CN204966916U - Can switch USB port connector of charge protection function - Google Patents

Abstract

The utility model discloses a USB port connector capable of switching the charging protection function, which comprises a USB plug end, a connecting wire (30) and an output end (20) which are sequentially connected. The USB plug end has a plastic shell (10), a plastic Fix the metal shielding shell (12) at the opening of the shell, fix the upper cover (2a) and the lower support plate (2b) in the plastic shell and the metal shielding shell, and fix the PCB substrate (4) between the two, the PCB substrate Fix the charging protection circuit (5), the output connection pad (6) and the pin (3) connected to the charging protection circuit and the selection switch (9). The operation handle of the selection switch is controlled by the Through the through hole (11); the protection function of the charging protection circuit can be selected by touching the operating handle, so that the connector can be used as an ordinary data line or as a charging line with charging protection function, which expands the USB port connector. function, bringing more convenience to users.

Description

USB port connector with switchable charging protection function

technical field

The utility model relates to a USB port connector, in particular to a USB port connector with a switching switch capable of starting or stopping the protection function.

Background technique

Nowadays, consumer electronic products are generally powered by lithium-ion batteries. Taking a mobile phone as an example, the basic configuration includes a mobile phone, a charger, and a connection line for charging and data transmission. Let’s talk about the charger first. Now mobile phones are equipped with chargers with constant current (CC) and constant voltage (CV) functions. The standard parameters mainly include input voltage, input current, output voltage, and output current. The output voltage here refers to CV. The common one is 5.1V, the output current is CC, the general standard is 1A, 1.5A, 2.1A, the value here indicates the maximum charging current value that the charger can provide. The common failure of the charger is the quality of the electronic components or the aging of the electronic components, which causes the output voltage to rise, that is, the CV constant voltage function is out of control. When the output voltage is higher than the safe range of the mobile phone, the mobile phone will be damaged. . Besides, on the mobile phone side, the lithium-ion battery itself has a charging protection circuit, one of which is the overcharge protection. The enabling voltage of the overcharge protection is generally between 4.2V--4.35V, depending on the battery. Charging voltage (5V), because the voltage of the lithium battery rises slowly during charging, when the voltage rises to close to the protection voltage (the constant voltage charging stage of the battery), the charging current gradually decreases, and when the charging current is less than a certain value, the lithium battery The battery is basically fully charged. If the charging protection circuit fails and continues to charge, the battery voltage will continue to rise. If the voltage at the charger terminal is higher than the standard voltage, it will easily cause the lithium-ion battery to burn and explode. From the analysis of the many incidents of charging injuries that have occurred, it is very likely to be the above-mentioned reasons, because the reasons for the explosion of lithium-ion batteries are, one is overvoltage charging, and the other is short-circuit causing combustion. Therefore, the industry urgently needs to develop a USB port connector with protection function.

Utility model content

The utility model aims to solve the technical problem that the existing connector has no charging protection function, and proposes a USB port connector which has various protection functions and can activate or stop the protection functions.

In order to solve the above-mentioned technical problems, the technical solution proposed by the utility model is to design a USB port connector capable of switching the charging protection function, which includes a USB plug end connected in sequence, a connecting wire, and an output end. The USB plug end has a plastic shell, Fix the metal shielding shell at the opening of the plastic shell, fix the upper cover and the lower support plate in the plastic shell and the metal shielding shell, and fix the PCB substrate between the two, fix the charging protection circuit on the PCB substrate, and connect the charging protection circuit The pin of the selector switch AN, the operating handle of the selector switch passes through the through hole on the side wall of the plastic shell, and the protection function of the charging protection circuit can be selected by touching the operating handle.

The selector switch AN adopts a toggle switch, which includes a moving contact, a first static contact and a second static contact, and the operating handle drives the shrapnel to make the moving contact and the first moving contact or the second moving contact Connection; the PCB substrate includes a positive wire and a negative wire, the positive wire and the negative wire are coupled to the pins and transmit power to the connecting wire; the charging protection circuit includes an electronic switch connected in series in the positive wire And a control module that controls the on-off of the electronic switch; the moving contact can be connected to the positive pole of the external charger through the pin, the first static contact is directly connected to the positive pole of the connecting wire, and the second static contact is connected through the An electronic switch connects the positive pole in the connecting wire. The control module includes a voltage detection unit connected between the charging positive wire and the negative wire, a current detection unit connected in series in the charging circuit, a processing unit connected to the voltage detection unit and the current detection unit, the processing unit controls the Electronic switch on and off.

The charging protection circuit includes an electronic switch connected in series in the positive wire and a control module for controlling the on-off of the electronic switch; the control module includes a voltage detection unit connected between the charging positive wire and the negative wire, connected in series in the charging circuit The current detection unit in the current detection unit, the processing unit connected to the voltage detection unit and the current detection unit, the processing unit controls the on-off of the electronic switch; a third resistor and a third capacitor are connected in series between the positive lead and the negative lead, and the The selection switch AN adopts a normally open button switch, and the selection switch is connected to both ends of the third capacitor, and the connection point of the third resistor and the third capacitor is connected to the processing unit; when the button switch is pressed, the processing unit receives a low-level trigger signal to protect function switching.

The electronic switch adopts a field effect transistor, and the drain and source of the field effect transistor are connected in series in the charging circuit, and the gate of the field effect transistor is connected to the processing unit.

A fifth resistor and an LED lamp are connected in series between the drain and the gate of the field effect transistor.

Compared with the prior art, the utility model can select whether to activate the protection function through the selection switch. When the protection function is enabled, it can be used as a connector with charging protection; when the protection function is turned off, it can be used as an ordinary data line without being affected by the malfunction of the protection function; the utility model expands the function of the USB port connector, Bring more convenience to users.

Description of drawings

Fig. 1 is the appearance three-dimensional view of the preferred embodiment of the utility model;

Figure 2 is an exploded exploded view of a preferred embodiment of the utility model;

Fig. 3 is a functional block diagram of an embodiment of the utility model;

Fig. 4 is a functional block diagram of another embodiment of the utility model;

Fig. 5 is a circuit diagram of another embodiment of the utility model.

detailed description

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model.

The utility model discloses a USB port connector capable of switching charging protection functions. Referring to FIG. 1 , it includes a USB plug end, a connecting wire 30 and an output end 20 connected in sequence. Among them, the USB plug end is plugged into the charger, and the output end is plugged into electronic products such as mobile phones. Referring to Fig. 2, the USB plug end has a plastic shell 10, a metal shielding shell 12 is fixed at the opening of the plastic shell, an upper cover 2a and a lower supporting plate 2b are fixed in the plastic shell and the metal shielding shell, and a PCB fixed between the two Substrate 4, fixed charging protection circuit 5, output terminal connection pad 6, and pin 3 and selection switch 9 connected to the charging protection circuit on the PCB substrate, pin 3 is used for connecting with an external charger, and the selection switch The operating handle is passed through the through hole 11 on the side wall of the plastic shell, and the user can select the protection function of the charging protection circuit by touching the operating handle, such as selecting whether to enable the protection function. When the protection function is enabled, it can be used as a connector with charging protection; when the protection function is disabled, it can be used as an ordinary data cable without being affected by the malfunction of the protection function. It should be pointed out that the output end can be any standard device plug or socket, such as micro plug, MINI plug, Apple series plug, Type-CUSB3.1 male, Type-CUSB3.1 male, Type-CUSB3.1 male, etc. .

Referring to the functional block diagram of an embodiment shown in Figure 3, the selector switch AN adopts a toggle switch, which includes a moving contact, a first static contact and a second static contact, and the operating handle drives the shrapnel to make the moving The contact is connected to the first movable contact or the second movable contact; the PCB substrate includes a positive lead and a negative lead, which are coupled and connected to the pin 3 and transmit power to the connecting lead 30 The charging protection circuit 5 includes an electronic switch connected in series in the positive wire and a control module for controlling the on-off of the electronic switch; the moving contact can be connected to the positive pole of the external charger through the pin 3, the first static The contact is directly connected to the positive pole of the connecting wire 30, and the second static contact is connected to the positive pole of the connecting wire through an electronic switch. During operation, such as toggling the selector switch AN to connect the moving contact with the first static contact, the charging current passes through the first static contact and directly goes to the connecting wire to charge the electronic product, and the charging protection circuit is disconnected, which has no protective effect. During operation, if the selector switch AN is toggled to connect the moving contact with the second static contact, the positive lead wire is energized, and the charging protection circuit can control the on-off of the electronic switch according to the charging situation, thus playing the role of charging protection.

Fig. 4 is an improvement scheme based on the embodiment shown in Fig. 3, the control module includes a voltage detection unit connected between the charging positive wire and the negative wire, a current detection unit connected in series in the charging circuit, a connection A processing unit of the voltage detection unit and the current detection unit, the processing unit controls the on-off of the electronic switch. It should be pointed out that the electronic switch is connected in series in the charging circuit, that is, it can be connected in series in the positive lead wire VCC (as shown by the solid line in Fig. 2 ), or it can be connected in series in the negative lead wire GND. Wherein the voltage detection unit is used to detect the input voltage, the processing unit receives the measured voltage signal, the processing unit is equipped with a reference voltage circuit and a comparison circuit composed of an operational amplifier, and controls the electronic switch to cut off when the input voltage exceeds the safe voltage range , so that the charging circuit is disconnected, thereby realizing overvoltage protection. The current detection unit is used to detect the charging current, the processing unit receives the measured current signal, the current detection unit is connected in series in the charging circuit, the feedback voltage of the current detection unit is sent to the comparator formed by the operational amplifier in the processing unit The circuit amplifies the feedback signal through the comparison circuit and compares it with the signal of the reference voltage circuit. When an overcurrent or short circuit occurs, the processing unit controls the electronic switch to cut off to disconnect the charging circuit, thereby realizing overcurrent protection. The above circuit without software belongs to the protection object of the utility model.

Referring to the circuit diagram of another embodiment shown in Figure 5, it can be seen from the figure that the charging protection circuit 5 includes an electronic switch connected in series in the positive lead wire and a control module for controlling the on-off of the electronic switch; the control module It includes a voltage detection unit connected between the charging positive wire and the negative wire, a current detection unit connected in series in the charging circuit, a processing unit connected to the voltage detection unit and the current detection unit, and the processing unit controls the on-off of the electronic switch. The third resistor R3 and the third capacitor C3 are connected in series between the positive lead and the negative lead, the selector switch AN adopts a normally open button switch, the selector switch is connected to both ends of the third capacitor, the third resistor and the third capacitor The connection points connect the processing units. The voltage detection unit includes a first resistor R1 and a second resistor R2 connected in series between the charging positive lead wire VCC and the negative lead wire GND, and the connection point of the first and second resistors leads to the processing unit (the processing unit in this embodiment) Send the measured voltage signal to the third pin of U1). The current detection unit includes a ninth resistor R9 connected in series with the negative wire, and the two ends of the ninth resistor send the measured current signal to the 12th and 13th pins of U1 through the eighth resistor R8 and the sixth resistor R6 respectively. When the key switch is pressed, the processing unit receives a low-level trigger signal to switch the protection function. In Figure 5, U1 uses KF8Vseries series chips, which can realize overvoltage protection, overcurrent protection, no-load protection and overcharge protection. In use, the connector is sometimes used as a data cable. During data transmission, the positive and negative wires need to be charged, but the current in the positive and negative wires is extremely small, so it is easy to trigger no-load protection and overcharge protection, resulting in the disconnection of the positive wire and normal data transmission. After power on, the positive wire charges the third capacitor C3 through the third resistor R3, the fourth pin of U1 is at high potential, and the key switch is not pressed, the electronic switch is controlled by the processing unit, and various protection functions are turned on or off. The device is used as a charging line with multiple protection functions; press the key switch AN, the 4th pin of U1 gets a low-level trigger signal, the processing unit controls the electronic switch to conduct, and prohibits other protections except overvoltage protection function, using the USB port connector as a data connection.

In a preferred embodiment, the electronic switch uses a field effect transistor Q1, the drain and source of the field effect transistor are connected in series in the charging circuit, and the gate of the field effect transistor is connected to the processing unit.

A fifth resistor R5 and an LED lamp are connected in series between the drain and the gate of the field effect transistor Q1. When Q1 is turned on, the LED light is on synchronously, indicating that it is charging. When Q1 cuts off, the LED lights go out synchronously, indicating that the charging is over or entering a certain protection state.

The above examples are illustrative only and not limiting. Any equivalent modification or change made without departing from the spirit and scope of the present application shall be included in the scope of the claims of the present application.

Claims (6)

1. one kind can switch the USB port connector of charging protection function, it comprises the USB plug end connected successively, connect wire (30), output (20), it is characterized in that: USB plug end has plastic shell (10), plastic shell opening part fixing metal shielding case (12), at plastic shell and metal shielding internal fixtion upper cover plate (2a) and bottom plate (2b), and the PCB substrate (4) be fixed between the two, PCB substrate is fixed charge protector (5), the contact pin (3) of output line pad (6) and connection charge protector and selector switch (9), the operating grip of described selector switch passes by the through hole (11) on plastic shell sidewall, actuating procedure handle can select the defencive function of charge protector.

2. can switch the USB port connector of charging protection function as claimed in claim 1, it is characterized in that: described selector switch adopts toggle switch, it comprises a moving contact and the first fixed contact and the second fixed contact, and operating grip drives shell fragment that moving contact can be made to be connected with the first moving contact or the second moving contact; Comprise positive wire and cathode conductor in described PCB substrate, positive wire and cathode conductor are of coupled connections with described contact pin (3) and transmit electric power to the described wire (30) that is connected; Described charge protector (5) comprises the electronic switch be serially connected in positive wire and the control module controlling electronic switch break-make; Described moving contact is connected with the positive pole of external charger by described contact pin (3), and the first fixed contact directly connects the positive pole in described connection wire (30), and the second fixed contact connects the positive pole in described connection wire by electronic switch.

3. can switch the USB port connector of charging protection function as claimed in claim 2; it is characterized in that: described control module comprises the processing unit being connected to the voltage detection unit between charging positive wire and cathode conductor, the current sense unit be serially connected in charge circuit, connection voltage detection unit and current sense unit, and processing unit controls the break-make of described electronic switch.

4. can switch the USB port connector of charging protection function as claimed in claim 1, it is characterized in that: described charge protector (5) comprises the electronic switch be serially connected in positive wire and the control module controlling electronic switch break-make; Described control module comprises the processing unit being connected to the voltage detection unit between charging positive wire and cathode conductor, the current sense unit be serially connected in charge circuit, connection voltage detection unit and current sense unit, and processing unit controls the break-make of described electronic switch; Be connected in series the 3rd resistance (R3) and the 3rd electric capacity (C3) between positive wire and cathode conductor, described selector switch (AN) adopts normally open push button switch, and selector switch is attempted by the 3rd electric capacity two ends, the tie point connection handling unit of the 3rd resistance and the 3rd electric capacity; The switching of defencive function is carried out after the switch process unit that pushes button obtains low level triggering signal.

5. the USB port connector that can switch charging protection function as described in claim 3 or 4, is characterized in that: described electronic switch adopts field effect transistor (Q1), and the drain electrode of field effect transistor and source electrode are serially connected in charge circuit, its grid connection handling unit.

6. can switch the USB port connector of charging protection function as claimed in claim 5, it is characterized in that: the drain electrode of described field effect transistor (Q1) be connected in series the 5th resistance (R5) and LED between grid.