected to the output terminal J2 via a resistor R39 and a resistor R43 . The resistor R39 is grounded via a resistor R40 and also grounded via a capacitor C12 . The resistor R43 is grounded via a capacitor C11 .

[0024] refer to Figure 1The positive-pressure air output by the air compressor enters the pressure sensor through the air input port of the air pressure sensor. The pressure sensor detects the gas pressure and, after passing through the sensor's internal pressure-sensitive device and circuitry, outputs two signals at pins 3 and 5 of pressure sensor XM1, respectively. Signal XM1_3 enters voltage follower U1C via the non-inverting terminal. After passing through resistor R6, the output signal enters the inverting input of op amp U1B. It forms a differential operational amplifier circuit with signal XM1_5, which is input via the non-inverting terminal of op amp U1B. Phase compensation circuit C7 then performs phase compensation on the input signals, eliminating common-mode interference and compensating for phase. After passing through the follower and differential amplifier, the amplified signals XM1_3 and XM1_5 enter the inverting operational amplifier circuit formed by U1A through R8, achieving a 15x amplification factor. After phase compensation by C8, the amplified signals are output by U1A_1. The voltage sampled by rheostat R13 passes through resistor R14 and voltage follower U1D, and is input to the lower end of rheostat R20. By adjusting rheostat R13, the amplitude of the amplified output signal can be varied, thereby widening the amplitude range of the signal for subsequent processing. The amplified signal passes through sampling rheostat R20, where it is selected to be suitable for subsequent processing. The signal then flows through current-limiting resistor R21, the filter network formed by R22 and C9, and the low-pass filter circuit formed by R3 and C10. The resulting interference-free signal is transmitted to the subsequent AD conversion processing unit through socket J4 for signal conversion processing.

[0025] refer to Figure 2The negative-pressure air output by the air compressor enters the pressure sensor through the air input port. The pressure sensor detects the gas pressure and, after passing through the sensor's internal pressure-sensitive components and circuitry, outputs two signals at pins 3 and 5 of pressure sensor XM2, respectively. Signal XM2_5 enters the voltage follower U2C via the non-inverting terminal. After passing through resistor R25, the output signal enters the inverting input of op amp U2B. This signal, combined with signal XM2_3, which is input via the non-inverting terminal of op amp U2B, forms a differential operational amplifier circuit. Phase compensation circuit C13 then performs phase compensation on the input signals, eliminating common-mode interference and compensating for phase differences. After passing through the follower and differential amplifier, the amplified signals XM2_5 and XM2_3 enter the inverting operational amplifier circuit U2A via R27, achieving a 15x gain. After phase compensation via C14, the amplified signals are output at U2A_1. The voltage sampled by rheostat R32 passes through resistor R33 and voltage follower U2D, and is input to the lower end of rheostat R41. By adjusting rheostat R32, the amplitude of the amplified output signal can be varied, thereby widening the amplitude range of the signal for subsequent processing. The amplified signal passes through sampling rheostat R41, where the amplitude is selected to be suitable for subsequent processing. The signal then flows through current-limiting resistor R39, the filter network formed by R40 and C12, and the low-pass filter circuit formed by R43 and C11. The resulting interference-free signal is transmitted to the subsequent AD conversion processing unit through socket J4 for signal conversion processing.

[0026] The above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application. Other embodiments whose principles and basic structures are the same or similar to those of the present application are within the scope of protection of the present application.

Claims

1. A pressure detection signal processing circuit for a blood analyzer, characterized in that: It includes a positive voltage input terminal XM1, pin 2 of the positive voltage input terminal XM1 inputs a first voltage, pin 3 is connected to the positive phase terminal of the voltage follower U1-C, the inverting terminal of the voltage follower U1-C is connected to the second voltage through a resistor R4, a resistor R5 is connected between the inverting terminal and the output terminal of the voltage follower U1-C, and the output terminal is further connected to the inverting terminal of the operational amplifier U1-B through a resistor R6, the positive phase terminal of the operational amplifier U1-B is connected to pin 5 of the positive voltage input terminal XM1, the output terminal of the operational amplifier U1-B is connected to the inverting terminal of the operational amplifier U1-A through a resistor R8, and the output terminal of the operational amplifier U1-A is connected to a variable resistor R20; The non-inverting terminal of the operational amplifier U1-A is connected to the variable resistor R20 through a resistor R18, and is also connected to the variable resistor R12 through a resistor R15. The second voltage is connected to the variable resistor R12 through a resistor R10, and the other end of the variable resistor R12 is grounded through a resistor R16. The second voltage is connected to the variable resistor R13 through a resistor R11, and the variable resistor R13 is grounded through a resistor R17. The variable resistor R13 is also connected to the non-inverting terminal of the operational amplifier U1-D through a resistor R14. The inverting terminal of the operational amplifier U1-D is connected to its output terminal through a resistor R19, and the output terminal is connected to the variable resistor R20. The variable resistor R20 outputs through pin 1 of the output terminal J2; It also includes a negative voltage input terminal XM2, pin 2 of the negative voltage input terminal XM2 also inputs the first voltage, its pin 5 is connected to the positive phase terminal of the voltage follower U2-C, the inverting terminal of the voltage follower U2-C is connected to the second voltage through a resistor R23, its output terminal is connected to the inverting terminal of the operational amplifier U2-B through a resistor R25, the positive phase terminal of the operational amplifier U2-B is connected to pin 3 of the negative voltage input terminal XM2, the output terminal of the operational amplifier U2-B is connected to the inverting terminal of the operational amplifier U2-A through a resistor R27, the output terminal of the operational amplifier U2-A is connected to a variable resistor R41, and the positive phase terminal of the operational amplifier U2-A is connected to the negative phase terminal of the operational amplifier U2-A through a resistor R37. It is connected to the variable resistor R41 and is also connected to the variable resistor R31 through the resistor R34. The second voltage is grounded through the resistor R29, the variable resistor R31 and the resistor R35 in sequence, and is also grounded through the resistor R30, the variable resistor R32 and the resistor R36. The variable resistor R32 is connected to the positive phase terminal of the operational amplifier U2-D through the resistor R33. The inverting terminal of the operational amplifier U2-D is connected to its output terminal through the resistor R38, and is connected to the other end of the variable resistor R41. The variable resistor R41 is output through pin 3 of the output terminal J2. A resistor R24 ​​is connected between the inverting terminal and the output terminal of the voltage follower U2-C.

2. The air pressure detection signal processing circuit for a blood analyzer according to claim 1, characterized in that: A capacitor C7 and a resistor R7 are provided between the inverting terminal and the output terminal of the operational amplifier U1-B, and a capacitor C13 and a resistor R26 are provided between the inverting terminal and the output terminal of the operational amplifier U2-B.

3. The air pressure detection signal processing circuit for a blood analyzer according to claim 2, characterized in that: The variable resistor R20 is connected to the output terminal J2 via the resistor R21 and the resistor R3. The resistor R21 is grounded via the resistor R22 and also grounded via the capacitor C9. The resistor R3 is grounded via the capacitor C10. The variable resistor R41 is connected to the output terminal J2 via a resistor R39 and a resistor R43 . The resistor R39 is grounded via a resistor R40 and also grounded via a capacitor C12 . The resistor R43 is grounded via a capacitor C11 .

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