RU2690112C1 - Usb-device for recording electrocardiograms - Google Patents

Abstract

FIELD: medicine.SUBSTANCE: invention relates to electrocardiography, can be used for monitoring and diagnosing the human cardiovascular health in medical, sports practice, as well as in arbitrary conditions of human activity. USB device for recording electrocardiograms comprises analogue circuits for recording and primary processing of an ECG signal, analogue potentials common wire potential forming unit (V), analog circuits output matching unit with analogue-to-digital converter (ADC) input, microcontroller with USB-interface, having at least one built-in or external ADC with built-in or external multiplexer, microcontroller supply voltage generation unit. Device analogue circuits are powered from the unipolar power supply of a USB port of an external device, such as a computer, a smartphone or a tablet directly or through a separating device. Negative supply input of analogue circuits is connected to output of TOTAL (COM, GND), positive input of analogue circuits supply is connected to +Voutput, and common wire of analogue circuits is connected to output of circuit of potential formation of common wire of analogue circuits.EFFECT: simplified design and reduced dimensions, power consumption and heat release, reduced level of interference introduced by power supply source, possibility of using the invention with different types of external devices (computer, smartphone, tablet) directly or through a separating device owing to use of a unipolar power circuit.1 cl, 2 dwg

Description

The technical field to which the invention relates :

The invention relates to the field of medicine, in particular to electrocardiography and can be used to monitor and diagnose the state of the cardiovascular system of a person in medical, sports practice, as well as in arbitrary conditions of human activity.

The level of technology :

Known cardio monitor CardioQvark (patent number 162018 (RU). Cardio Monitor CardioQvark / Butkevich V.Kh., Usanov VA // 05/20/2016 [PM]), characterized by the fact that it is made in the form of a case for mobile devices, containing electric field sensors, each of which is connected to a differential amplifier and potentiometer controlled by a controller, connected to a crypto processor, power source, analog-to-digital converter (ADC) and transmitting information via a USB interface to a mobile device, while the ADC is capable of receiving information ns of the differential amplifier.

The disadvantages of the cardiac monitor are the impossibility of registering other ECG leads, except for lead I, because of the location of the sensors directly in the case-casing, as well as the power supply made as a separate unit.

An ECG prefix to a personal computer is described (patent No. 2284144 (RU). An ECG prefix to a personal computer / A. Yu. Zhigulin // 09/27/2006 [RI]), containing a series-connected sensor unit, a switch, a noise compensator and analog a digital converter, a digital-to-analog converter, the output of which is connected to another input of a noise compensator, a serially connected interface, a communication channel made in the form of a radio channel, and a computer. Communication channel ECG set-top boxes can be performed by USB standard.

The disadvantage of the described device is that the generation of compensation signals for the constant component, as well as control signals for the switch and the noise compensator, is carried out by a computer, as well as the availability of its own power source and high energy consumption for information transmission over the radio channel.

The closest in technical essence is the electrocardiogram registration device (patent No. 48148 (RU). Electrocardiogram registration device / Akopyan IG // September 27, 2005 [PM]) (prototype) containing the interface and working parts, the interface part containing the controller interfaces, buffer random access memory and USB bus controller; the working part contains nine analog processing channels, three ADCs and an asynchronous data channel controller, which is connected to the specified interface controller via asin a chronic data transfer channel with galvanic decoupling, while the device additionally contains a secondary power supply with galvanic decoupling, and each of the nine specified analog processing channels contains series-connected overload protection, a buffer amplifier and a low-pass filter. The resolution of the used ADC microcircuits is 24 bits at a sampling frequency of 5 kHz per channel and an input signal range of ± 10 V.

The disadvantages of this device is the use of bipolar power, which increases the size and power consumption, and also causes noise through the use of an inverting inverter.

Disclosure of the invention :

The technical result of the proposed invention is to simplify the design and reduce the size, power consumption and heat dissipation, reduce the level of noise introduced by the power supply, ensure the device can be powered from the unipolar USB power of the external device port (computer, smartphone or tablet) directly or through a separating device through the use of unipolar power schemes.

This technical result is achieved due to the fact that the analog circuits of the device are powered from the unipolar USB power of the external device port (computer, smartphone or tablet) directly or via a separating device, while the negative voltage supply voltage of the analog circuits is connected to the COMM pin (COM, GND ), the positive input of the power supply of analog circuits - with the output + V _BUS , and the common wire of analog circuits - with the output circuit of the formation of the potential of the common wire of analog circuits. This allows you to abandon your own power supply and the use of an inverting converter (switching regulators) to form a negative potential of the bipolar supply voltage. The excluded components have significant overall dimensions, their use causes an increase in energy consumption and, as a result, heat generation. The absence of pulsed devices in the composition of the invention allows to reduce the level of noise introduced by the power source. The use of a unipolar supply voltage also allows the use of unipolar ADCs, for example, internal ADCs of the microcontroller or unipolar ADCs of high capacity, which allows us to simplify analog circuits by replacing analogue filters with digital ones. The possibility of using the device with different types of external devices (computer, smartphone, tablet) is achieved by using the USB bus.

Brief Description of the Drawings :

Figure 1 - structural diagram of the device

Figure 2 - Display of the output range of analog circuits on the input range of the ADC

The implementation of the invention :

The figure 1 presents the structural diagram of the device.

The USB device for recording electrocardiograms contains analog circuits for recording and preprocessing the ECG signal 1, a common wire potential generation unit (V _COMM ) analog circuits 2, an analog circuit output matching unit with an analog-to-digital converter input (ADC) 4, a microcontroller with USB interface 5, having at least one built-in or external ADC with built-in or external multiplexer, the unit forming the supply voltage of the microcontroller 3.

USB device registration electrocardiogram works as follows. Analog biopotentials from cardioelectrodes fixed at certain points of the human body are fed to the input of analog recording and preprocessing ECG-signal circuits 1. The pre-processed ECG signal from the output of analog circuits 1 is provided by the output matching circuit of analog circuits with the ADC input 4 to the input range of the external or A built-in ADC microcontroller according to figure 2. The choice of a specific lead of an ECG signal is made by an external multiplexer or built into the ADC. Further digital processing and transmission of the ECG signal to an external device (computer, smartphone or tablet) is carried out by the microcontroller 5.

The circuit contains the following supply voltage:

- a common wire - zero potential connected to the conductor zero USB bus potential, ground potential power the microcontroller 5, an input negative potential power analog circuits 1 and zero power supply potential formation potential VA _GEN analog circuits 3 and the block matching output analog circuits to the input ADC 4.

- + V _BUSES - power supply potential of the device connected to the +5 V potential wire of the USB bus, the input of the power supply voltage shaping unit of the microcontroller 3, the positive potential power input of the analog circuits 1 and the input of the voltage shaping unit VA _Common analog circuits 2.

- + V _BUSES / 2 - median potential, connected to the common wire of analog circuits.

- + V _MK - the potential power supply of the microcontroller 3, digital circuits of the ADC and multiplexer, formed by the unit forming the supply voltage of the microcontroller 3.

Claims (1)

USB electrocardiogram recorder containing analog ECG signal recording and preprocessing circuits, a common wire potential generating unit (V ОБЩ) analog circuits, an analog circuit output matching unit with an analog-to-digital converter (ADC) input, a microcontroller with a USB interface, having at least one built-in or external ADC with a built-in or external multiplexer, a microcontroller supply voltage shaping unit, characterized in that the analog circuits supply the device I am from a unipolar USB power port of an external device, such as a computer, smartphone or tablet, directly or through a separating device, while the input supply voltage of the negative supply voltage of analog circuits is connected to the COMM pin (COM, GND), the positive power input of analog circuits is connected to + VShINY, and the common wire of analog circuits - with the output circuit of the formation of the potential of the common wire of analog circuits.

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