Drive circuit of medical vacuum negative pressure machine

Abstract

The utility model relates to a driving circuit of a medical vacuum negative pressure machine, which comprises a main control chip, a lithium battery, a charging management module, a battery voltage detection module, a DC-DC (direct current-direct current) voltage reduction module, a DC-DC voltage boosting module and a voltage stabilizing module, the input end of the main control chip is connected with a negative pressure sensor, and the output end of the main control chip is connected with a vacuum pump driving module. The charging management module controls charging of the lithium battery, the output end of the lithium battery is connected with the DC-DC boosting module, the output end of the DC-DC boosting module is connected with the output end of the DC-DC voltage reduction module, the input end of the DC-DC voltage reduction module is connected with the power adapter, one path of output of the DC-DC voltage reduction module supplies power to the main control chip, and the other path of output of the DC-DC voltage reduction module charges the lithium battery. The battery voltage detection module detects the output voltage of the lithium battery and feeds back the output voltage to the main control chip for electric quantity display, and the charging management module is controlled to work in a constant-voltage charging mode or a constant-current charging mode according to the output voltage of the lithium battery.

Description

Technical Field

[0001] The utility model relates to a drive circuit of a medical vacuum negative pressure machine. Background Art

[0002] Negative pressure wound treatment management, as a closed negative pressure treatment technology, is widely used in the healing treatment of various local tissue wounds to ensure that a negative pressure environment is formed on the surface of the tissue wound, thereby promoting the healing of the wound. A medical vacuum negative pressure machine is commonly used for negative pressure wound treatment. For the convenience of portable use of the medical vacuum negative pressure machine, the power supply mode of the vacuum negative pressure machine in the prior art is a single mode. Some use dry batteries for power supply, and some use rechargeable batteries for power supply. The former method requires frequent replacement of dry batteries, which brings certain inconvenience to use; in the latter method, once the rechargeable battery runs out of power, it can only be fully charged before use. The above power supply methods each have deficiencies in use. Content of the Utility Model

[0003] The utility model discloses a drive circuit of a medical vacuum negative pressure machine, which has both a lithium battery power supply mode and a power adapter connected to the power grid power supply mode, and can realize using the vacuum negative pressure machine while charging.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0005] A drive circuit of a medical vacuum negative pressure machine includes a main control chip, a negative pressure sensor connected to the input end of the main control chip, a vacuum pump drive module connected to the output end of the main control chip, a lithium battery, a charging management module, a battery voltage detection module, a DC-DC buck module, a DC-DC boost module, and a voltage stabilizing module; the charging management module is used to control the charging of the lithium battery. The output end of the lithium battery is connected to the DC-DC boost module, and the output end of the DC-DC boost module is connected to the output end of the DC-DC buck module. The input end of the DC-DC buck module is connected to the power adapter. One output end of the DC-DC buck module is used to supply power to the main control chip after being stabilized by the voltage stabilizing module, and the other output end is used to charge the lithium battery. The battery voltage detection module is used to detect the output voltage of the lithium battery and feedback it to the main control chip for power display. The charging management module controls the charging management module to work in a constant voltage charging mode or a constant current charging mode according to the output voltage of the lithium battery.

[0006] Further, the main control chip adopts an STM32G030K6T6TR microcontroller.

[0007] Further, the DC-DC buck module includes an MP1584 buck chip, and the respective pins of the buck chip are connected as follows: Pin 5 is grounded, Pin 9 is grounded after being connected to resistor R116, Pin 6 is grounded after being connected to resistor R113, Pin 7 is connected to the power adapter, Pin 7 is grounded through capacitor C68, Pin 8 and Pin 1 are connected through capacitor C67, one path of Pin 1 is connected to the cathode of Schottky diode D10, the anode of D10 is grounded, the other path of Pin 1 is connected to inductor L3, the other end of inductor L3 is divided into two paths, one path is grounded through capacitor C69, the other path is connected to resistor R111, the other end of R111 is connected to Pin 4, Pin 4 is grounded through resistor R110, the connection end of R111 and L3 is divided into two paths, one path is connected to the anode of fast recovery rectifier diode D21, the cathode end of D21 is connected to the charging management module for charging the lithium battery, the other path is connected to the anode of Schottky diode D11, the cathode end of D11 is connected to the voltage regulation module, Pin 3 is grounded through two parallel branches, one branch is connected to capacitor C71, the other branch is connected to capacitor C70 and resistor R112, one path of Pin 2 is grounded through resistor R114, and the other path is connected to the power adapter through resistor R125.

[0008] Further, the input end of the DC-DC buck module inputs a 12V voltage through the power adapter, and both output ends of the DC-DC buck module output a 6V voltage.

[0009] Further, the DC-DC boost module includes an FP6293XR-G1 boost chip, and the respective pins of the boost chip are connected as follows: Pin 1 is grounded, Pin 2 is grounded through resistor R107, Pins 3 and 4 are connected and then connected to the output end of the lithium battery, capacitors C58 and C59 are connected in parallel, one end is grounded, and the other end is connected to the input end of Pin 3, Pin 5 is grounded, Pin 9 is grounded through resistor R126, one path of Pin 6 is grounded through resistor R108, the other path is connected to the cathode of Schottky diode D9 through resistor R129, one path of the anode of D9 is connected to Pin 8, the other path is connected to Pin 3 through inductor L2, the cathode end of D9 is connected to the anode of Schottky diode D12, the cathode end of D12 is connected to the output end of the DC-DC buck module, and three capacitors C61, C62, and C63 are connected in parallel between the cathode of D9 and the anode of D12 and then grounded.

[0010] Further, the output voltage of the DC-DC boost module is lower than the output voltage of the DC-DC buck module.

[0011] Further, the charging management module includes a TP4056 charging management chip, and the pins of the charging management chip are connected as follows: Pin 4 is connected to the output terminal of the DC-DC buck module. The connection terminal of Pin 8 is divided into four paths. The first path is connected to Pin 4, the second path is grounded through capacitor C20, the third path is connected to the anode of LED20, the cathode of LED20 is connected to resistor R91, the other end of R91 is connected to Pin 6, the fourth path is connected to the anode of LED19, the cathode of LED19 is connected to resistor R92, and the other end of R92 is connected to Pin 7. Pins 3 and 1 are both grounded, Pin 2 is grounded through resistor RPROG1, and Pin 5 is connected to the lithium battery.

[0012] Further, the main control chip is also connected to the touch screen LCD through a level conversion module, and the level conversion module is used to convert the TTL level to the RS232 level.

[0013] Further, the voltage stabilization module uses an AMS1117 voltage stabilization chip.

[0014] The drive circuit designed by the present utility model has both power supply methods of lithium battery power supply and power adapter connected to the power grid for power supply. When the vacuum negative pressure machine is used in an environment where it is inconvenient to access the power grid, lithium battery power supply can be adopted; when the vacuum negative pressure machine is used in an environment where it is convenient to access the power grid, it can be connected to the power grid through a power adapter. The power adapter outputs 12V voltage to the DC-DC buck module. After the DC-DC buck module reduces the 12V voltage to 6V voltage, it can supply power for the use of the vacuum negative pressure machine while also charging the lithium battery, so as to achieve charging while using. In addition, the present utility model uses a DC-DC boost module to boost the output voltage of the lithium battery of 3.7V to about 6V. In order to give priority to the adapter power supply over the lithium battery when the power adapter is connected, the output voltage of the DC-DC boost module is slightly lower than the output voltage of the DC-DC buck module. Through the design improvement of the power supply circuit of the present utility model, it is more convenient to use the portable vacuum negative pressure machine. Description of the Drawings

[0015] Figure 1 It is the principle block diagram of the drive circuit of the vacuum negative pressure machine in the embodiment;

[0016] Figure 2 It is the pin circuit diagram of the main control chip;

[0017] Figure 3 It is the circuit diagram of the level conversion module;

[0018] Figure 4 It is the circuit diagram of the DC-DC buck module;

[0019] Figure 5 It is the circuit diagram of the DC-DC boost module;

[0020] Figure 6 It is the circuit diagram of the charging management module. Specific implementation manners

[0021] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model.

[0022] This embodiment discloses a drive circuit of a medical vacuum negative pressure machine, which is mainly improved around the single power supply mode of the vacuum negative pressure machine in the prior art. Therefore, this embodiment is provided with two modes: lithium battery power supply and grid power supply. At the same time, considering that the working mode of the vacuum negative pressure machine in the prior art is single and usually cannot be set by itself (such as not having an intermittent mode, or the intermittent mode time cannot be adjusted), therefore, in this embodiment, a touch screen is used to switch and set the working mode, and parameters can be set on the operation interface of the touch screen as needed, which is more convenient to use. The improved drive circuit in this embodiment is as Figure 1 shown, and mainly includes a main control chip, a negative pressure sensor, a vacuum pump drive module, an LCD, a lithium battery, a charging management module, a battery voltage detection module, a DC-DC buck module, a DC-DC boost module, and a voltage stabilization module. The negative pressure sensor is usually arranged at the air inlet of the vacuum pump, used to collect the air pressure change in the negative pressure environment, convert it into a voltage change, and output the voltage change data to feedback to the main control chip. The output end of the main control chip is connected to the vacuum pump drive module to control the start of the vacuum pump motor. The LCD uses serial communication to realize parameter setting on the touch screen, and is connected to the main control chip through a level conversion module. The level conversion module is as Figure 3 shown, and is used to convert TTL level to RS232 level.

[0023] As Figure 2 shown, the main control chip in this embodiment uses an STM32G030K6T6TR microcontroller. The pin 7 of the microcontroller is used as the input signal connection terminal of the negative pressure sensor, the pin 15 of the microcontroller is used as the connection terminal for receiving the output voltage monitoring signal of the lithium battery, and the pin 13 of the microcontroller is used as the connection terminal for driving the vacuum pump motor. The control of the vacuum pump can be regulated by PWM.

[0024] The circuit design of the DC-DC buck module in this embodiment is as Figure 4As shown, the MP1584 buck chip is mainly used in this circuit. The buck chip is used to reduce the 12V voltage input by the power adapter to 6V for output. One path of the output 6V voltage is used to charge the lithium battery, and the other path is reduced to 3.3V through the voltage regulator module to supply power to the main control chip. The connections of each pin of the buck chip in this module circuit are as follows: Pin 5 is grounded, Pin 9 is grounded after connecting resistor R116, Pin 6 is grounded after connecting resistor R113, Pin 7 is used to connect the power adapter, and Pin 7 is also grounded through capacitor C68. Pin 8 is connected to Pin 1 through capacitor C67. One path of Pin 1 is connected to the cathode of Schottky diode D10, and the anode of D10 is grounded. The other path of Pin 1 is connected to inductor L3. The other end of inductor L3 is divided into two paths. One path is grounded through capacitor C69, and the other path is connected to resistor R111. The other end of R111 is connected to Pin 4, and Pin 4 is grounded through resistor R110. The connection end of R111 and L3 is divided into two paths. One path is connected to the anode of fast recovery rectifier diode D21, and the cathode end of D21 outputs 6V voltage to charge the lithium battery. The other path is connected to the anode of Schottky diode D11, and the cathode end of D11 outputs 6V voltage. The 6V voltage is reduced to 3.3V through the voltage regulator module to supply power to the main control chip. The AMS1117 voltage regulator chip is used as the voltage regulator module in this embodiment; Pin 3 is grounded through two parallel branches. One branch is connected to capacitor C71, and the other branch is connected to capacitor C70 and resistor R112. One path of Pin 2 is grounded through resistor R114, and the other path is connected to the power adapter through resistor R125. From Figure 4 it can be seen that the DC-DC buck module can charge the lithium battery and supply power to the system at the same time, enabling charging and using simultaneously. Compared with the power supply circuit in the prior art, it is more convenient to use.

[0025] The circuit design of the DC-DC boost module in this embodiment is as Figure 5As shown, the main boost chip used in this circuit is the FP6293XR-G1. This boost chip is used to boost the 3.7V voltage output by the lithium battery to about 6V for output. The voltage output by the boost chip is reduced to 3.3V through the voltage regulation module and then supplied to the main control chip. The connections of each pin of the boost chip in this module circuit are as follows: Pin 1 is grounded, Pin 2 is grounded through resistor R107, Pin 3 is connected to Pin 4 and then connected to the output terminal of the lithium battery. Capacitors C58 and C59 are connected in parallel, with one end grounded and the other end connected to the input terminal of Pin 3. Pin 5 is grounded, Pin 9 is grounded through resistor R126. One path of Pin 6 is grounded through resistor R108, and the other path is connected to the cathode of Schottky diode D9 through resistor R129. One path of the anode of D9 is connected to Pin 8, and the other path is connected to Pin 3 through inductor L2. The cathode of D9 is connected to the anode of Schottky diode D12. Three capacitors C61, C62, and C63 are connected in parallel between the cathode of D9 and the anode of D12 and then grounded. The cathode of D12 is connected to the output terminal of the DC-DC buck module. In the design of this module, when the user does not connect the power adapter, it can be directly powered by the lithium battery. In order to be able to give priority to using the power adapter to supply power to the system when the power adapter is connected, the voltage output at the cathode of D12 in this module is 0.2V lower than the voltage output by the DC-DC buck module, so that the power grid power supply can be preferentially used when the power adapter is connected.

[0026] The charging management module is mainly used to control the charging of the lithium battery. Cooperating with the voltage detection module that real-time collects the output voltage of the lithium battery, it controls the charging mode of the lithium battery. If the measured output voltage of the lithium battery is lower than the set value, the charging management module will limit the current in the constant current charging mode; if the measured output voltage of the lithium battery reaches the set value, the charging management module will limit the current in the constant voltage charging mode until the lithium battery is fully charged. The circuit of the charging management module is as Figure 6 shown, mainly using the TP4056 charging management chip. The connections of each pin of the charging management chip are as follows: Pin 4 is connected to the output terminal of the DC-DC buck module. The connection terminal of Pin 8 is divided into four paths. The first path is connected to Pin 4, the second path is grounded through capacitor C20, the third path is connected to the anode of LED20, the cathode of LED20 is connected to resistor R91, and the other end of R91 is connected to Pin 6. The fourth path is connected to the anode of LED19, the cathode of LED19 is connected to resistor R92, and the other end of R92 is connected to Pin 7. Pins 3 and 1 are both grounded, Pin 2 is grounded through resistor RPROG1, and Pin 5 is connected to the lithium battery.

[0027] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A drive circuit of a medical vacuum negative pressure machine, characterized in that: It includes a main control chip, a negative pressure sensor connected to the input end of the main control chip, a vacuum pump drive module connected to the output end of the main control chip, a lithium battery, a charging management module, a battery voltage detection module, a DC-DC buck module, a DC-DC boost module, and a voltage stabilization module; the charging management module is used to control the charging of the lithium battery, the output end of the lithium battery is connected to the DC-DC boost module, the output end of the DC-DC boost module is connected to the output end of the DC-DC buck module, the input end of the DC-DC buck module is connected to a power adapter, one output end of the DC-DC buck module supplies power to the main control chip after being stabilized by the voltage stabilization module, and the other output end charges the lithium battery. The battery voltage detection module is used to detect the output voltage of the lithium battery and feedback it to the main control chip for power display. The charging management module controls the charging management module to work in a constant voltage charging mode or a constant current charging mode according to the output voltage of the lithium battery; The DC-DC buck module includes an MP1584 buck chip, and the connections of each pin of the buck chip are as follows: pin 5 is grounded, pin 9 is connected to resistor R116 and then grounded, pin 6 is connected to resistor R113 and then grounded, pin 7 is connected to the power adapter, pin 7 is grounded through capacitor C68, pin 8 and pin 1 are connected by capacitor C67, one path of pin 1 is connected to the cathode of Schottky diode D10, the anode of D10 is grounded, the other path of pin 1 is connected to inductor L3, the other end of inductor L3 is divided into two paths, one path is grounded through capacitor C69, the other path is connected to resistor R111, the other end of R111 is connected to pin 4, pin 4 is grounded through resistor R110, the connection end of R111 and L3 is divided into two paths, one path is connected to the anode of fast recovery rectifier diode D21, the cathode end of D21 is connected to the charging management module to charge the lithium battery, the other path is connected to the anode of Schottky diode D11, the cathode end of D11 is connected to the voltage stabilization module, pin 3 is grounded through two parallel branches, one branch is connected to capacitor C71, the other branch is connected to capacitor C70 and resistor R112, one path of pin 2 is grounded through resistor R114, and the other path is connected to the power adapter through resistor R125.

2. The drive circuit of a medical vacuum negative pressure machine according to claim 1, characterized in that: The main control chip uses an STM32G030K6T6TR microcontroller.

3. The drive circuit of a medical vacuum negative pressure machine according to claim 1, wherein: The input end of the DC-DC buck module inputs a 12V voltage through a power adapter, and both output ends of the DC-DC buck module output a 6V voltage.

4. The drive circuit of a medical vacuum negative pressure machine according to claim 1, characterized in that: The DC-DC boost module includes an FP6293XR-G1 boost chip, and the pins of the boost chip are connected as follows: Pin 1 is grounded, Pin 2 is grounded through resistor R107, Pins 3 and 4 are connected and then connected to the output terminal of the lithium battery. Capacitors C58 and C59 are connected in parallel, with one end grounded and the other end connected to the input terminal of Pin 3. Pin 5 is grounded, Pin 9 is grounded through resistor R126. One path of Pin 6 is grounded through resistor R108, and the other path is connected to the cathode of Schottky diode D9 through resistor R129. One path of the anode of D9 is connected to Pin 8, and the other path is connected to Pin 3 through inductor L2. The cathode terminal of D9 is connected to the anode of Schottky diode D12, and the cathode terminal of D12 is connected to the output terminal of the DC-DC buck module. Three capacitors C61, C62, and C63 are connected in parallel between the cathode of D9 and the anode of D12 and then grounded.

5. The drive circuit of a medical vacuum negative pressure machine according to claim 1, characterized in that: The output voltage of the DC-DC boost module is lower than the output voltage of the DC-DC buck module.

6. The drive circuit of a medical vacuum negative pressure machine according to claim 1, characterized in that: The charging management module includes a TP4056 charging management chip, and the pins of the charging management chip are connected as follows: Pin 4 is connected to the output terminal of the DC-DC buck module. The connection terminal of Pin 8 is divided into four paths. The first path is connected to Pin 4, the second path is grounded through capacitor C20, the third path is connected to the anode of LED20, the cathode of LED20 is connected to resistor R91, and the other end of R91 is connected to Pin 6. The fourth path is connected to the anode of LED19, the cathode of LED19 is connected to resistor R92, and the other end of R92 is connected to Pin 7. Pins 3 and 1 are both grounded, Pin 2 is grounded through resistor RPROG1, and Pin 5 is connected to the lithium battery.

7. The drive circuit of a medical vacuum negative pressure machine according to claim 1, characterized in that: The main control chip is also connected to the touch screen LCD through a level conversion module, and the level conversion module is used to convert TTL level to RS232 level.

8. The drive circuit of a medical vacuum negative pressure machine according to claim 1, characterized in that: The voltage regulation module uses an AMS1117 voltage regulation chip.

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