Impedance given circuit

Abstract

The present invention discloses an impedance setting circuit comprising: a control circuit, which is used to continuously output different first voltage signals and different second voltage signals to a heartbeat interference circuit and a signal conversion circuit respectively; a heartbeat interference circuit, which is used to convert the first voltage signal into a sinusoidal voltage signal and output it to the signal conversion circuit; a signal conversion circuit, which is used to convert the sinusoidal voltage signal into a first current signal, convert the second voltage signal into a second current signal, and transmit it to an impedance generating circuit; and an impedance generating circuit, which generates a first impedance and a second impedance according to the first current signal and the second current signal respectively. The present application introduces a heartbeat interference circuit, which is closer to the actual situation of the human body when breathing, so that the first impedance and the second impedance are also closer to the impedance generated by the human body during detection. The present application provides convenience for the factory detection of the monitoring device, and can output an impedance close to the human body to simulate the breathing state of the human body.

Description

Technical Field

[0001] The present invention relates to the technical field of impedance setting, and in particular to an impedance setting circuit. Background Art

[0002] With the development of the medical industry, life support medical equipment has become more and more diverse, especially monitoring devices for measuring the human respiratory system, such as monitors. In the prior art, in the circuit for calibrating the monitor that measures human breathing through the chest impedance method, heartbeat interference is not considered, resulting in the impedance output to the monitor being significantly different from the actual situation, and it is impossible to output an impedance close to the actual human body to the monitor. Summary of the invention

[0003] Based on this, it is necessary to propose an impedance given circuit to address the above problems.

[0004] An impedance given circuit, comprising:

[0005] A control circuit, connected to the heartbeat interference circuit and the signal conversion circuit, for continuously outputting different first voltage signals and different second voltage signals to the heartbeat interference circuit and the signal conversion circuit respectively;

[0006] The heartbeat interference circuit is connected to the signal conversion circuit, and is used to convert the received first voltage signal into a sinusoidal voltage signal, and output it to the signal conversion circuit;

[0007] The signal conversion circuit is connected to the impedance generating circuit, and is used to convert the received sinusoidal wave voltage signal into a first current signal, and transmit it to the impedance generating circuit; convert the received second voltage signal into a second current signal, and transmit it to the impedance generating circuit; and

[0008] The impedance generating circuit is connected to the first current signal and the second current signal output by the signal conversion circuit, and generates a first impedance and a second impedance according to the first current signal and the second current signal respectively. The monitoring device applies a detection voltage to the impedance generating circuit, and the monitoring device obtains a divided voltage after the detection voltage is divided by the first impedance and the second impedance.

[0009] In one embodiment, the impedance setting circuit further includes:

[0010] A skin impedance interference circuit is connected to the control circuit, receives a control signal sent by the control circuit, and adjusts and outputs a third impedance according to the control signal; the monitoring device applies the detection voltage to the first impedance, the second impedance and the third impedance, and obtains a divided voltage after the detection voltage is divided by the first impedance, the second impedance and the third impedance.

[0011] In one embodiment, the heartbeat interference circuit includes:

[0012] A first waveform conversion circuit, connected to the control circuit, for converting the received first voltage signal into a square wave voltage signal, and transmitting the square wave voltage signal to a second waveform conversion circuit;

[0013] The second waveform conversion circuit is connected to the signal conversion circuit, receives the square wave voltage signal, converts the square wave voltage signal into a sine wave voltage signal, and outputs the sine wave voltage signal to the signal conversion circuit.

[0014] In one embodiment, the first waveform conversion circuit includes: a first operational amplifier, a second operational amplifier, a third operational amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor and a second capacitor;

[0015] The non-inverting input terminal of the first operational amplifier is grounded, and the inverting input terminal is connected to the first voltage signal; the two ends of the first resistor are respectively connected to the inverting input terminal and the output terminal of the first operational amplifier; one end of the second resistor is connected to the output terminal of the first operational amplifier, and the other end is connected to the inverting input terminal of the second operational amplifier; the two ends of the third resistor are respectively connected to the inverting input terminal and the output terminal of the second operational amplifier; the first capacitor is connected in parallel with the first resistor; the second capacitor is connected in parallel with the third resistor; the non-inverting input terminal of the second operational amplifier is grounded; one end of the fourth resistor is connected to the output terminal of the second operational amplifier, and the other end is connected to the inverting input terminal of the third operational amplifier; the two ends of the fifth resistor are respectively connected to the non-inverting input terminal and the output terminal of the third operational amplifier; the output terminal of the third operational amplifier outputs the square wave voltage signal.

[0016] In one embodiment, the second waveform conversion circuit includes: a fourth operational amplifier, a fifth operational amplifier, a sixth operational amplifier, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a third capacitor, a fourth capacitor, a fifth capacitor, and a sixth capacitor;

[0017] The non-inverting input terminal of the fourth operational amplifier is connected to the square wave voltage signal, and the inverting input terminal is connected to the output terminal; one end of the sixth resistor is connected to the output terminal of the fourth operational amplifier, and the other end is connected to one end of the seventh resistor, and the other end of the seventh resistor is connected to the inverting input terminal of the fifth operational amplifier; the two ends of the eighth resistor are respectively connected to the inverting input terminal and the output terminal of the fifth operational amplifier; the non-inverting input terminal of the fifth operational amplifier is grounded, the output terminal of the fifth operational amplifier is connected to one end of the ninth resistor, the other end of the ninth resistor is connected to one end of the tenth resistor, the other end of the tenth resistor is connected to one end of the fifth capacitor, and the fifth capacitor is connected to the inverting input terminal and the output terminal of the fifth operational amplifier. The other end of the capacitor is connected to the inverting input terminal of the sixth operational amplifier; the two ends of the eleventh resistor are respectively connected to the inverting input terminal and the output terminal of the sixth operational amplifier; one end of the twelfth resistor is connected to the connection point of the tenth resistor and the fifth capacitor, and the other end is grounded; one end of the thirteenth resistor is connected to the non-inverting input terminal of the sixth operational amplifier, and the other end is grounded; one end of the fourth capacitor is connected to the connection point of the ninth resistor and the tenth resistor, and the other end is grounded; the third capacitor is connected to the eighth resistor in parallel; one end of the sixth capacitor is connected to the connection point of the tenth resistor and the fifth capacitor; the output terminal of the sixth operational amplifier outputs the sinusoidal wave voltage signal.

[0018] In one embodiment, the control signal includes a first control signal and a second control signal;

[0019] The skin impedance interference circuit comprises: an analog switch, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor and an adjustable resistor;

[0020] The signal input end of the analog switch is connected to the first control signal sent by the control circuit, and the multiple output ends are respectively connected to one end of the seventh capacitor, the eighth capacitor, the ninth capacitor and the tenth capacitor, and the other ends of the seventh capacitor, the eighth capacitor, the ninth capacitor and the tenth capacitor are all connected to the output end of the impedance generating circuit, and the analog switch adjusts the capacitance of the seventh capacitor, the eighth capacitor, the ninth capacitor and the tenth capacitor according to the first control signal;

[0021] The signal input end of the adjustable resistor is connected to the second control signal sent by the control circuit, the first signal output end of the adjustable resistor is connected to the common end of the analog switch, and the second output end is connected to the output end of the impedance generating circuit.

[0022] In one embodiment, the signal conversion circuit includes:

[0023] A first constant current source circuit, used for converting the sinusoidal wave voltage signal into the first current signal;

[0024] A second constant current source circuit is used for converting the second voltage signal into the second current signal.

[0025] In one embodiment, the first constant current source circuit comprises: a seventh operational amplifier, an eighth operational amplifier, a fourteenth resistor, a fifteenth resistor and a sixteenth resistor;

[0026] The non-inverting input terminal of the seventh operational amplifier is connected to the sinusoidal wave voltage signal, and the inverting input terminal and the non-inverting input terminal of the seventh operational amplifier are both connected to the non-inverting input terminal of the eighth operational amplifier; the inverting input terminal and the output terminal of the eighth operational amplifier are both connected to the non-inverting input terminal of the seventh operational amplifier; the fourteenth resistor is connected between the output terminal of the seventh operational amplifier and the non-inverting input terminal of the eighth operational amplifier; the fifteenth resistor is connected between the inverting input terminal and the output terminal of the seventh operational amplifier; the sixteenth resistor is connected between the output terminal of the eighth operational amplifier and the non-inverting input terminal of the seventh operational amplifier.

[0027] In one embodiment, the second constant current source circuit includes: a ninth operational amplifier, a tenth operational amplifier, a seventeenth resistor, an eighteenth resistor and a nineteenth resistor;

[0028] The non-inverting input terminal of the ninth operational amplifier is connected to the second voltage signal, and the inverting input terminal and the non-inverting input terminal of the ninth operational amplifier are both connected to the non-inverting input terminal of the tenth operational amplifier; the inverting input terminal and the output terminal of the tenth operational amplifier are both connected to the non-inverting input terminal of the ninth operational amplifier; the seventeenth resistor is connected between the output terminal of the ninth operational amplifier and the non-inverting input terminal of the tenth operational amplifier; the eighteenth resistor is connected between the inverting input terminal and the output terminal of the ninth operational amplifier; the nineteenth resistor is connected between the output terminal of the tenth operational amplifier and the non-inverting input terminal of the ninth operational amplifier.

[0029] In one embodiment, the impedance generating circuit includes: a first light emitting diode, a second light emitting diode, a first phototransistor and a second phototransistor;

[0030] The anode of the first light emitting diode is connected to the second current signal, and the cathode is grounded;

[0031] The anode of the second light emitting diode is connected to the above, and the cathode is grounded;

[0032] The collector of the first phototransistor is connected to the monitoring device to receive the detection voltage applied by the monitoring device; the emitter of the first phototransistor is connected to the collector of the second phototransistor, and the emitter of the second phototransistor is grounded;

[0033] The first phototransistor receives light emitted by the first light-emitting diode and changes its own impedance according to the intensity of the light; the second phototransistor receives light emitted by the second light-emitting diode and changes its own impedance according to the intensity of the light.

[0034] Implementing the embodiments of the present invention will have the following beneficial effects:

[0035] When the monitoring device is factory tested, the present application simulates the human body, and the control circuit continuously sends different first voltage signals and second voltage signals to the heartbeat interference circuit and the signal conversion circuit respectively; the heartbeat interference circuit converts the first voltage signal into a sinusoidal voltage signal and outputs it to the signal conversion circuit, the signal conversion circuit converts the sinusoidal voltage signal into a first current signal, and converts the second voltage signal into a second current signal; the impedance generation circuit generates a first impedance and a second impedance according to the first current signal and the second current signal respectively to simulate the impedance generated by the human body during each breath, and the monitoring device then applies a detection voltage to the first impedance and the second impedance, and detects the divided voltage divided into the first impedance and the second impedance at a certain time interval and forms a breathing curve, and compares it with the preset breathing curve to judge the detection accuracy of the monitoring device. The present application introduces a heartbeat interference circuit, which is closer to the actual situation of the human body when breathing, so that the first impedance and the second impedance are also closer to the impedance generated by the human body during detection. The present application provides convenience for the factory testing of the monitoring device, and can output an impedance close to the human body to simulate the breathing state of the human body. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] in:

[0038] Figure 1 is a structural block diagram of an impedance given circuit in an embodiment;

[0039] Figure 2 is a structural block diagram of an impedance given circuit in another embodiment;

[0040] Figure 3 is a circuit diagram of a control circuit in one embodiment;

[0041] Figure 4 A circuit diagram of a heartbeat interference circuit in one embodiment;

[0042] Figure 5 A circuit diagram of a heartbeat interference circuit of another channel in one embodiment;

[0043] Figure 6 is a circuit diagram of a first constant current source circuit in an embodiment;

[0044] Figure 7 is a circuit diagram of a second constant current source circuit in one embodiment;

[0045] Figure 8 is a circuit diagram of a first constant current source circuit of another channel in one embodiment;

[0046] Fig. 9 is a circuit diagram of a second constant current source circuit of another channel in one embodiment;

[0047] Fig.10 1 is a circuit diagram of an impedance generating circuit and a skin impedance interference circuit in one embodiment and an impedance generating circuit and a skin impedance interference circuit in another channel. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] The present application is used to test a monitoring device that has not been put into use, that is, a monitor for detecting human breathing; when a human body breathes, the impedance of a specific part of its body will change with the change of breathing, that is, the detected part is equivalent to a resistor with a certain impedance; the monitor in the prior art is connected to different parts of the human body through three wires, one of which is a common end, for example, wire A is connected to the left arm, wire B is connected to the left abdomen, and wire C is connected to the right arm; then the monitor can apply voltage to the impedance between the left arm and the left abdomen and the impedance between the right arm and the left abdomen. Due to the presence of other media, the applied voltage may be divided. Then the monitor directly collects the divided voltage between the left arm and the left abdomen and the divided voltage between the right arm and the left abdomen, forms a breathing curve based on the obtained divided voltage, and compares it with the preset breathing curve to determine the accuracy of the monitor. Therefore, the main purpose of this application is to introduce a heartbeat interference circuit, which is closer to the actual situation of the human body when breathing, so that the first impedance and the second impedance are also closer to the impedance generated by the human body during detection. This application provides convenience for factory inspection of monitoring devices and can output impedance close to the human body to simulate the breathing state of the human body.

[0050] Figure 1 FIG. 1 is a structural block diagram of an impedance setting circuit in an embodiment. Figure 1 , the present application provides an impedance given circuit, comprising:

[0051] The control circuit 10 is connected to the heartbeat interference circuit 20 and the signal conversion circuit 30, and is used to continuously output different first voltage signals ECG_WAVE1 and different second voltage signals V_WAVE1 to the heartbeat interference circuit 20 and the signal conversion circuit 30 respectively;

[0052] The heartbeat interference circuit 20 is connected to the signal conversion circuit 30, and is used to convert the received first voltage signal ECG_WAVE1 into a sinusoidal wave voltage signal ECG_R_WAVE1, and output it to the signal conversion circuit 30;

[0053] The signal conversion circuit 30 is connected to the impedance generation circuit 40, and is used to convert the received sinusoidal wave voltage signal ECG_R_WAVE1 into a first current signal Constant_Current_Out_B, and transmit it to the impedance generation circuit 40; convert the received second voltage signal V_WAVE1 into a second current signal Constant_Current_Out_A, and transmit it to the impedance generation circuit 40; and

[0054] The impedance generating circuit 40 is connected to the first current signal Constant_Current_Out_B and the second current signal Constant_Current_Out_A output by the signal conversion circuit 30, and generates a first impedance and a second impedance according to the first current signal Constant_Current_Out_B and the second current signal Constant_Current_Out_A, respectively. The monitoring device 50 applies a detection voltage to the impedance generating circuit 40, and the monitoring device 50 obtains a divided voltage after the detection voltage is divided by the first impedance and the second impedance.

[0055] Specifically, the control circuit 10 outputs a first voltage signal simulating a heartbeat to the heartbeat interference circuit 20, and the heartbeat interference circuit 20 converts the first voltage signal into a sinusoidal wave voltage signal ECG_R_WAVE1 and outputs it to the signal conversion circuit 30; the signal conversion circuit 30 converts the sinusoidal wave voltage signal ECG_R_WAVE1 into a first current signal Constant_Current_Out_B, and the impedance generating circuit 40 accesses the first current signal Constant_Current_Out_B and generates a first impedance based on it; different digital signals, such as "00", "01", "10" and "11", are written to the control circuit 10 at preset time intervals through a host computer or a touch screen. The control circuit 10 determines the corresponding second voltage signal according to each digital signal, where the second voltage signal is used to simulate human breathing, and sends the second voltage signal to the signal conversion circuit 30 at a preset time, and then converts the second voltage signal into a second current signal through the signal conversion module 20 to apply it to the impedance generating circuit 40. The impedance generating circuit 40 generates a second impedance according to the second current signal. The monitoring device 50 applies a detection voltage to the first impedance and the second impedance of the impedance generating circuit 40, and obtains the divided voltage after the first impedance and the second impedance divide the detection voltage. The monitoring device 50 generates a breathing curve according to the divided voltage, and compares it with the preset breathing curve to determine the accuracy of the monitor.

[0056] In one embodiment, Figure 2 As shown, the impedance given circuit also includes:

[0057] The skin impedance interference circuit 60 is connected to the control circuit 10, receives the control signal sent by the control circuit 10, and adjusts and outputs the third impedance according to the control signal; the monitoring device 50 applies the detection voltage to the first impedance, the second impedance and the third impedance, and obtains the divided voltage after the first impedance, the second impedance and the third impedance divide the detection voltage.

[0058] Wherein, the control signal includes a first control signal and a second control signal;

[0059] The skin impedance interference circuit 60 includes: an analog switch U28, a seventh capacitor C399, an eighth capacitor C400, a ninth capacitor C401, a tenth capacitor C402 and an adjustable resistor U27;

[0060] The signal input end of the analog switch U28 is connected to the first control signal sent by the control circuit 10, and the multiple output ends are respectively connected to one end of the seventh capacitor C399, the eighth capacitor C400, the ninth capacitor C401 and the tenth capacitor C402, and the other ends of the seventh capacitor C399, the eighth capacitor C400, the ninth capacitor C401 and the tenth capacitor C402 are all connected to the output end of the impedance generating circuit 40, and the analog switch U28 adjusts the capacitance of the seventh capacitor C399, the eighth capacitor C400, the ninth capacitor C401 and the tenth capacitor C402 according to the first control signal;

[0061] The signal input end of the adjustable resistor U27 is connected to the second control signal sent by the control circuit 10 , the first signal output end of the adjustable resistor U27 is connected to the common end of the analog switch U28 , and the second output end is connected to the output end of the impedance generating circuit 40 .

[0062] In one embodiment, the heartbeat interference circuit 20 includes:

[0063] The first waveform conversion circuit 21 is connected to the control circuit 10, such as Figure 3 , which is a circuit diagram of a control circuit, used to convert the received first voltage signal ECG_WAVE1 into a square wave voltage signal, and transmit it to the second waveform conversion circuit 22;

[0064] The second waveform conversion circuit 22 is connected to the signal conversion circuit 30 , receives the square wave voltage signal, converts the square wave voltage signal into a sinusoidal wave voltage signal ECG_R_WAVE1 , and outputs the converted signal to the signal conversion circuit 30 .

[0065] Among them, Figure 4 As shown, the first waveform conversion circuit 21 includes: a first operational amplifier U41A, a second operational amplifier U41B, a third operational amplifier U39A, a first resistor R139, a second resistor R138, a third resistor R137, a fourth resistor R136, a fifth resistor R130, a first capacitor C175 and a second capacitor C177;

[0066] The non-inverting input terminal of the first operational amplifier U41A is grounded, and the inverting input terminal is connected to the first voltage signal ECG_WAVE1; the two ends of the first resistor R139 are respectively connected to the inverting input terminal and the output terminal of the first operational amplifier U41A; one end of the second resistor R138 is connected to the output terminal of the first operational amplifier U41A, and the other end is connected to the inverting input terminal of the second operational amplifier U41B; the two ends of the third resistor R137 are respectively connected to the inverting input terminal and the output terminal of the second operational amplifier U41B; the first capacitor C17 5 is connected in parallel with the first resistor R139; the second capacitor C177 is connected in parallel with the third resistor R137; the non-inverting input terminal of the second operational amplifier U41B is grounded; one end of the fourth resistor R136 is connected to the output terminal of the second operational amplifier U41B, and the other end is connected to the inverting input terminal of the third operational amplifier U39A; both ends of the fifth resistor R130 are respectively connected to the non-inverting input terminal and output terminal of the third operational amplifier U39A; the output terminal of the third operational amplifier U39A outputs the square wave voltage signal ECG_RFLAG1.

[0067] The second waveform conversion circuit 22 includes: a fourth operational amplifier U42D, a fifth operational amplifier U42C, a sixth operational amplifier U42B, a sixth resistor R94, a seventh resistor R95, an eighth resistor R89, a ninth resistor R96, a tenth resistor R97, an eleventh resistor R90, a twelfth resistor R101, a thirteenth resistor R102, a third capacitor C135, a fourth capacitor C143, a fifth capacitor C141, and a sixth capacitor C136;

[0068] The non-inverting input terminal of the fourth operational amplifier U42D is connected to the square wave voltage signal ECG_RFLAG1, and the inverting input terminal is connected to the output terminal; one end of the sixth resistor R94 is connected to the output terminal of the fourth operational amplifier U42D, and the other end is connected to one end of the seventh resistor R95, and the other end of the seventh resistor R95 is connected to the inverting input terminal of the fifth operational amplifier U42C; the two ends of the eighth resistor R89 ​​are respectively connected to the inverting input terminal and the output terminal of the fifth operational amplifier U42C; the non-inverting input terminal of the fifth operational amplifier U42C is grounded, and the output terminal of the fifth operational amplifier U42C is connected to one end of the ninth resistor R96, and the other end of the ninth resistor R96 is connected to one end of the tenth resistor R97, and the other end of the tenth resistor R97 is connected to one end of the fifth capacitor C141, and the other end of the fifth capacitor C141 is connected to one end of the fifth capacitor C141. One end is connected to the inverting input terminal of the sixth operational amplifier U42B; both ends of the eleventh resistor R90 are respectively connected to the inverting input terminal and the output terminal of the sixth operational amplifier U42B; one end of the twelfth resistor R101 is connected to the connection point of the tenth resistor R97 and the fifth capacitor C141, and the other end is grounded; one end of the thirteenth resistor R102 is connected to the non-inverting input terminal of the sixth operational amplifier U42B, and the other end is grounded; one end of the fourth capacitor C143 is connected to the connection point of the ninth resistor R96 and the tenth resistor R97, and the other end is grounded; the third capacitor C135 is connected in parallel with the eighth resistor R89; one end of the sixth capacitor C136 is connected to the connection point of the tenth resistor R97 and the fifth capacitor C141; the output end of the sixth operational amplifier U42B outputs the sinusoidal wave voltage signal ECG_R_WAVE1.

[0069] In one embodiment, the signal conversion circuit 30 includes:

[0070] A first constant current source circuit 301, used for converting the sinusoidal wave voltage signal ECG_R_WAVE1 into the first current signal Constant_Current_Out_B;

[0071] The second constant current source circuit 302 is used for converting the second voltage signal V_WAVE1 into the second current signal Constant_Current_Out_A.

[0072] Among them, Figure 6 As shown, the first constant current source circuit 301 includes: a seventh operational amplifier U33C, an eighth operational amplifier U34B, a fourteenth resistor R329, a fifteenth resistor R330 and a sixteenth resistor R331;

[0073] The non-inverting input terminal of the seventh operational amplifier U33C is connected to the sinusoidal wave voltage signal ECG_R_WAVE1, and the inverting input terminal and the non-inverting input terminal of the seventh operational amplifier U33C are both connected to the non-inverting input terminal of the eighth operational amplifier U34B; the inverting input terminal and the output terminal of the eighth operational amplifier U34B are both connected to the non-inverting input terminal of the seventh operational amplifier U33C; the fourteenth resistor R329 is connected between the output terminal of the seventh operational amplifier U33C and the non-inverting input terminal of the eighth operational amplifier U34B; the fifteenth resistor R330 is connected between the inverting input terminal and the output terminal of the seventh operational amplifier U33C; the sixteenth resistor R331 is connected to the output terminal of the eighth operational amplifier U34B and the non-inverting input terminal of the seventh operational amplifier U33C.

[0074] like Figure 7 As shown, the second constant current source circuit 302 includes: a ninth operational amplifier U17A, a tenth operational amplifier U17B, a seventeenth resistor R112, an eighteenth resistor R118 and a nineteenth resistor R119;

[0075] The non-inverting input terminal of the ninth operational amplifier U17A is connected to the second voltage signal V_WAVE1, and the inverting input terminal and the non-inverting input terminal of the ninth operational amplifier U17A are both connected to the non-inverting input terminal of the tenth operational amplifier U17B; the inverting input terminal and the output terminal of the tenth operational amplifier U17B are both connected to the non-inverting input terminal of the ninth operational amplifier U17A; the seventeenth resistor R112 is connected between the output terminal of the ninth operational amplifier U17A and the non-inverting input terminal of the tenth operational amplifier U17B; the eighteenth resistor R118 is connected between the inverting input terminal and the output terminal of the ninth operational amplifier U17A; the nineteenth resistor R119 is connected between the output terminal of the tenth operational amplifier U17B and the non-inverting input terminal of the ninth operational amplifier U17A.

[0076] In one embodiment, the impedance generating circuit 40 includes: a first light emitting diode D20, a second light emitting diode D25, a first phototransistor Q1 and a second phototransistor Q5;

[0077] The anode of the first light emitting diode D20 is connected to the second current signal Constant_Current_Out_A, and the cathode is grounded;

[0078] The anode of the second light emitting diode D25 is connected to the Constant_Current_Out_B, and the cathode is grounded;

[0079] The collector of the first phototransistor Q1 is connected to the monitoring device 50 to receive the detection voltage applied thereto; the emitter of the first phototransistor Q1 is connected to the collector of the second phototransistor Q5, and the emitter of the second phototransistor Q5 is grounded;

[0080] The first phototransistor Q1 receives light emitted by the first light-emitting diode D20 and changes its own impedance according to the intensity of the light; the second phototransistor Q5 receives light emitted by the second light-emitting diode D25 and changes its own impedance according to the intensity of the light.

[0081] The specific working principle is as follows: Since the monitoring device 50 can collect the impedance of two parts of the human body, the impedance can be given through two channels in this application.

[0082] The control circuit 10 sends a first voltage signal to the first waveform conversion circuit 21, the first waveform conversion circuit 21 converts the first voltage signal into a square wave voltage signal and transmits it to the second waveform conversion circuit 22, the second waveform conversion circuit 22 converts the square wave voltage signal into a sine wave voltage signal ECG_R_WAVE1 and outputs it to the first constant current source circuit 301, the first constant current source circuit 301 converts the sine wave voltage signal ECG_R_WAVE1 into a first current signal Constant_Current_Out_B, and applies it to the second light emitting diode D2 5 emits light, the second phototransistor Q5 receives the light emitted by the second light-emitting diode D25, thereby changing the size of its own impedance, and its impedance changes to the first impedance; the control circuit 10 sends a second voltage signal to the second constant current source circuit 302; the second constant current source circuit 302 converts the second voltage signal into a second current signal, and applies it to the first light-emitting diode D20 for emitting light, the first phototransistor Q1 receives the light emitted by the first light-emitting diode D20, thereby changing the size of its own impedance, and its impedance changes to the second impedance; at the same time, in order to better simulate the human body, the skin is also added The skin impedance interference circuit 60 includes: an analog switch U28, a seventh capacitor C399, an eighth capacitor C400, a ninth capacitor C401, a tenth capacitor C402 and an adjustable resistor U27; the analog switch U28, the seventh capacitor C399, the eighth capacitor C400, the ninth capacitor C401, and the tenth capacitor C402 constitute an adjustable capacitor, and the analog switch U28 is controlled by the control circuit 10 to adjust the size of the seventh capacitor C399, the eighth capacitor C400, the ninth capacitor C401, and the tenth capacitor C402 respectively to simulate the capacitance size of human skin; Then, the control circuit 10 controls the adjustable rheostat U27 to change its own impedance to simulate the third impedance of the human skin; in summary, the first impedance, the second impedance and the third impedance are combined to complete the output of the simulated impedance when the human body breathes, and the monitoring device 50 applies the detection voltage to the first impedance, the second impedance and the third impedance, and obtains the divided voltage after the first impedance, the second impedance and the third impedance divide the detection voltage, and forms a breathing curve according to the obtained divided voltage, and compares it with the preset breathing curve to judge the accuracy of the monitor. Then, the main purpose of this application is to introduce a heartbeat interference circuit, which is closer to the actual situation of the human body when breathing, so that the first impedance and the second impedance are also closer to the impedance generated by the human body during detection. This application provides convenience for the factory detection of the monitoring device, and can output an impedance close to the human body to simulate the breathing state of the human body.

[0083] Among them, Figure 5 Used to output the sinusoidal voltage signal ECG_R_WAVE2 of another channel, such as Figure 8Used to convert the sinusoidal wave voltage signal ECG_R_WAVE2 of another channel into a third current signal; Fig. 9 To convert the voltage signal output by the control circuit of another channel into a fourth current signal, the third current signal and the fourth current signal are applied to Fig.10 The third light-emitting diode D27 and the fourth light-emitting diode D26 in the control circuit 10 respectively adjust the sizes of the twentieth capacitor C409, the twenty-first capacitor C411, the twenty-second capacitor C410, and the twenty-third capacitor C412 to simulate the capacitance size of another part of the human skin; the control circuit 10 controls the adjustable resistor U31 to change its own impedance size to simulate the sixth impedance of the human skin, and the monitoring device applies the detection voltage to the fourth impedance, the fifth impedance, and the sixth impedance, and obtains the divided voltage after the fourth impedance, the fifth impedance, and the sixth impedance divide the detection voltage (the subsequent processing is the same as the processing of the above-mentioned channel, and will not be repeated).

[0084] The present application simulates a human body, and the control circuit continuously sends different first voltage signals and second voltage signals to a heartbeat interference circuit and a signal conversion circuit respectively; the heartbeat interference circuit converts the first voltage signal into a sinusoidal voltage signal and outputs it to the signal conversion circuit, the signal conversion circuit converts the sinusoidal voltage signal into a first current signal, and converts the second voltage signal into a second current signal; the impedance generation circuit generates a first impedance and a second impedance according to the first current signal and the second current signal respectively to simulate the impedance generated by the human body during each breath, the monitoring device then applies a detection voltage to the first impedance and the second impedance, and detects the divided voltage on the first impedance and the second impedance at a certain time interval and forms a breathing curve, and compares it with the preset breathing curve to judge the detection accuracy of the monitoring device. The present application introduces a heartbeat interference circuit, which is closer to the actual situation of the human body when breathing, so that the first impedance and the second impedance are also closer to the impedance generated by the human body during detection. The present application provides convenience for the factory detection of the monitoring device, and can output an impedance close to the human body to simulate the breathing state of the human body.

[0085] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. An impedance setting circuit, characterized in that: include: A control circuit, connected to the heartbeat interference circuit and the signal conversion circuit, for continuously outputting different first voltage signals and different second voltage signals to the heartbeat interference circuit and the signal conversion circuit respectively; The heartbeat interference circuit is connected to the signal conversion circuit, and is used to convert the received first voltage signal into a sinusoidal voltage signal, and output it to the signal conversion circuit; The signal conversion circuit is connected to the impedance generation circuit and is used to convert the received sinusoidal voltage signal into a first current signal and transmit it to the impedance generation circuit; converting the received second voltage signal into a second current signal, and transmitting the second current signal to the impedance generating circuit; and The impedance generating circuit is connected to the first current signal and the second current signal output by the signal conversion circuit, and generates a first impedance and a second impedance according to the first current signal and the second current signal respectively. The monitoring device applies a detection voltage to the impedance generating circuit, and the monitoring device obtains a divided voltage after the detection voltage is divided by the first impedance and the second impedance.

2. The impedance setting circuit according to claim 1, characterized in that: Also includes: A skin impedance interference circuit is connected to the control circuit, receives a control signal sent by the control circuit, and adjusts and outputs a third impedance according to the control signal; The monitoring device applies the detection voltage to the first impedance, the second impedance, and the third impedance, and obtains a divided voltage after the detection voltage is divided by the first impedance, the second impedance, and the third impedance.

3. The impedance setting circuit according to claim 1, characterized in that: The heartbeat interference circuit comprises: A first waveform conversion circuit, connected to the control circuit, for converting the received first voltage signal into a square wave voltage signal, and transmitting the square wave voltage signal to a second waveform conversion circuit; The second waveform conversion circuit is connected to the signal conversion circuit, receives the square wave voltage signal, converts the square wave voltage signal into a sine wave voltage signal, and outputs the sine wave voltage signal to the signal conversion circuit.

4. The impedance setting circuit according to claim 3, characterized in that: The first waveform conversion circuit includes: a first operational amplifier, a second operational amplifier, a third operational amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor and a second capacitor; The non-inverting input terminal of the first operational amplifier is grounded, and the inverting input terminal is connected to the first voltage signal; the two ends of the first resistor are respectively connected to the inverting input terminal and the output terminal of the first operational amplifier; one end of the second resistor is connected to the output terminal of the first operational amplifier, and the other end is connected to the inverting input terminal of the second operational amplifier; the two ends of the third resistor are respectively connected to the inverting input terminal and the output terminal of the second operational amplifier; the first capacitor is connected in parallel with the first resistor; the second capacitor is connected in parallel with the third resistor; the non-inverting input terminal of the second operational amplifier is grounded; one end of the fourth resistor is connected to the output terminal of the second operational amplifier, and the other end is connected to the inverting input terminal of the third operational amplifier; the two ends of the fifth resistor are respectively connected to the non-inverting input terminal and the output terminal of the third operational amplifier; the output terminal of the third operational amplifier outputs the square wave voltage signal.

5. The impedance setting circuit according to claim 3, characterized in that: The second waveform conversion circuit includes: a fourth operational amplifier, a fifth operational amplifier, a sixth operational amplifier, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a third capacitor, a fourth capacitor, a fifth capacitor, and a sixth capacitor; The non-inverting input terminal of the fourth operational amplifier is connected to the square wave voltage signal, and the inverting input terminal is connected to the output terminal; one end of the sixth resistor is connected to the output terminal of the fourth operational amplifier, and the other end is connected to one end of the seventh resistor, and the other end of the seventh resistor is connected to the inverting input terminal of the fifth operational amplifier; the two ends of the eighth resistor are respectively connected to the inverting input terminal and the output terminal of the fifth operational amplifier; the non-inverting input terminal of the fifth operational amplifier is grounded, the output terminal of the fifth operational amplifier is connected to one end of the ninth resistor, the other end of the ninth resistor is connected to one end of the tenth resistor, the other end of the tenth resistor is connected to one end of the fifth capacitor, and the fifth capacitor is connected to the inverting input terminal and the output terminal of the fifth operational amplifier. The other end of the capacitor is connected to the inverting input terminal of the sixth operational amplifier; the two ends of the eleventh resistor are respectively connected to the inverting input terminal and the output terminal of the sixth operational amplifier; one end of the twelfth resistor is connected to the connection point of the tenth resistor and the fifth capacitor, and the other end is grounded; one end of the thirteenth resistor is connected to the non-inverting input terminal of the sixth operational amplifier, and the other end is grounded; one end of the fourth capacitor is connected to the connection point of the ninth resistor and the tenth resistor, and the other end is grounded; the third capacitor is connected to the eighth resistor in parallel; one end of the sixth capacitor is connected to the connection point of the tenth resistor and the fifth capacitor; the output terminal of the sixth operational amplifier outputs the sinusoidal wave voltage signal.

6. The impedance setting circuit according to claim 2, characterized in that: The control signal includes a first control signal and a second control signal; The skin impedance interference circuit comprises: an analog switch, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor and an adjustable resistor; The signal input end of the analog switch is connected to the first control signal sent by the control circuit, and the multiple output ends are respectively connected to one end of the seventh capacitor, the eighth capacitor, the ninth capacitor and the tenth capacitor, and the other ends of the seventh capacitor, the eighth capacitor, the ninth capacitor and the tenth capacitor are all connected to the output end of the impedance generating circuit, and the analog switch adjusts the capacitance of the seventh capacitor, the eighth capacitor, the ninth capacitor and the tenth capacitor according to the first control signal; The signal input end of the adjustable resistor is connected to the second control signal sent by the control circuit, the first signal output end of the adjustable resistor is connected to the common end of the analog switch, and the second output end is connected to the output end of the impedance generating circuit.

7. The impedance setting circuit according to claim 1, characterized in that: The signal conversion circuit comprises: A first constant current source circuit, used for converting the sinusoidal wave voltage signal into the first current signal; A second constant current source circuit is used for converting the second voltage signal into the second current signal.

8. The impedance setting circuit according to claim 7, characterized in that: The first constant current source circuit comprises: a seventh operational amplifier, an eighth operational amplifier, a fourteenth resistor, a fifteenth resistor and a sixteenth resistor; The non-inverting input terminal of the seventh operational amplifier is connected to the sinusoidal wave voltage signal, and the inverting input terminal and the non-inverting input terminal of the seventh operational amplifier are both connected to the non-inverting input terminal of the eighth operational amplifier; the inverting input terminal and the output terminal of the eighth operational amplifier are both connected to the non-inverting input terminal of the seventh operational amplifier; the fourteenth resistor is connected between the output terminal of the seventh operational amplifier and the non-inverting input terminal of the eighth operational amplifier; the fifteenth resistor is connected between the inverting input terminal and the output terminal of the seventh operational amplifier; the sixteenth resistor is connected between the output terminal of the eighth operational amplifier and the non-inverting input terminal of the seventh operational amplifier.

9. The impedance setting circuit according to claim 7, characterized in that: The second constant current source circuit comprises: a ninth operational amplifier, a tenth operational amplifier, a seventeenth resistor, an eighteenth resistor and a nineteenth resistor; The non-inverting input terminal of the ninth operational amplifier is connected to the second voltage signal, and the inverting input terminal and the non-inverting input terminal of the ninth operational amplifier are both connected to the non-inverting input terminal of the tenth operational amplifier; the inverting input terminal and the output terminal of the tenth operational amplifier are both connected to the non-inverting input terminal of the ninth operational amplifier; the seventeenth resistor is connected between the output terminal of the ninth operational amplifier and the non-inverting input terminal of the tenth operational amplifier; the eighteenth resistor is connected between the inverting input terminal and the output terminal of the ninth operational amplifier; the nineteenth resistor is connected between the output terminal of the tenth operational amplifier and the non-inverting input terminal of the ninth operational amplifier.

10. The impedance setting circuit according to claim 1, characterized in that: The impedance generating circuit comprises: a first light emitting diode, a second light emitting diode, a first phototransistor and a second phototransistor; The anode of the first light emitting diode is connected to the second current signal, and the cathode is grounded; The anode of the second light emitting diode is connected to the above, and the cathode is grounded; The collector of the first phototransistor is connected to the monitoring device to receive the detection voltage applied by the monitoring device; the emitter of the first phototransistor is connected to the collector of the second phototransistor, and the emitter of the second phototransistor is grounded; The first phototransistor receives light emitted by the first light-emitting diode and changes its own impedance according to the intensity of the light; the second phototransistor receives light emitted by the second light-emitting diode and changes its own impedance according to the intensity of the light.

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