CN210144636U - Human pulse wave detection circuit and wearable pulse measurer - Google Patents
Human pulse wave detection circuit and wearable pulse measurer Download PDFInfo
- Publication number
- CN210144636U CN210144636U CN201822078497.5U CN201822078497U CN210144636U CN 210144636 U CN210144636 U CN 210144636U CN 201822078497 U CN201822078497 U CN 201822078497U CN 210144636 U CN210144636 U CN 210144636U
- Authority
- CN
- China
- Prior art keywords
- resistor
- operational amplifier
- led lamp
- module
- amplification unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)
Abstract
A human body pulse wave detection circuit and a wearable pulse measurer comprise a main control module, a driving circuit module, a light emitting module, a receiving module and an amplifying circuit module, wherein the main control module is used for outputting a first pulse width modulation signal and a second pulse width modulation signal, the driving circuit module is used for generating driving current according to the first pulse width modulation signal, the light emitting module is used for emitting light to human body tissues according to the driving current, the receiving module is used for receiving the reflected light of the human body tissues to generate current signals, the amplifying circuit module is used for generating a second current signal according to the current signals and generating pulse wave voltage signals according to the second pulse width modulation signal, the main control module is also used for generating a second pulse width modulation signal according to the second current signals, so that the light emitting module can provide a stable light source in a motion state, and the stability of the waveform of an original PPG signal is improved, and further, the amplifying circuit module can output high-precision pulse wave data, and influence caused by artifact movement is avoided.
Description
Technical Field
The utility model belongs to the technical field of medical equipment, especially, relate to a human pulse wave detection circuitry and wearable pulse measurement ware.
Background
At present, a light-emitting LED is used to irradiate human skin, and a photodiode is used to measure a reflected light intensity change caused by blood flow to obtain a PPG (photoplethysmography) signal for estimating a heart rate, however, the PPG signal is greatly affected by poor blood perfusion, ambient light and motion artifacts, especially motion artifacts, due to relative motion between the human skin and a pulse wave measurer during motion, not only external light is irradiated to a light receiver from a gap, but also a path from the light-emitting LED irradiating the human skin to the light receiver is changed, so that the light receiver receives light reflected by the human skin, and further heart rate measurement accuracy is affected.
Therefore, the human pulse wave detection circuit in the conventional technical scheme has the problem of low heart rate measurement accuracy caused by the influence of motion artifacts.
SUMMERY OF THE UTILITY MODEL
The utility model provides a human pulse wave detection circuitry and wearable pulse caliber aims at solving the human pulse wave detection circuitry among the traditional technical scheme and has the influence that receives the motion artifact and cause the problem that rhythm of the heart measurement accuracy is low.
The utility model discloses a realize like this, a human pulse wave detection circuitry, include:
the main control module is used for outputting a first pulse width modulation signal;
the driving circuit module is connected with the main control module and used for generating driving current according to the first pulse width modulation signal;
the light emitting module is connected with the driving circuit module and used for emitting light to human tissues according to the driving current;
the receiving module is used for receiving the reflected light of the human tissue to generate a current signal; and
the amplifying circuit module is connected with the main control module and the receiving module and used for generating a second current signal according to the current signal and generating a pulse wave voltage signal according to a second pulse width modulation signal;
in one embodiment, the amplifying circuit module includes: the first-stage amplification unit is connected with the receiving module and used for generating a first current signal according to the current signal;
the second-stage amplification unit is connected with the first-stage amplification unit and the main control module and used for generating a second current signal according to the first current signal so that the main control module outputs the second pulse width modulation signal according to a direct current component in the second current signal;
the level adjusting unit is connected with the main control module and used for generating a third current signal for compensating the direct current component in the second current signal according to the second pulse width modulation signal; and
and the third-stage amplification unit is connected with the second-stage amplification unit, the level adjustment unit and the main control module and is used for compensating the direct current component in the second current signal according to the third current signal so as to generate the pulse wave voltage signal.
In one embodiment, the first stage amplifying unit includes: the circuit comprises a first operational amplifier, a second operational amplifier, a first capacitor, a second capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor; the homodromous input end of the first-stage amplification unit is connected with a first reference voltage signal, the homodromous input end of the second-stage amplification unit is connected with a second reference voltage signal, the inverting input end of the first operational amplifier, the first end of the first capacitor and the first end of the second resistor are connected in common to form the first input end of the first-stage amplification unit, the output end of the first operational amplifier, the second end of the first capacitor and the first end of the first resistor are connected in common, the second end of the first resistor and the second end of the second resistor are connected in common to form the first output end of the first-stage amplification unit, the inverting input end of the second operational amplifier, the first end of the second capacitor and the first end of the fourth resistor are connected in common to form the second input end of the first-stage amplification unit, and the output end of the second operational amplifier, The second end of the second capacitor and the first end of the third resistor are connected in common, and the second end of the third resistor and the second end of the fourth resistor are connected in common to form a second output end of the first amplifying unit.
In one embodiment, the second-stage amplifying unit includes: the third operational amplifier, the fifth resistor, the sixth resistor, the seventh resistor and the eighth resistor; the first end of the fifth resistor is a first input end of the second-stage amplification unit, the first input end of the sixth resistor is a second input end of the second-stage amplification unit, the second end of the fifth resistor and the first end of the eighth resistor are connected to the non-inverting input end of the third operational amplifier in common, the second end of the eighth resistor is connected to a third reference voltage signal in common, the second end of the sixth resistor and the first end of the seventh resistor are connected to the inverting input end of the third operational amplifier in common, and the second end of the seventh resistor and the output end of the third operational amplifier are connected to form an output end of the second amplification unit in common.
In one embodiment, the level adjustment unit includes: a fourth operational amplifier, a third capacitor and a ninth resistor; the first end of the ninth resistor is the input end of the level adjustment unit, the second end of the ninth resistor and the first end of the third capacitor are connected to the non-inverting input end of the fourth operational amplifier in common, the second end of the third capacitor is connected to the ground, and the inverting input end of the fourth operational amplifier and the output end of the fourth operational amplifier are connected to form the output end of the level adjustment unit in common.
In one embodiment, the third stage amplifying unit includes: a fifth operational amplifier, a fourth capacitor, a tenth resistor, an eleventh resistor, a twelfth resistor and a thirteenth resistor; a first end of the tenth resistor is a first input end of the third amplifying unit, a first end of the eleventh resistor is a second input end of the third amplifying unit, a second end of the eleventh resistor and a first end of the twelfth resistor are commonly connected to a non-inverting input end of the fifth operational amplifier, a second end of the twelfth resistor is connected to ground, a second end of the tenth resistor, a first end of the thirteenth resistor and a first end of the fourth capacitor are commonly connected to an inverting input end of the fifth operational amplifier, and an output end of the fifth operational amplifier, a second end of the thirteenth resistor and a second end of the fourth capacitor are commonly connected to form an output end of the third amplifying unit.
In one embodiment, the driving circuit module includes: the first operational amplifier, the first field effect transistor, the fifth capacitor, the fourteenth resistor, the fifteenth resistor and the sixteenth resistor are connected in series; the non-inverting input terminal of the sixth operational amplifier is the input terminal of the driving circuit module, the first terminal of the fifth capacitor, the first terminal of the fifteenth resistor, the first terminal of the sixteenth resistor, and the output terminal of the first field-effect transistor are commonly connected to the inverting input terminal of the sixth operational amplifier, the output terminal of the sixth operational amplifier, the second terminal of the fifth capacitor, and the first terminal of the fourteenth resistor are commonly connected, the second terminal of the fourteenth resistor, the second terminal of the fifteenth resistor, and the control terminal of the first field-effect transistor are commonly connected, the second terminal of the sixteenth resistor is connected to the ground, and the input terminal of the first field-effect transistor is the driving output terminal of the driving circuit module.
In one embodiment, the light emitting module includes: the LED lamp comprises a first LED lamp, a second LED lamp, a third LED lamp, a fourth LED lamp, a fifth LED lamp, a sixth LED lamp, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a twenty-first resistor and a twenty-second resistor; the positive pole of first LED lamp, the positive pole of second LED lamp, the positive pole of third LED lamp, the positive pole of fourth LED lamp, the positive pole of fifth LED lamp and the positive pole of sixth LED lamp connects the constitution altogether the power input end of light emitting module, the negative pole of first LED lamp with the first end of seventeenth resistance is connected, the negative pole of second LED lamp with the first end of eighteenth resistance is connected, the negative pole of third LED lamp with the first end of nineteenth resistance is connected, the negative pole of fourth LED lamp with the first end of twentieth resistance is connected, the negative pole of fifth LED lamp with the first end of twenty-first resistance is connected, the negative pole of sixth LED lamp with the first end of twenty-second resistance is connected, the second end of seventeenth resistance, the second end of eighteenth resistance, the second end of nineteenth resistance, And the second end of the twentieth resistor, the second end of the twenty-first resistor and the second end of the twenty-second resistor are connected in common to form a driving input end of the light-emitting module.
In one embodiment, the receiving module includes: and the anode of the first diode is the first end of the receiving module, and the cathode of the first diode is the second end of the receiving module.
In addition, still provide a wearing formula pulse measurement ware, include from bottom to top in proper order:
the PCB board is used for printing the human body pulse wave detection circuit;
the driving circuit module and the amplifying circuit module are arranged on the PCB;
the light-emitting modules are arranged to form a star-shaped symmetrical structure, and the receiving module is arranged in the middle of the light-emitting modules.
The human body pulse wave detection circuit outputs a first pulse width modulation signal through the main control module, so that the driving circuit module generates driving current according to the first pulse width modulation signal to drive the light emitting module to emit light to human body tissues, and the receiving module receives reflected light of the human body tissues to generate current signals; the amplification circuit module generates a second current signal according to the current signal, so that the main control module generates a second pulse width modulation signal according to a direct current component in the second current signal, the amplification circuit module generates a pulse wave voltage signal according to the second current signal and the second pulse width modulation signal, the light emitting module can provide a stable light source in a motion state, the stability of an original PPG signal waveform is improved, and the amplification circuit module can output high-precision pulse wave data.
Drawings
Fig. 1 is a schematic block diagram of a human body pulse wave detection circuit according to an embodiment of the present invention;
fig. 2 is a schematic circuit diagram of a human body pulse wave detection circuit according to another embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of 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 merely illustrative of the invention and are not intended to limit the invention.
Fig. 1 is a schematic block diagram of a human body pulse wave detection circuit according to a preferred embodiment of the present invention, which only shows the relevant parts of the present embodiment for convenience of description, and the detailed description is as follows:
referring to fig. 1 and 2, a human pulse wave detecting circuit includes: the main control module 10, the driving circuit module 20, the light emitting module 30, the receiving module 40 and the amplifying circuit module 50.
The main control module 10 is configured to output a first pulse width modulation signal; the driving circuit module 20 is connected with the main control module 10 and is used for generating a driving current according to the first pulse width modulation signal; the light emitting module 30 is connected to the driving circuit module 20, and is configured to emit light to human tissue according to the driving current; the receiving module 40 is used for receiving the reflected light of the body tissue to generate a current signal; the amplifying circuit module 50 is connected to the main control module 10 and the receiving module 40, and configured to generate a second current signal according to the current signal and generate a pulse wave voltage signal according to a second pulse width modulation signal, and the main control module is further configured to generate a second pulse width modulation signal according to the second current signal.
In this embodiment, the main control module 10 outputs a first pulse width modulation signal, so that the driving circuit module 20 generates a driving current according to the first pulse width modulation signal to drive the light emitting module 30 to emit light to human tissue, and the receiving module 40 receives the reflected light of the human tissue to generate a current signal; make amplifier circuit module 50 generate the second current signal according to the current signal to make main control module 10 generate the second pulse width modulation signal according to the direct current composition in the second current signal, thereby make amplifier circuit module 50 generate the pulse wave voltage signal according to second current signal and second pulse width modulation signal, make light emitting module 30 can provide stable light source under the motion state, thereby improve the stability of original PPG signal waveform, and then make amplifier circuit module 50 can output the pulse wave data of high accuracy.
In one embodiment, referring to fig. 2, the amplifying circuit block 50 includes: a first-stage amplification unit 501, a second-stage amplification unit 502, a level adjustment unit 503, and a third-stage amplification unit 504. The first-stage amplifying unit 501 is connected to the receiving module 40, and is configured to generate a first current signal according to the current signal; the second-stage amplifying unit 502 is connected to the first-stage amplifying unit 501 and the main control module 10, and is configured to generate a second current signal according to the first current signal, so that the main control module 10 outputs a second pulse width modulation signal according to a direct current component of the second current signal; the level adjustment unit 503 is connected to the main control module 10, and configured to generate a third current signal for compensating a dc component in the second current signal according to the second pulse width modulation signal; the third-stage amplifying unit 504 is connected to the second-stage amplifying unit 502, the level adjusting unit 503 and the main control module 10, and is configured to compensate the dc component in the second current signal according to the second current signal to generate a pulse wave voltage signal. Because the current signal output by the receiving module 40 includes a dc component and an ac component, and the dc component in the current signal cannot dynamically describe the human pulse wave signal, the first-stage amplifying unit 501 of this embodiment outputs the first current signal after performing the first-stage amplification processing on the weak current signal output by the receiving module 40, and outputs the second current signal after performing the amplification processing by the second-stage amplifying circuit 502, so that the main control module 10 outputs the second pulse width modulation signal according to the dc component of the second current signal, so that the level adjusting unit 503 outputs the third current signal capable of compensating the dc component in the second current signal according to the duty ratio of the second pulse width modulation signal, and further the third-stage amplifying circuit 504 subtracts the third current signal according to the second current signal, that is, cancels the dc component in the current signal output by the receiving module 40, so as to output a pulse wave voltage signal capable of dynamically reflecting the human pulse wave, thereby more truly reflecting the human pulse wave signal.
In one embodiment, referring to fig. 2, the first-stage amplification unit 501 includes: a first operational amplifier A1, a second operational amplifier A2, a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4; the same-direction input end of the first-stage amplification unit 501 is connected with a first reference voltage signal, the same-direction input end of the second-stage amplification unit 502 is connected with a second reference voltage signal, the inverting input end of the first operational amplifier A1, the first end of the first capacitor C1 and the first end of the second resistor R2 are connected in common to form the first input end of the first-stage amplification unit 501, the output end of the first operational amplifier A1, the second end of the first capacitor C1 and the first end of the first resistor R1 are connected in common, the second end of the first resistor R1 and the second end of the second resistor R2 are connected in common to form the first output end of the first-stage amplification unit 501, the inverting input end of the second operational amplifier A2, the first end of the second capacitor C2 and the first end of the fourth resistor R4 are connected in common to form the second input end of the first-stage amplification unit 501, the output end of the second operational amplifier A2, the second end of the second capacitor C2 and the first end of the third resistor R3 are connected in common, the second terminal of the third resistor R3 and the second terminal of the fourth resistor R4 are commonly connected to form a second output terminal of the first amplifying unit. The first-stage amplification unit 501 of this embodiment performs first-stage amplification on a weak current signal to generate a first current signal.
In one embodiment, referring to fig. 2, the second-stage amplifying unit 502 includes: a third operational amplifier a3, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8; a first end of the fifth resistor R5 is a first input end of the second-stage amplification unit 502, a first input end of the sixth resistor R6 is a second input end of the second-stage amplification unit 502, a second end of the fifth resistor R5 and a first end of the eighth resistor R8 are commonly connected to a non-inverting input end of the third operational amplifier A3, a second end of the eighth resistor R8 is connected to the third reference voltage signal, a second end of the sixth resistor R6 and a first end of the seventh resistor R7 are commonly connected to an inverting input end of the third operational amplifier A3, and a second end of the seventh resistor R7 and an output end of the third operational amplifier A3 are commonly connected to form an output end of the second amplification unit. The second-stage amplification unit 502 of the present embodiment performs two-stage amplification on the first current signal to generate a second current signal.
In one embodiment, referring to fig. 2, the level adjustment unit 503 includes: a fourth operational amplifier, a third capacitor and a ninth resistor; a first end of the ninth resistor is an input end of the level adjustment unit 503, a second end of the ninth resistor and a first end of the third capacitor are commonly connected to a non-inverting input end of the fourth operational amplifier, a second end of the third capacitor is connected to ground, and an inverting input end of the fourth operational amplifier and an output end of the fourth operational amplifier are commonly connected to form an output end of the level adjustment unit 503. The level adjustment unit 503 of this embodiment outputs a third current signal according to the second pulse width modulation signal output by the main control module 10, so as to perform dc compensation on the second current signal, so that the third-stage amplification unit 504 outputs a pulse wave voltage signal suitable for being collected by the main control module 10.
In one embodiment, referring to fig. 2, the third-stage amplifying unit 504 includes: a fifth operational amplifier a5, a fourth capacitor C4, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12 and a thirteenth resistor R13; a first end of the tenth resistor R10 is a first input end of the third amplifying unit, a first end of the eleventh resistor R11 is a second input end of the third amplifying unit, a second end of the eleventh resistor R11 and a first end of the twelfth resistor R12 are commonly connected to a non-inverting input end of the fifth operational amplifier a5, a second end of the twelfth resistor R12 is connected to ground, a second end of the tenth resistor R10, a first end of the thirteenth resistor R13 and a first end of the fourth capacitor C4 are commonly connected to an inverting input end of the fifth operational amplifier a5, and an output end of the fifth operational amplifier a5, a second end of the thirteenth resistor R13 and a second end of the fourth capacitor C4 are commonly connected to form an output end of the third amplifying unit.
In one embodiment, referring to fig. 2, the driving circuit module 20 includes: a sixth operational amplifier a6, a first field effect transistor Q1, a fifth capacitor C5, a fourteenth resistor R14, a fifteenth resistor R15 and a sixteenth resistor R16; a non-inverting input terminal of the sixth operational amplifier a6 is an input terminal of the driving circuit module 20, a first terminal of the fifth capacitor C5, a first terminal of the fifteenth resistor R15, a first terminal of the sixteenth resistor R16, and an output terminal of the first field-effect transistor Q1 are commonly connected to an inverting input terminal of the sixth operational amplifier a6, an output terminal of the sixth operational amplifier a6, a second terminal of the fifth capacitor C5, and a first terminal of the fourteenth resistor R14 are commonly connected, a second terminal of the fourteenth resistor R14, a second terminal of the fifteenth resistor R15, and a control terminal of the first field-effect transistor Q1 are commonly connected, a second terminal of the sixteenth resistor R16 is connected to ground, and an input terminal of the first field-effect transistor Q1 is a driving output terminal of the driving circuit module 20. In a specific embodiment, the first fet Q1 is an N-type fet, and the gate, source and drain of the N-type fet are the control terminal, output terminal and input terminal of the first fet Q1, respectively. The driving circuit module 20 of this embodiment can adjust the driving current according to the duty ratio output by the pulse width modulation signal output by the main control module 10, so as to control the brightness of the LED lamp set of the light emitting module 30.
In one embodiment, referring to fig. 2, the light emitting module 30 includes: a first LED lamp LED1, a second LED lamp LED2, a third LED lamp LED3, a fourth LED lamp LED4, a fifth LED lamp LED5, a sixth LED lamp LED6, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, and a twenty-second resistor R22; the anode of the first LED lamp LED1, the anode of the second LED lamp LED2, the anode of the third LED lamp LED3, the anode of the fourth LED lamp LED4, the anode of the fifth LED lamp LED5 and the anode of the sixth LED lamp LED6 are connected in common to form a power input end of the light emitting module 30, the negative electrode of the first LED lamp LED1 is connected with the first end of a seventeenth resistor R17, the negative electrode of the second LED lamp LED2 is connected with the first end of an eighteenth resistor R18, the negative electrode of the third LED lamp LED3 is connected with the first end of a nineteenth resistor R19, the negative electrode of the fourth LED lamp LED4 is connected with the first end of a twentieth resistor R20, the negative electrode of the fifth LED lamp LED5 is connected with the first end of a twenty-first resistor R21, the negative electrode of the sixth LED lamp LED6 is connected with the first end of a twenty-second resistor R22, the second end of the seventeenth resistor R17, the second end of the eighteenth resistor R18, the second end of the nineteenth resistor R19, the second end of the twentieth resistor R20, the second end of the twenty-first resistor R21 and the second end of the twenty-second resistor R22 are commonly connected to form a driving input terminal of the light emitting module 30. The first LED lamp LED1, the second LED lamp LED2, the third LED lamp LED3, the fourth LED lamp LED4, the fifth LED lamp LED5, and the sixth LED lamp LED6 of the present embodiment are arranged in a star-shaped symmetrical structure. In other embodiments, the light emitting module 30 may be 2 LED lamps, and may also be 3 or 4 LED lamps. The light emitting module 30 may emit red light, green light, or dual light. This embodiment light emitting module 30 includes the LED lamp that 6 star type symmetrical structure arranged, when the user moves, through the reflected emission light of the LED lamp of receiving 6 star type symmetrical structure arrangements, the great defect of single LED lamp reflected emission light fluctuation has been avoided, reflected light's stability has been improved, so receive the influence of motion little, make the LED banks can provide stable light source under the motion state, thereby improve the stability of original PPG signal waveform, human pulse wave signal's measurement accuracy has been improved.
In one embodiment, referring to fig. 2, the receiving module 40 includes a first diode D1, the anode of the first diode D1 is the first terminal of the receiving module 40, and the cathode of the first diode D1 is the second terminal of the receiving module 40. The first diode D1 of the present embodiment is implemented to receive reflected light rays of human tissue and convert the reflected light rays into a current signal.
In addition, still provide a wearing formula pulse measurement ware, include from bottom to top in proper order: the PCB board is used for printing the human body pulse wave detection circuit; a driving circuit module 20 and an amplifying circuit module 50 printed on the PCB; the light emitting modules 30 are arranged to form a star-shaped symmetrical structure, and the receiving module 40 is disposed at the middle position of the light emitting modules 30. The light emitting module 30 of this embodiment is a star-shaped symmetric structure, and is little affected by movement, so that the light emitting module 30 can provide a stable light source in a moving state, thereby improving the stability of the original PPG signal waveform and improving the measurement accuracy of the human pulse wave signal.
The operation principle of the human body pulse wave detection circuit of the present invention will be described below with reference to fig. 2 as an example, which is detailed as follows:
a first PWM output end LED _ EN of the main control module 10 outputs a first pulse width modulation signal to a non-inverting input end of a sixth operational amplifier a6, so that the sixth operational amplifier a6 controls on/off of a first field effect transistor according to a duty ratio of the first pulse width modulation signal to adjust a driving current for driving a first LED lamp, a second LED lamp, a third LED lamp, a fourth LED lamp, a fifth LED lamp, and a sixth LED lamp to light or to emit light to a human tissue, a first diode D1 receives reflected light reflected by the human tissue to generate a current signal and outputs the current signal to an inverting input end of the first operational amplifier a1 and an inverting input end of the second operational amplifier a2, the first operational amplifier a1 and the second operational amplifier a2 generate a first current signal according to the current signal and output the first current signal to the third operational amplifier A3, the third operational amplifier A3 generates a second current signal according to the first current signal, and simultaneously outputs the second current signal to the current feedback terminal SIG _ DC of the main control module 10 and the inverting input terminal of the fifth operational amplifier a5, respectively, the main control module 10 outputs a second PWM signal through the second PWM output terminal SIG _ AC according to the second current signal to the non-inverting input terminal of the fourth operational amplifier a4, the fourth operational amplifier a4 generates a third current signal according to the second PWM signal and outputs the third current signal to the non-inverting input terminal of the fifth operational amplifier a5, and the fifth operational amplifier a5 generates a pulse wave voltage signal according to the second current signal and the third current signal, and feeds the pulse wave voltage signal back to the signal detection terminal SIG _ AC of the main control module 10, so that the pulse wave signal of the tested human tissue can be displayed.
The invention has the beneficial effects that:
the main control module outputs a first pulse width modulation signal and a second pulse width modulation signal, so that the driving circuit module generates driving current according to the first pulse width modulation signal to drive the light emitting module to emit light to human tissues, and the receiving module receives reflected light of body tissues to generate current signals; the amplification circuit module generates a pulse wave voltage signal according to the current signal and the second pulse width modulation signal, so that the light emitting module can provide a stable light source in a motion state, the stability of the waveform of the original PPG signal is improved, and the amplification circuit module can output high-precision pulse wave data.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. A human pulse wave detection circuit, comprising:
the main control module is used for outputting a first pulse width modulation signal;
the driving circuit module is connected with the main control module and used for generating driving current according to the first pulse width modulation signal;
the light emitting module is connected with the driving circuit module and used for emitting light to human tissues according to the driving current;
the receiving module is used for receiving the reflected light of the human tissue to generate a current signal; and
the amplifying circuit module is connected with the main control module and the receiving module and used for generating a second current signal according to the current signal and generating a pulse wave voltage signal according to a second pulse width modulation signal;
the main control module is further configured to generate the second pulse width modulation signal according to the second current signal.
2. The human pulse wave detection circuit of claim 1, wherein the amplification circuit module comprises:
the first-stage amplification unit is connected with the receiving module and used for generating a first current signal according to the current signal;
the second-stage amplification unit is connected with the first-stage amplification unit and the main control module and used for generating a second current signal according to the first current signal so that the main control module outputs the second pulse width modulation signal according to a direct current component in the second current signal;
the level adjusting unit is connected with the main control module and used for generating a third current signal for compensating the direct current component in the second current signal according to the second pulse width modulation signal; and
and the third-stage amplification unit is connected with the second-stage amplification unit, the level adjustment unit and the main control module and is used for compensating the direct current component in the second current signal according to the third current signal so as to generate the pulse wave voltage signal.
3. The human pulse wave detection circuit of claim 2, wherein the first stage amplification unit comprises: the circuit comprises a first operational amplifier, a second operational amplifier, a first capacitor, a second capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor;
the homodromous input end of the first-stage amplification unit is connected with a first reference voltage signal, the homodromous input end of the second-stage amplification unit is connected with a second reference voltage signal, the inverting input end of the first operational amplifier, the first end of the first capacitor and the first end of the second resistor are connected in common to form the first input end of the first-stage amplification unit, the output end of the first operational amplifier, the second end of the first capacitor and the first end of the first resistor are connected in common, the second end of the first resistor and the second end of the second resistor are connected in common to form the first output end of the first-stage amplification unit, the inverting input end of the second operational amplifier, the first end of the second capacitor and the first end of the fourth resistor are connected in common to form the second input end of the first-stage amplification unit, and the output end of the second operational amplifier, And the second end of the second capacitor and the first end of the third resistor are connected in common, and the second end of the third resistor and the second end of the fourth resistor are connected in common to form a second output end of the first-stage amplification unit.
4. The human pulse wave detection circuit of claim 2, wherein the second stage amplification unit comprises: the third operational amplifier, the fifth resistor, the sixth resistor, the seventh resistor and the eighth resistor;
the first end of the fifth resistor is a first input end of the second-stage amplification unit, the first input end of the sixth resistor is a second input end of the second-stage amplification unit, the second end of the fifth resistor and the first end of the eighth resistor are connected to the non-inverting input end of the third operational amplifier in common, the second end of the eighth resistor is connected to a third reference voltage signal in common, the second end of the sixth resistor and the first end of the seventh resistor are connected to the inverting input end of the third operational amplifier in common, and the second end of the seventh resistor and the output end of the third operational amplifier are connected to form an output end of the second-stage amplification unit in common.
5. The human pulse wave detecting circuit according to claim 2, wherein the level adjusting unit comprises: a fourth operational amplifier, a third capacitor and a ninth resistor;
the first end of the ninth resistor is the input end of the level adjustment unit, the second end of the ninth resistor and the first end of the third capacitor are connected to the non-inverting input end of the fourth operational amplifier in common, the second end of the third capacitor is connected to the ground, and the inverting input end of the fourth operational amplifier and the output end of the fourth operational amplifier are connected to form the output end of the level adjustment unit in common.
6. The human pulse wave detection circuit according to claim 2, wherein the third-stage amplification unit comprises: a fifth operational amplifier, a fourth capacitor, a tenth resistor, an eleventh resistor, a twelfth resistor and a thirteenth resistor;
a first end of the tenth resistor is a first input end of the third-stage amplification unit, a first end of the eleventh resistor is a second input end of the third-stage amplification unit, a second end of the eleventh resistor and a first end of the twelfth resistor are commonly connected to a non-inverting input end of the fifth operational amplifier, a second end of the twelfth resistor is connected to ground, a second end of the tenth resistor, a first end of the thirteenth resistor and a first end of the fourth capacitor are commonly connected to an inverting input end of the fifth operational amplifier, and an output end of the fifth operational amplifier, a second end of the thirteenth resistor and a second end of the fourth capacitor are commonly connected to form an output end of the third-stage amplification unit.
7. The human pulse wave detection circuit of claim 1, wherein the light emitting module comprises: the LED lamp comprises a first LED lamp, a second LED lamp, a third LED lamp, a fourth LED lamp, a fifth LED lamp, a sixth LED lamp, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a twenty-first resistor and a twenty-second resistor;
the positive pole of first LED lamp, the positive pole of second LED lamp, the positive pole of third LED lamp, the positive pole of fourth LED lamp, the positive pole of fifth LED lamp and the positive pole of sixth LED lamp connects the constitution altogether the power input end of light emitting module, the negative pole of first LED lamp with the first end of seventeenth resistance is connected, the negative pole of second LED lamp with the first end of eighteenth resistance is connected, the negative pole of third LED lamp with the first end of nineteenth resistance is connected, the negative pole of fourth LED lamp with the first end of twentieth resistance is connected, the negative pole of fifth LED lamp with the first end of twenty-first resistance is connected, the negative pole of sixth LED lamp with the first end of twenty-second resistance is connected, the second end of seventeenth resistance, the second end of eighteenth resistance, the second end of nineteenth resistance, And the second end of the twentieth resistor, the second end of the twenty-first resistor and the second end of the twenty-second resistor are connected in common to form a driving input end of the light-emitting module.
8. The human pulse wave detection circuit of claim 1, wherein the driving circuit module comprises: the first operational amplifier, the first field effect transistor, the fifth capacitor, the fourteenth resistor, the fifteenth resistor and the sixteenth resistor are connected in series;
the non-inverting input terminal of the sixth operational amplifier is the input terminal of the driving circuit module, the first terminal of the fifth capacitor, the first terminal of the fifteenth resistor, the first terminal of the sixteenth resistor, and the output terminal of the first field-effect transistor are commonly connected to the inverting input terminal of the sixth operational amplifier, the output terminal of the sixth operational amplifier, the second terminal of the fifth capacitor, and the first terminal of the fourteenth resistor are commonly connected, the second terminal of the fourteenth resistor, the second terminal of the fifteenth resistor, and the control terminal of the first field-effect transistor are commonly connected, the second terminal of the sixteenth resistor is connected to the ground, and the input terminal of the first field-effect transistor is the driving output terminal of the driving circuit module.
9. The human pulse wave detection circuit of claim 1, wherein the receiving module comprises: and the anode of the first diode is the first end of the receiving module, and the cathode of the first diode is the second end of the receiving module.
10. The utility model provides a wearing formula pulse caliber which characterized in that includes from bottom to top in proper order:
a PCB board for printing the human body pulse wave detection circuit according to any one of claims 1 to 9;
the driving circuit module and the amplifying circuit module are arranged on the PCB;
the light-emitting modules are arranged to form a star-shaped symmetrical structure, and the receiving module is arranged in the middle of the light-emitting modules.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822078497.5U CN210144636U (en) | 2018-12-11 | 2018-12-11 | Human pulse wave detection circuit and wearable pulse measurer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822078497.5U CN210144636U (en) | 2018-12-11 | 2018-12-11 | Human pulse wave detection circuit and wearable pulse measurer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210144636U true CN210144636U (en) | 2020-03-17 |
Family
ID=69754185
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201822078497.5U Active CN210144636U (en) | 2018-12-11 | 2018-12-11 | Human pulse wave detection circuit and wearable pulse measurer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN210144636U (en) |
-
2018
- 2018-12-11 CN CN201822078497.5U patent/CN210144636U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10121815B2 (en) | Photo detector and associated integrated circuit | |
| CN103269550B (en) | LED ((Light Emitting Diode) current ripple elimination driving circuit | |
| CN106561068B (en) | Transmitter architecture for photoplethysmography systems | |
| WO2021098694A1 (en) | Ppg testing circuit and method, and wearable electronic device | |
| WO2019104827A1 (en) | Acquisition circuit, blood oxygen saturation acquisition chip and device | |
| US11278211B2 (en) | Apparatus and method for tracking and cancelling DC offset to acquire small AC signal using dual feedback loops | |
| TWI505588B (en) | Laser diode automatic stabilized optical power pulse driving device | |
| TWI434167B (en) | Automatic power control system, device, compensation voltage operation module and detection module | |
| WO2016045644A1 (en) | Bus bar current control circuit, constant-current driving controller and led light source | |
| CN107920787B (en) | Circuit arrangement for a light monitoring system and method for light monitoring | |
| CN210144636U (en) | Human pulse wave detection circuit and wearable pulse measurer | |
| US8093825B1 (en) | Control circuit for optical transducers | |
| Lee et al. | 22.3 A 141µW sensor SoC on OLED/OPD substrate for SpO2/ExG monitoring sticker | |
| JP2010233908A (en) | Pulse oximeter | |
| US9839086B2 (en) | Technique for adjusting the brightness of LED lamps | |
| Pandey et al. | A dual-channel PPG readout system with motion-tolerant adaptability for OLED-OPD sensors | |
| Zhang et al. | A low-power dynamic-range relaxed analog front end for wearable heart rate and blood oximetry sensor | |
| TWI461875B (en) | Optical power control system and its optical power control device | |
| CN203693603U (en) | Environment-light-interference-resisting blood oxygen measuring equipment | |
| TWI442811B (en) | Light source driving device | |
| US11464416B2 (en) | Measurement circuit, driving method, and electronic instrument | |
| US10568530B2 (en) | Apparatus and method for tracking and cancelling DC offset to acquire small AC signal | |
| CN106549572A (en) | A kind of circuit for generating negative voltage | |
| JP4962234B2 (en) | Pulse oximeter | |
| CN204169852U (en) | Be applicable to the Oximetry front end direct current filtering circuit of Intelligent bracelet |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20210219 Address after: C238, 2 / F, Institute of Tsinghua University, 019 Gaoxin South 7th Road, high tech Zone community, Yuehai street, Nanshan District, Shenzhen, Guangdong 518000 Patentee after: Shenzhen zhisuan Technology Co.,Ltd. Address before: Room 317, building 1, No.28, East 1st block, Jiansha Road, Danzao Town, Nanhai District, Foshan City, Guangdong Province 528200 Patentee before: Foshan Huikang Cloud Technology Co.,Ltd. |
|
| TR01 | Transfer of patent right |