Boost device for improving battery performance of electrotherapy device

Abstract

The application provides a voltage boosting device for improving battery performance of an electrotherapy device, comprising an inductor, a voltage boosting diode, a first comparator, a second comparator, a sampling unit, a driving unit, a transistor and a detection resistor; the first end of the inductor is connected with an input voltage, the second end is connected with the positive end of the voltage boosting diode and the collector of the transistor, the negative end of the voltage boosting diode is connected with an output voltage, the first input end of the first comparator is connected with a first reference voltage, the input end of the sampling unit is connected with the output voltage, the output end is connected with the second input end of the first comparator, the output end of the first comparator is connected with the first input end of the driving unit, the first input end of the second comparator is connected with a plurality of second reference voltages, the second input end is connected with the emitter of the transistor and the first end of the detection resistor, the output end is connected with the second input end of the driving unit, and the output end of the driving unit is connected with the base of the transistor. The application can well control the input current of the voltage boosting circuit and the current of the voltage boosting circuit at the starting moment.

Description

Technical Field

[0001] This invention belongs to the field of electrotherapy equipment design, and in particular relates to a booster device for improving the battery performance of electrotherapy equipment. Background Technology

[0002] Electrotherapy is a method of treating diseases using different types of electric current and electromagnetic fields. It mainly includes direct current electrotherapy, direct current iontophoresis, low-frequency pulse electrotherapy, medium-frequency pulse electrotherapy, high-frequency electrotherapy, and electrostatic therapy. Since the skin impedance of the human body is above 1KΩ, the pulse voltage of general electrotherapy equipment is around 50V to 100V; the output voltage of a standard button cell battery (CR2032) is 3V; to increase the voltage from 3V to above 50V, a DC-DC boost circuit is required.

[0003] A DC-DC boost circuit is a switching power supply that maintains a stable output by utilizing the on-time ratio of a switching transistor. It is widely used in electronic equipment across various industries due to its small size, lightweight design, and high efficiency, and is an indispensable power supply architecture. A DC-DC boost circuit mainly consists of a control circuit, a power inductor, and field-effect transistors (FETs). The control circuit can be constructed using dedicated ICs or discrete components. Figure 1 The diagram shows a basic DC-DC boost architecture, where L is an energy storage element. When the switch is closed, the voltage at point A is 0, and Vin directly charges the inductor L. The charging current path is shown in the diagram below. The switch conduction time dt = duty cycle * switching period = D * T.

[0004] like Figure 2 As shown, when the switch is open, the energy stored in L will discharge to the load through the diode; at the same time, Vin will also discharge to the load through the diode. The two are superimposed to achieve voltage boost. The discharge time dt = (1 - duty cycle) * switching period = (1 - D) * T.

[0005] like Figure 3 As shown, the inductor charges and discharges at the same rate during the two time intervals of the switch being closed and open; this is called the amplitude-second characteristic of the inductor. Rearranging, we get: Vout = Vin / (1-D).

[0006] Based on the characteristics of DC-DC boost circuits, they are very suitable for battery-powered electrotherapy equipment. However, since electrotherapy equipment generally uses button batteries (CR2032) for power supply, the output pulse current of a typical button battery is less than 20mA. With the current switching current of commonly used DC-DC boost chips reaching up to 1A, button batteries simply cannot meet the current requirements for output pulses, and button batteries cannot drive the boost circuit.

[0007] Therefore, it is essential to provide a boost circuit with low input current that is suitable for button cell battery power. Summary of the Invention

[0008] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a boost device for improving the battery performance of electrotherapy equipment, which solves the problem that button batteries in the prior art cannot meet the current requirements when outputting pulses and cannot drive the boost circuit.

[0009] To achieve the above and other related objectives, the present invention provides a boost device for improving the battery performance of an electrotherapy device. The boost device includes: an inductor, a boost diode, a first comparator, a data acquisition unit, a second comparator, a driving unit, a transistor, and a sensing resistor. The first terminal of the inductor is connected to the input voltage, and the second terminal is connected to the positive terminal of the boost diode and the collector of the transistor. The negative terminal of the boost diode is connected to the output voltage. The first input terminal of the first comparator is connected to a first reference voltage. The input terminal of the data acquisition unit is connected to the output voltage, and its output terminal is connected to the second input terminal of the first comparator. The output terminal of the first comparator is connected to the first input terminal of the driving unit. The first input terminal of the second comparator is connected to multiple second reference voltages, and its second input terminal is connected to the emitter of the transistor and the first terminal of the sensing resistor. Its output terminal is connected to the second input terminal of the driving unit, and the output terminal of the driving unit is connected to the base of the transistor. The second terminal of the sensing resistor is grounded.

[0010] Optionally, the acquisition unit includes a first voltage divider resistor and a second voltage divider resistor. The first end of the first voltage divider resistor is connected to the output voltage, the second end is connected to the first end of the second voltage divider resistor and the second input end of the first comparator, and the second end of the second voltage divider resistor is grounded.

[0011] Optionally, the sensing resistor collects the input current flowing through the transistor. When the voltage across the sensing resistor is greater than the second reference voltage, the driving unit is enabled by the second comparator to limit the conduction time of the transistor, thereby controlling the input current of the transistor.

[0012] Optionally, the second reference voltage is 2.4mV to 2.5mV.

[0013] Optionally, the plurality of second reference voltages include a first voltage, a second voltage, and a third voltage that increase sequentially; when the voltage output by the acquisition unit to the first comparator is lower than the first voltage, the first comparator enables the driving unit to limit the conduction time of the transistor, thereby controlling the input current of the transistor; when the voltage output by the acquisition unit to the first comparator is higher than the second voltage, the first comparator enables the driving unit to turn off the limiting, so that the transistor conducts, but the sensing resistor and the second comparator remain operational; when the voltage output by the acquisition unit to the first comparator is higher than the third voltage, the driving unit stops waveform output and completes the boost.

[0014] Optionally, the first voltage is 0.5V to 0.7V, the second voltage is 0.9V to 1.1V, and the third voltage is 1.22V to 1.24V.

[0015] Optionally, the driving unit limits the conduction time of the transistor to no more than 400 ns and the switching frequency to below 1 MHz.

[0016] Optionally, the boost device further includes an input capacitor, with a first terminal connected to the input voltage and a second terminal grounded.

[0017] Optionally, the boost device further includes an output capacitor, with a first terminal connected to the output voltage and a second terminal grounded.

[0018] Optionally, a plurality of second reference voltages are generated by a reference voltage unit, one end of which is connected to the input voltage and the other end of which is connected to the first input terminal of the first comparator.

[0019] The present invention also provides an electrotherapy device, the electrotherapy device including a voltage boosting device as described in any of the above claims for improving the battery performance of the electrotherapy device.

[0020] As described above, the booster device of the present invention for improving the battery performance of electrotherapy equipment has the following beneficial effects:

[0021] This invention can effectively control the input current of a DC-DC boost circuit.

[0022] This invention can effectively control the current of a DC-DC boost circuit at startup.

[0023] The circuit of this invention is simple and easy to implement; the power consumption of this invention is low and the input current is small, which can extend the output life of button batteries; this invention has a boost effect, which simplifies the boost design of the power supply; this invention can be powered by button batteries, and the output power is limited, which can avoid the harm to the human body caused by excessive current, and has high safety. Attached Figure Description

[0024] Figure 1 The diagram shows a schematic of a DC-DC boost circuit.

[0025] Figures 2-3 The diagrams shown are schematics of DC-DC boost circuits.

[0026] Figure 4 The diagram shown is a structural block diagram of a booster device for improving the battery performance of an electrotherapy device, according to an embodiment of the present invention.

[0027] Figure 5 The diagram shown is a circuit structure schematic of a booster device for improving the battery performance of an electrotherapy device according to an embodiment of the present invention.

[0028] Component designation explanation

[0029] 101 Inductor

[0030] 102 Boost Diode

[0031] 103 First Comparator

[0032] 104 Acquisition Units

[0033] 105 Second Comparator

[0034] 106 drive units

[0035] 107 transistor

[0036] 108 Sensing Resistor

[0037] 109 Input capacitor

[0038] 110 Output capacitor Detailed Implementation

[0039] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0040] In the detailed description of embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged and not to scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0041] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include directions other than those depicted in the drawings for devices in use or operation. Furthermore, when a layer is referred to as being “between” two layers, it may be the only layer between the two layers, or there may be one or more layers in between.

[0042] In the context of this application, the structure described above the first feature may include embodiments in which the first and second features are formed in direct contact, or embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0043] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0044] like Figure 4 As shown, this embodiment provides a boost device for improving the battery performance of an electrotherapy device. The boost device includes: an inductor 101, a boost diode 102, a first comparator 103, a data acquisition unit 104, a second comparator 105, a driving unit 106, a transistor 107, and a detection resistor 108. The inductor 101 has its first terminal connected to the input voltage and its second terminal connected to the positive terminal of the boost diode 102 and the collector of the transistor 107. The negative terminal of the boost diode 102 is connected to the output voltage. The first input terminal of the first comparator 103 is connected to a first reference voltage. The input terminal of the acquisition unit 104 is connected to the output voltage, and its output terminal is connected to the second input terminal of the first comparator 103. The output terminal of the first comparator 103 is connected to the first input terminal of the driving unit 106. The first input terminal of the second comparator 105 is connected to multiple second reference voltages, and its second input terminal is connected to the emitter of the transistor 107 and the first terminal of the sensing resistor 108. Its output terminal is connected to the second input terminal of the driving unit 106, and the output terminal of the driving unit 106 is connected to the base of the transistor 107. The second terminal of the sensing resistor 108 is grounded. In one embodiment, the boost device further includes an input capacitor 109, with its first terminal connected to the input voltage and its second terminal grounded. In another embodiment, the boost device further includes an output capacitor 110, the first end of which is connected to the output voltage and the second end is grounded.

[0045] In this embodiment, the boost diode 102 is selected as a Schottky diode.

[0046] As an example, the input voltage is generated by a button cell battery, which may have an output voltage of 3V.

[0047] like Figure 4 As shown, in this embodiment, the acquisition unit 104 includes a first voltage divider resistor and a second voltage divider resistor. The first end of the first voltage divider resistor is connected to the output voltage, the second end is connected to the first end of the second voltage divider resistor and the second input end of the first comparator 103, and the second end of the second voltage divider resistor is grounded.

[0048] Specifically, the sensing resistor 108 collects the input current flowing through the transistor 107. When the voltage across the sensing resistor 108 is greater than the second reference voltage, the second comparator 105 enables the driving unit 106 to limit the on-time of the transistor 107, thereby controlling the input current of the transistor 107. For example, the second reference voltage is 2.4mV to 2.5mV; in this embodiment, the second reference voltage is 2.4mV.

[0049] The plurality of second reference voltages include a first voltage, a second voltage, and a third voltage that increase sequentially. In this embodiment, such as Figure 4 As shown, multiple second reference voltages are generated by a reference voltage unit, one end of which is connected to the input voltage, and the other end is connected to the first input terminal of the first comparator 103. When the voltage output by the acquisition unit 104 to the first comparator 103 is lower than the first voltage, the first comparator 103 enables the driving unit 106 to limit the conduction time of the transistor 107, thereby controlling the input current of the transistor 107; when the voltage output by the acquisition unit 104 to the first comparator 103 is higher than the second voltage, the first comparator 103 enables the driving unit 106 to turn off the limiting, so that the transistor 107 conducts, but the detection resistor 108 and the second comparator 105 remain operational; when the voltage output by the acquisition unit 104 to the first comparator 103 is higher than the third voltage, the driving unit 106 stops waveform output, completing the boost. For example, the first voltage is 0.5V to 0.7V, the second voltage is 0.9V to 1.1V, and the third voltage is 1.22V to 1.24V. In this embodiment, the first voltage is 0.6V, the second voltage is 1V, and the third voltage is 1.23V.

[0050] In the above process, when it is necessary to limit the conduction time of the transistor 107, the driving unit 106 limits the conduction time of the transistor 107 to no more than 400 ns (nanoseconds) and the switching frequency to less than 1 MHz.

[0051] This invention uses a method of detecting the current flowing through transistor 107 and feedback control to control the input current, and uses a method of sampling the output voltage to distinguish whether the boost circuit is in the initial power-on state or about to complete the boost, and limits the input current according to the state, thereby effectively controlling the input current of the DC-DC boost circuit and the current of the DC-DC boost circuit at the moment of startup.

[0052] Figure 5 The diagram shows a specific implementation circuit, which includes an inductor L1, a boost diode D1, a first voltage divider resistor R2, a second voltage divider resistor R4, a transistor Q1, a sensing resistor R3, an input capacitor C1, and an output capacitor C2. The first terminal of the inductor is connected to the input voltage VIN, and the second terminal is connected to the positive terminal of the boost diode D1 and the collector of the transistor Q1. The base of the transistor Q1 is connected to the base resistor R1 and the VM-PWM signal, and the emitter is connected to the sensing resistor R3 and the Vin-ADC signal. The second terminal of the sensing resistor R3 is grounded. The negative terminal of the boost diode D1 is connected to the output voltage. The first terminal of the first voltage divider resistor R2 is connected to the output voltage, and the second terminal is connected to the first terminal of the second voltage divider resistor R4 and the VM-ADC signal. The second terminal of the second voltage divider resistor R4 is grounded. The first terminal of the input capacitor C1 is connected to the input voltage, and the second terminal is grounded. The first terminal of the output capacitor C2 is connected to the output voltage, and the second terminal is grounded. The VM-PWM signal is generated by the driving unit, the Vin-ADC signal is fed back to the second comparator and compared with the second reference voltage to generate the first control signal of the driving unit, and the VM-ADC signal is fed back to the first comparator and compared with the first reference voltage to generate the second control signal of the driving unit. Specifically, the control method of the above circuit is as follows: when the boost is started, the voltage of the VM-ADC signal is lower than 0.6V, and the conduction time of transistor Q1 is limited to no more than 400ns (nanoseconds), and the switching frequency is limited to within 1MHz; when the voltage of the VM-ADC signal rises above 1V, the voltage of the Vin-ADC signal needs to be referenced. If the voltage of the Vin-ADC signal is greater than 2.4mV, the conduction time of transistor Q1 is controlled to be no more than 400ns (nanoseconds) until the voltage of the VM-ADC signal reaches 1.23V.

[0053] This embodiment also provides an electrotherapy device, which includes a booster device for improving the battery performance of the electrotherapy device as described in the above embodiment.

[0054] As described above, the booster device of the present invention for improving the battery performance of electrotherapy equipment has the following beneficial effects:

[0055] This invention uses a method of detecting the current flowing through the transistor and feedback control to control the input current, and uses a method of sampling the output voltage to distinguish whether the boost circuit is in the initial power-on state or about to complete the boost, and limits the input current according to the state, thereby effectively controlling the input current of the DC-DC boost circuit and the current of the DC-DC boost circuit at the moment of startup.

[0056] The circuit of this invention is simple and easy to implement; the power consumption of this invention is low and the input current is small, which can extend the output life of button batteries; this invention has a boost effect, which simplifies the boost design of the power supply; this invention can be powered by button batteries, and the output power is limited, which can avoid the harm to the human body caused by excessive current, and has high safety.

[0057] Therefore, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0058] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A booster device for improving the battery performance of electrotherapy equipment, characterized in that, The boost converter includes: an inductor, a boost diode, a first comparator, a data acquisition unit, a second comparator, a driving unit, a transistor, and a sensing resistor; the first terminal of the inductor is connected to the input voltage, the second terminal is connected to the positive terminal of the boost diode and the collector of the transistor, the negative terminal of the boost diode is connected to the output voltage, the first input terminal of the first comparator is connected to a first reference voltage, the input terminal of the data acquisition unit is connected to the output voltage, the output terminal is connected to the second input terminal of the first comparator, the output terminal of the first comparator is connected to the first input terminal of the driving unit, the first input terminal of the second comparator is connected to multiple second reference voltages, the second input terminal is connected to the emitter of the transistor and the first terminal of the sensing resistor, the output terminal is connected to the second input terminal of the driving unit, the output terminal of the driving unit is connected to the base of the transistor, and the second terminal of the sensing resistor is grounded; The acquisition unit includes a first voltage divider resistor and a second voltage divider resistor. The first end of the first voltage divider resistor is connected to the output voltage, the second end is connected to the first end of the second voltage divider resistor and the second input end of the first comparator, and the second end of the second voltage divider resistor is grounded. The sensing resistor collects the input current flowing through the transistor. When the voltage across the sensing resistor is greater than the second reference voltage, the driving unit is enabled by the second comparator to limit the conduction time of the transistor, thereby controlling the input current of the transistor. The plurality of second reference voltages include a first voltage, a second voltage, and a third voltage that increase sequentially. When the voltage output by the acquisition unit to the first comparator is lower than the first voltage, the first comparator enables the driving unit to limit the conduction time of the transistor, thereby controlling the input current of the transistor. When the voltage output by the acquisition unit to the first comparator is higher than the second voltage, the first comparator enables the driving unit to turn off the limit, so that the transistor is turned on, but the detection resistor and the second comparator remain in operation; When the voltage output by the acquisition unit to the first comparator is higher than the third voltage, the driving unit stops waveform output and completes the boost.

2. The booster device for improving battery performance in electrotherapy equipment according to claim 1, characterized in that: The second reference voltage is 2.4mV~2.5mV.

3. The booster device for improving battery performance in electrotherapy equipment according to claim 1, characterized in that: The first voltage is 0.5V~0.7V, the second voltage is 0.9V~1.1V, and the third voltage is 1.22V~1.24V.

4. The booster device for improving battery performance in electrotherapy equipment according to claim 1, characterized in that: The driving unit limits the conduction time of the transistor to no more than 400ns and the switching frequency to below 1MHz.

5. The booster device for improving battery performance in electrotherapy equipment according to claim 1, characterized in that: The boost device also includes an input capacitor, with its first end connected to the input voltage and its second end grounded.

6. The booster device for improving battery performance in electrotherapy equipment according to claim 1, characterized in that: The boost device also includes an output capacitor, with the first end of the output capacitor connected to the output voltage and the second end grounded.

7. The booster device for improving battery performance in electrotherapy equipment according to claim 1, characterized in that: Multiple second reference voltages are generated by a reference voltage unit, one end of which is connected to the input voltage and the other end of which is connected to the first input terminal of the first comparator.

8. An electrotherapy device, characterized in that, The electrotherapy device includes a booster device for improving the battery performance of the electrotherapy device as described in any one of claims 1 to 7.

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