Step-down holding circuit of relay, electronic equipment and charging pile

Abstract

According to the step-down holding circuit of the relay, the electronic equipment and the charging pile, the voltage provided by the power supply is converted into the first voltage through the voltage conversion circuit and then is output, so that the relay is driven to be switched on. After the relay is conducted, the control circuit sends a first signal to the feedback circuit, the first signal is used for controlling the feedback circuit to adjust the feedback voltage so that the voltage conversion circuit can convert the voltage provided by the power supply into a second voltage according to the adjusted feedback voltage and then output the second voltage, and the second voltage enables the relay to be kept in a conducted state. The second voltage is smaller than the first voltage. Therefore, the step-down holding circuit can provide the smaller second voltage for the relay after the relay is conducted, so that the relay can be kept in the conducted state, the power supply voltage of the relay can be reduced, the coil power consumption of the relay is further reduced, and the temperature of the relay is reduced by reducing heating of the relay.

Description

Technical Field

[0001] The present application relates to the field of power supply technology, and in particular to a voltage-reducing holding circuit of a relay, an electronic device and a charging pile. Background Art

[0002] The impact of power relays on equipment circuits is mainly power consumption and heat generation problems, because on the one hand, the power relay needs to be driven to close or open, and on the other hand, the relay needs to be kept in the closed or open state. In the prior art, a rated voltage is applied to the relay coil, and the rated voltage drives the power relay to close or open. After the relay is closed, a large current flows through it for a long time, causing the control coil to heat up seriously and the relay power consumption to be large. Summary of the invention

[0003] In view of this, the present application provides a voltage-reducing holding circuit of a relay, an electronic device and a charging pile, which can reduce the voltage output by the voltage conversion circuit after the relay is turned on, so as to keep the relay in the on state and reduce the power consumption and temperature of the relay.

[0004] A first aspect of the present application provides a step-down holding circuit for a relay, the step-down holding circuit comprising a voltage conversion circuit, a feedback circuit and a control circuit, wherein an input end of the voltage conversion circuit is connected to a power supply, and an output end of the voltage conversion circuit is connected to a control coil of the relay; the voltage conversion circuit is used to convert a voltage provided by the power supply into a first voltage and output it, and the first voltage is used to drive the relay to turn on; the feedback circuit is connected to the feedback end of the voltage conversion circuit, and the feedback circuit is used to provide a feedback voltage to the feedback end; the control circuit is connected to the feedback circuit, and the control circuit is used to: when the relay is turned on, send a first signal to the feedback circuit, the first signal is used to control the feedback circuit to adjust the feedback voltage, so that the voltage conversion circuit outputs a second voltage, and the second voltage is used to keep the relay in a conducting state; wherein the second voltage is less than the first voltage.

[0005] In one embodiment, the feedback circuit includes a voltage divider unit and an adjustment unit; the voltage divider unit is connected to the output end and the feedback end of the voltage conversion circuit; the adjustment unit is connected to the connection node between the voltage divider unit and the feedback end, and the adjustment unit is connected to the control circuit; the adjustment unit is used to: when receiving a first signal, adjust the voltage divider resistance of the voltage divider unit to the feedback end to adjust the feedback voltage so that the voltage conversion circuit outputs a second voltage.

[0006] In one embodiment, the voltage dividing unit includes a first resistor, a second resistor and a third resistor, and the regulating unit includes an analog switch unit; the first end of the first resistor is connected to the output end of the voltage conversion circuit, and the second end of the first resistor is connected to the feedback end; the first end of the analog switch unit is connected to the feedback end, the second end of the analog switch unit is connected to the first end of the second resistor, the second end of the second resistor is grounded, the third end of the analog switch unit is connected to the first end of the third resistor, and the second end of the third resistor is grounded; the analog switch unit is connected to the control circuit, and when the analog switch unit receives the first signal, the analog switch unit switches from being conductive between the first end and the second end to being conductive between the first end and the third end; wherein the resistance values ​​of the second resistor and the third resistor are different.

[0007] In one embodiment, the voltage dividing unit includes a first resistor, a second resistor and two third resistors, and the regulating unit includes an analog switch unit; the first end of the first resistor is connected to the output end of the voltage conversion circuit, and the second end of the first resistor is connected to the feedback end; the first end of the analog switch unit is connected to the feedback end, the second end of the analog switch unit is connected to the first end of the second resistor, and the second end of the second resistor is grounded; the two third resistors are connected in series and connected between the third end of the analog switch unit and the ground; the analog switch unit is connected to the control circuit, and when the analog switch unit receives the first signal, the analog switch unit switches from being conductive between the first end and the second end to being conductive between the first end and the third end; wherein the resistance values ​​of the second resistor and the two third resistors are different.

[0008] In one embodiment, the control circuit is further configured to: when it is detected that the relay is turned on, send a first signal to the feedback circuit after a preset time period.

[0009] In one embodiment, the voltage conversion circuit includes a BUCK buck chip, which is used to: when receiving a conduction indication signal, convert the voltage provided by the power supply into a first voltage and output it; and when the feedback circuit adjusts the feedback voltage according to the first signal, output a second voltage according to the adjusted feedback voltage.

[0010] The second aspect of the present application provides an electronic device, including a relay and a step-down holding circuit; when the relay is in a conducting state, the electronic device outputs or receives electric energy through the relay; the step-down holding circuit includes a voltage conversion circuit, a feedback circuit and a control circuit, wherein the input end of the voltage conversion circuit is connected to a power supply, and the output end of the voltage conversion circuit is connected to a control coil of the relay; the voltage conversion circuit is used to convert the voltage provided by the power supply into a first voltage and then output it, and the first voltage is used to drive the relay to conduct; the feedback circuit is connected to the feedback end of the voltage conversion circuit, and the feedback circuit is used to provide a feedback voltage to the feedback end; the control circuit is connected to the feedback circuit, and the control circuit is used to: when the relay is turned on, send a first signal to the feedback circuit, the first signal is used to control the feedback circuit to adjust the feedback voltage, so that the voltage conversion circuit outputs a second voltage, and the second voltage is used to keep the relay in a conducting state; wherein the second voltage is less than the first voltage.

[0011] In one embodiment, the control circuit is further configured to: when it is detected that the relay is turned on, send a first signal to the feedback circuit after a preset time period.

[0012] The third aspect of the present application provides a charging pile, including a relay and a step-down holding circuit. When the relay is in a conducting state, the charging pile outputs electric energy through the relay to charge the device to be charged; the step-down holding circuit includes a voltage conversion circuit, a feedback circuit and a control circuit, wherein the input end of the voltage conversion circuit is connected to a power supply, and the output end of the voltage conversion circuit is connected to a control coil of the relay; the voltage conversion circuit is used to convert the voltage provided by the power supply into a first voltage and then output it, and the first voltage is used to drive the relay to conduct; the feedback circuit is connected to the feedback end of the voltage conversion circuit, and the feedback circuit is used to provide a feedback voltage to the feedback end; the control circuit is connected to the feedback circuit, and the control circuit is used to: when the relay is turned on, send a first signal to the feedback circuit, and the first signal is used to control the feedback circuit to adjust the feedback voltage so that the voltage conversion circuit outputs a second voltage, and the second voltage is used to keep the relay in a conducting state; wherein the second voltage is less than the first voltage.

[0013] Compared with the prior art, this application has at least the following advantages: In an embodiment of the present application, the voltage provided by the power supply is converted into a first voltage by a voltage conversion circuit and then output to drive the relay to turn on. After the relay is turned on, the control circuit sends a first signal to the feedback circuit, and the first signal is used to control the feedback circuit to adjust the feedback voltage, so that the voltage conversion circuit converts the voltage provided by the power supply into a second voltage according to the adjusted feedback voltage and then outputs it, and the second voltage keeps the relay in the on state, and the second voltage is less than the first voltage. Thus, the step-down holding circuit can provide a smaller second voltage to the relay after the relay is turned on, which can not only keep the relay in the on state, but also reduce the power supply voltage of the relay, thereby reducing the power consumption of the coil of the relay, reducing the heat generation of the relay to reduce the temperature of the relay. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic block diagram of a buck holding circuit provided in an embodiment of the present application.

[0015] Figure 2 It is a schematic block diagram of a buck holding circuit provided in another embodiment of the present application.

[0016] Figure 3 It is a circuit structure diagram of the buck holding circuit provided in an embodiment of the present application.

[0017] Figure 4 It is a circuit structure diagram of a step-down holding circuit provided in another embodiment of the present application. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only embodiments of a part of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application. In the absence of conflict, the following different embodiments and features in the embodiments can be combined with each other.

[0019] It should be noted that when a device is said to be "connected to" another device, it may be directly connected to the other device or it may be indirectly connected (with an intervening device).

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0021] The embodiment of the present application proposes a voltage-reducing holding circuit of a relay, an electronic device and a charging pile, which can reduce the voltage output by the voltage conversion circuit after the relay is turned on, so as to keep the relay in the on state and reduce the power consumption and temperature of the relay.

[0022] See also Figure 1 , is a schematic block diagram of a voltage reduction holding circuit 200 of a relay 300 according to an embodiment of the present application. Figure 1 As shown, the buck-hold circuit 200 includes a voltage conversion circuit 210 , a feedback circuit 220 and a control circuit 230 .

[0023] The input end of the voltage conversion circuit 210 is connected to the power supply 100, and the output end of the voltage conversion circuit 210 is connected to the control coil of the relay 300. The voltage conversion circuit 210 is used to convert the voltage provided by the power supply 100 into a first voltage and then output it, and the first voltage is used to drive the relay 300 to conduct. It can be understood that the output end of the voltage conversion circuit 210 is connected to the control coil of the relay 300 to provide a conduction voltage for the relay 300. The power supply 100 can be a photovoltaic component, a battery, etc. Of course, the power supply 100 can also include a photovoltaic component and a DC / DC converter or a battery and a DC / DC converter, etc., and the embodiment of the present application is not limited to this.

[0024] The feedback circuit 220 is connected to the feedback terminal of the voltage conversion circuit 210 , and the feedback circuit 220 is used to provide a feedback voltage to the feedback terminal.

[0025] The control circuit 230 is connected to the feedback circuit 220. When the relay 300 is turned on, the control circuit 230 sends a first signal to the feedback circuit 220, and the first signal is used to control the feedback circuit 220 to adjust the feedback voltage so that the voltage conversion circuit 210 outputs a second voltage, and the second voltage is used to keep the relay 300 in the turned-on state.

[0026] It can be understood that the feedback voltage provided by the feedback circuit 220 before the relay 300 is turned on to when the relay 300 is turned on is different from the feedback voltage adjusted by the feedback circuit 220 according to the first signal. The second voltage is less than the first voltage.

[0027] In the embodiment of the present application, the voltage provided by the power supply 100 is converted into a first voltage by the voltage conversion circuit 210 and then outputted to drive the relay 300 to conduct. After the relay 300 is turned on, the control circuit 230 sends a first signal to the feedback circuit 220, and the first signal is used to control the feedback circuit 220 to adjust the feedback voltage, so that the voltage conversion circuit 210 converts the voltage provided by the power supply 100 into a second voltage according to the adjusted feedback voltage and then outputs it, and the second voltage keeps the relay 300 in the conducting state, and the second voltage is less than the first voltage. Thus, the step-down holding circuit 200 can provide a smaller second voltage to the relay 300 after the relay 300 is turned on, which can not only keep the relay 300 in the conducting state, but also reduce the power supply voltage of the relay 300, thereby reducing the power consumption of the coil of the relay 300, reducing the heating of the relay 300 to reduce the temperature of the relay 300.

[0028] In the embodiment of the present application, the control circuit 230 may include a microcontroller unit (MCU), a control chip, and the like.

[0029] In some embodiments, the control circuit 230 may further send the first signal to the feedback circuit 220 after a preset time period when detecting that the relay 300 is turned on. Thus, it can be ensured that the output voltage of the voltage conversion circuit 210 is reduced from the first voltage to the second voltage only after the relay 300 is turned on, thereby preventing the output voltage of the voltage conversion circuit 210 from being reduced to the second voltage when the relay 300 is not fully turned on, causing the relay 300 to be unable to be turned on.

[0030] The preset duration can be set according to the conduction time required by the relay 300, the time required for the control circuit 230 to detect the conduction of the relay 300, the reaction time of the feedback circuit 220 to receive the first signal, and the time required for the voltage conversion circuit 210 to reduce the output voltage according to the feedback voltage. For example, it can be set to 200~500ms.

[0031] In the embodiment of the present application, the control circuit 230 can confirm whether the relay 300 is turned on by detecting the voltage difference across the relay 300. Alternatively, the relay 300 can send a conduction feedback signal to the control circuit 230 when it is turned on, to indicate to the control circuit 230 that the relay 300 is turned on.

[0032] In some embodiments, Figure 3 and Figure 4 As shown, the voltage conversion circuit 210 may include a BUCK step-down chip U1.

[0033] When receiving the conduction indication signal, the BUCK chip U1 converts the voltage provided by the power supply 100 into a first voltage and outputs it to conduct the relay 300. When the feedback circuit 220 adjusts the feedback voltage according to the first signal, the BUCK chip U1 outputs a second voltage according to the adjusted feedback voltage.

[0034] In this embodiment, the BUCK step-down chip U1 adjusts the output voltage according to the feedback voltage of the feedback terminal FB.

[0035] The conduction indication signal may be sent to the BUCK buck chip U1 by an external device, or may be generated by other modules on the electronic device provided with the buck holding circuit 200 and the relay 300 of the embodiment of the present application and sent to the BUCK buck chip U1. For example, the electronic device is provided with a start switch related to the relay 300, and when the user operates the start switch, the start switch generates a conduction indication signal to the BUCK buck chip U1. Alternatively, other modules of the electronic device may generate a conduction indication signal when receiving relevant signals from an external device, and send the conduction indication signal to the BUCK buck chip U1.

[0036] It is understandable that the first voltage and the second voltage may be determined according to the model of the relay 300. For example, the first voltage may be 12V, 18V, 24V, etc., and the second voltage may be 6V, 6.6V, 7V, etc.

[0037] In a specific example, the first voltage is 12.5V, the second voltage is 6.6V, and the voltage provided by the power supply 100 is 15V. That is, when the BUCK buck chip U1 receives the conduction indication signal, the output end of the BUCK buck chip U1 steps down the 15V voltage provided by the power supply 100 to 12.5V and then outputs it to the control coil of the relay 300, so that the relay 300 is turned on. Then, the feedback voltage of the feedback end FB of the BUCK buck chip U1 is adjusted by the feedback circuit 220, and the BUCK buck chip U1 reduces the voltage of its output end from 12.5V to 6.6V according to the change of the feedback voltage of the feedback end FB, so as to keep the relay 300 turned on.

[0038] In another specific example, the first voltage is 13V and the second voltage is 5.8V. Taking the control coil resistance of the relay 300 as 40Ω as an example, the power of the relay 300 when it is turned on is 13^2 / 40=4.225W. After the relay 300 is turned on, the output voltage of the BUCK buck chip U1 is stepped down to 5.8V, and the buck holding power of the relay 300 is 5.8^2 / 40=0.841V. Therefore, the buck holding power of the relay 300 is one-fourth of the on-power, which effectively reduces the power consumption of the relay 300 and reduces the heating of the relay 300.

[0039] See also Figure 2 In some embodiments, the feedback circuit 220 may include a voltage divider unit 221 and an adjustment unit 222. The voltage divider unit 221 is connected to the output terminal and the feedback terminal FB of the voltage conversion circuit 210. The adjustment unit 222 is connected to the connection node between the voltage divider unit 221 and the feedback terminal FB, and the adjustment unit 222 is connected to the control circuit 230.

[0040] When the first signal is received, the adjusting unit 222 adjusts the voltage dividing resistance of the voltage dividing unit 221 to the feedback terminal FB to adjust the feedback voltage so that the voltage conversion circuit 210 outputs the second voltage.

[0041] Furthermore, if Figure 3 As shown, the voltage dividing unit 221 includes a first resistor R1, a second resistor R2 and a third resistor R3, and the regulating unit 222 includes an analog switch unit SW.

[0042] A first end of the first resistor R1 is connected to the output end of the voltage conversion circuit 210 , and a second end of the first resistor R1 is connected to the feedback end FB.

[0043] The first end of the analog switch unit SW is connected to the feedback end FB, the second end of the analog switch unit SW is connected to the first end of the second resistor R2, the second end of the second resistor R2 is grounded, the third end of the analog switch unit SW is connected to the first end of the third resistor R3, and the second end of the third resistor R3 is grounded. The second resistor R2 and the third resistor R3 have different resistance values.

[0044] The analog switch unit SW is connected to the control circuit 230 . When the analog switch unit SW receives the first signal, the analog switch unit SW switches from being conductive between the first terminal and the second terminal to being conductive between the first terminal and the third terminal.

[0045] In the embodiment of the present application, the analog switch unit SW may be an analog switch chip.

[0046] When the first and second terminals of the analog switch unit SW are turned on, the first resistor R1 and the second resistor R2 divide the voltage, and the feedback voltage received by the feedback terminal FB of the voltage conversion circuit 210 is the voltage across the second resistor R2. When the first and third terminals of the analog switch unit SW are turned on, the first resistor R1 and the third resistor R3 divide the voltage, and the feedback voltage received by the feedback terminal FB of the voltage conversion circuit 210 is the voltage across the third resistor R3. Thus, by switching the end of the analog switch unit SW to be turned on, the switching of the voltage dividing resistor of the feedback terminal FB is realized, thereby changing the feedback voltage of the feedback terminal FB.

[0047] Among them, when the voltage conversion circuit 210 includes a BUCK buck chip U1, there is a certain relationship between the output voltage of the BUCK buck chip U1 and the resistance value of the resistor connected to the feedback terminal FB. For example, Vo=(1+R1 / Ri)*0.6V, Vo is the voltage at the output end of the BUCK buck chip U1, and Ri is the resistance value of the second resistor R2 or the third resistor R3. When the analog switch unit SW is turned on at the first end and the second end, Ri is R2. When the analog switch unit SW is turned on at the first end and the third end, Ri is R3. At this time, in order to ensure that the second voltage is less than the first voltage, it is necessary to set the resistance value of the second resistor R2 to be less than the resistance value of the third resistor R3. Of course, the resistance values ​​of the second resistor R2 and the third resistor R3 in the embodiment of the present application are not limited to this, and can be set according to the properties of the BUCK buck chip U1 actually used.

[0048] In other embodiments, Figure 4 As shown, the voltage dividing unit 221 includes a first resistor R1, a second resistor R2 and two third resistors R3, and the regulating unit 222 includes an analog switch unit SW.

[0049] A first end of the first resistor R1 is connected to the output end of the voltage conversion circuit 210 , and a second end of the first resistor R1 is connected to the feedback end FB.

[0050] The first end of the analog switch unit SW is connected to the feedback end FB, the second end of the analog switch unit SW is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is grounded. The two third resistors R3 are connected in series and connected between the third end of the analog switch unit SW and the ground. The second resistor R2 and the two third resistors R3 have different resistance values.

[0051] The analog switch unit SW is connected to the control circuit 230 . When the analog switch unit SW receives the first signal, the analog switch unit SW switches from being conductive between the first terminal and the second terminal to being conductive between the first terminal and the third terminal.

[0052] In this embodiment, when the first and second ends of the analog switch unit SW are turned on, the first resistor R1 and the second resistor R2 perform voltage division, and the feedback voltage received by the feedback end FB of the voltage conversion circuit 210 is the voltage across the second resistor R2. When the first and third ends of the analog switch unit SW are turned on, the first resistor R1 and the two third resistors R3 perform voltage division, and the feedback voltage received by the feedback end FB of the voltage conversion circuit 210 is the voltage across the two third resistors R3. Thus, by switching the end that is turned on by the analog switch unit SW, the switching of the voltage dividing resistor of the feedback end FB is realized, thereby changing the feedback voltage of the feedback end FB.

[0053] Among them, when the voltage conversion circuit 210 includes a BUCK buck chip U1, there is a certain relationship between the output voltage of the BUCK buck chip U1 and the resistance value of the resistor connected to the feedback terminal FB. For example, Vo=(1+R1 / Ri)*0.6V, Vo is the voltage at the output end of the BUCK buck chip U1, and Ri is the resistance value of the second resistor R2 or the sum of the resistance values ​​of the two third resistors R3. When the analog switch unit SW is turned on at the first end and the second end, Ri is R2. When the analog switch unit SW is turned on at the first end and the third end, Ri is 2*R3. At this time, in order to ensure that the second voltage is less than the first voltage, it is necessary to set the resistance value of the second resistor R2 to be less than the sum of the resistance values ​​of the two third resistors R3. For example, the resistance value of the second resistor R2 and the resistance value of a single third resistor R3 can be the same, so that the sum of the resistance values ​​of the two third resistors R3 is twice the resistance value of the second resistor R2. Of course, in the embodiment of the present application, the resistance values ​​of the second resistor R2 and the third resistor R3 are not limited thereto and can be set according to the properties of the BUCK step-down chip U1 actually used.

[0054] The following Figure 3 and Figure 4 Taking the step-down holding circuit 200 as an example, the specific working process is described as follows: When the BUCK chip U1 receives the conduction indication signal, the BUCK chip U1 converts the voltage provided by the power supply 100 into a first voltage and outputs it to the control coil of the relay 300. At this time, the analog switch unit SW conducts its first and second terminals by default, so that the first resistor R1 and the second resistor R2 divide the voltage.

[0055] After detecting that the relay 300 is turned on, the control circuit 230 sends a first signal to the analog switch unit SW. The analog switch unit SW switches to a state where its first end and its third end are turned on according to the first signal, so that the first resistor R1 and the two third resistors R3 divide the voltage, and the feedback voltage of the feedback terminal FB of the BUCK buck chip U1 changes. The BUCK buck chip U1 reduces its output voltage from the first voltage to the second voltage to achieve voltage reduction and maintenance of the relay 300.

[0056] The embodiment of the present application further provides an electronic device (not shown), comprising a relay 300 and a voltage reduction holding circuit 200. When the relay 300 is in a conducting state, the electronic device outputs or receives electric energy through the relay 300.

[0057] The buck holding circuit 200 includes a voltage conversion circuit 210, a feedback circuit 220 and a control circuit 230. The input end of the voltage conversion circuit 210 is connected to the power supply 100, and the output end of the voltage conversion circuit 210 is connected to the control coil of the relay 300; the voltage conversion circuit 210 is used to convert the voltage provided by the power supply 100 into a first voltage and then output it, and the first voltage is used to drive the relay 300 to conduct. The feedback circuit 220 is connected to the feedback terminal FB of the voltage conversion circuit 210 , and the feedback circuit 220 is used to provide a feedback voltage to the feedback terminal FB.

[0058] The control circuit 230 is connected to the feedback circuit 220. When the relay 300 is turned on, the control circuit 230 sends a first signal to the feedback circuit 220. The first signal is used to control the feedback circuit 220 to adjust the feedback voltage so that the voltage conversion circuit 210 outputs a second voltage. The second voltage is used to keep the relay 300 in the on state. The second voltage is less than the first voltage.

[0059] It can be understood that the beneficial effects and specific implementation methods that can be achieved by the electronic device provided in the embodiment of the present application can refer to the beneficial effects of the corresponding buck-holding circuit 200 provided above, and will not be repeated here. In addition, the circuit structure of the buck-holding circuit 200 in the electronic device provided in the embodiment of the present application is basically the same as the circuit structure of the corresponding buck-holding circuit 200 provided above, and will not be repeated here.

[0060] In some embodiments, the electronic device may include an inverter (not shown), the buck holding circuit 200 is integrated in the inverter, and the inverter may be electrically connected to an external load or a power grid through a relay 300 .

[0061] The embodiment of the present application further provides a charging pile (not shown), including a relay 300 and a buck holding circuit 200. When the relay 300 is in an on state, the charging pile outputs electric energy through the relay 300 to charge the device to be charged.

[0062] It can be understood that the beneficial effects and specific implementation methods that can be achieved by the charging pile provided in the embodiment of the present application can refer to the beneficial effects of the corresponding buck holding circuit 200 provided above, and will not be repeated here. In addition, the circuit structure of the buck holding circuit 200 in the charging pile provided in the embodiment of the present application is basically the same as the circuit structure of the corresponding buck holding circuit 200 provided above, and will not be repeated here.

[0063] It should be noted that the buck holding circuit 200 provided in the embodiment of the present application can be applicable to any electronic device using the relay 300, not limited to a charging pile or an inverter.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application and are not intended to limit it. Although the present application has been described in detail with reference to the preferred embodiments, a person of ordinary skill in the art should understand that the technical solution of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present application.

Claims

1. A voltage-reducing holding circuit for a relay, characterized in that: The step-down holding circuit comprises a voltage conversion circuit, a feedback circuit and a control circuit, wherein: The input end of the voltage conversion circuit is connected to the power supply, and the output end of the voltage conversion circuit is connected to the control coil of the relay; the voltage conversion circuit is used to convert the voltage provided by the power supply into a first voltage and then output it, and the first voltage is used to drive the relay to conduct; The feedback circuit is connected to the feedback end of the voltage conversion circuit, and the feedback circuit is used to provide a feedback voltage to the feedback end; The control circuit is connected to the feedback circuit, and the control circuit is used for: When the relay is turned on, a first signal is sent to the feedback circuit, wherein the first signal is used to control the feedback circuit to adjust the feedback voltage so that the voltage conversion circuit outputs a second voltage, and the second voltage is used to keep the relay in a turned-on state; The second voltage is smaller than the first voltage.

2. The step-down holding circuit according to claim 1, characterized in that: The feedback circuit includes a voltage dividing unit and a regulating unit; The voltage dividing unit is connected to the output terminal of the voltage conversion circuit and the feedback terminal; the regulating unit is connected to the connection node between the voltage dividing unit and the feedback terminal, and the regulating unit is connected to the control circuit; The regulating unit is used for: when receiving the first signal, regulating the voltage dividing resistance of the voltage dividing unit to the feedback end, so as to regulate the feedback voltage, so that the voltage conversion circuit outputs the second voltage.

3. The voltage-reducing holding circuit according to claim 2, characterized in that: The voltage dividing unit includes a first resistor, a second resistor and a third resistor, and the regulating unit includes an analog switch unit; A first end of the first resistor is connected to the output end of the voltage conversion circuit, and a second end of the first resistor is connected to the feedback end; The first end of the analog switch unit is connected to the feedback end, the second end of the analog switch unit is connected to the first end of the second resistor, the second end of the second resistor is grounded, the third end of the analog switch unit is connected to the first end of the third resistor, and the second end of the third resistor is grounded; The analog switch unit is connected to the control circuit. When the analog switch unit receives the first signal, the analog switch unit switches from being conductive between the first end and the second end to being conductive between the first end and the third end. The resistance values ​​of the second resistor and the third resistor are different.

4. The voltage-reducing holding circuit according to claim 2, characterized in that: The voltage dividing unit includes a first resistor, a second resistor and two third resistors, and the regulating unit includes an analog switch unit; A first end of the first resistor is connected to the output end of the voltage conversion circuit, and a second end of the first resistor is connected to the feedback end; The first end of the analog switch unit is connected to the feedback end, the second end of the analog switch unit is connected to the first end of the second resistor, and the second end of the second resistor is grounded; the two third resistors are connected in series and connected between the third end of the analog switch unit and the ground; The analog switch unit is connected to the control circuit. When the analog switch unit receives the first signal, the analog switch unit switches from being conductive between the first end and the second end to being conductive between the first end and the third end; wherein the resistance values ​​of the second resistor and the two third resistors are different.

5. The step-down holding circuit according to any one of claims 1 to 4, characterized in that: The control circuit is also used for: When it is detected that the relay is turned on, the first signal is sent to the feedback circuit after a preset time.

6. The voltage-reducing holding circuit according to claim 1, characterized in that: The voltage conversion circuit includes a BUCK buck chip, and the BUCK buck chip is used for: Upon receiving a conduction indication signal, converting the voltage provided by the power supply into the first voltage and then outputting it; as well as When the feedback circuit adjusts the feedback voltage according to the first signal, the second voltage is output according to the adjusted feedback voltage.

7. An electronic device, characterized in that: It includes a relay and a voltage reduction holding circuit; when the relay is in a conducting state, the electronic device outputs or receives electric energy through the relay; The step-down holding circuit comprises a voltage conversion circuit, a feedback circuit and a control circuit, wherein: The input end of the voltage conversion circuit is connected to the power supply, and the output end of the voltage conversion circuit is connected to the control coil of the relay; the voltage conversion circuit is used to convert the voltage provided by the power supply into a first voltage and then output it, and the first voltage is used to drive the relay to conduct; The feedback circuit is connected to the feedback end of the voltage conversion circuit, and the feedback circuit is used to provide a feedback voltage to the feedback end; The control circuit is connected to the voltage conversion circuit and the feedback circuit, and the control circuit is used for: When the relay is turned on, a first signal is sent to the feedback circuit, wherein the first signal is used to control the feedback circuit to adjust the feedback voltage so that the voltage conversion circuit outputs a second voltage, and the second voltage is used to keep the relay in a turned-on state; The second voltage is smaller than the first voltage.

8. The electronic device according to claim 7, characterized in that: The control circuit is also used for: When it is detected that the relay is turned on, the first signal is sent to the feedback circuit after a preset time.

9. A charging pile, characterized in that: It includes a relay and a step-down holding circuit. When the relay is in the on state, the charging pile outputs electric energy through the relay to charge the device to be charged; The step-down holding circuit comprises a voltage conversion circuit, a feedback circuit and a control circuit, wherein: The input end of the voltage conversion circuit is connected to the power supply, and the output end of the voltage conversion circuit is connected to the control coil of the relay; the voltage conversion circuit is used to convert the voltage provided by the power supply into a first voltage and then output it, and the first voltage is used to drive the relay to conduct; The feedback circuit is connected to the feedback end of the voltage conversion circuit, and the feedback circuit is used to provide a feedback voltage to the feedback end; The control circuit is connected to the voltage conversion circuit and the feedback circuit, and the control circuit is used for: When the relay is turned on, a first signal is sent to the feedback circuit, wherein the first signal is used to control the feedback circuit to adjust the feedback voltage so that the voltage conversion circuit outputs a second voltage, and the second voltage is used to keep the relay in a turned-on state; The second voltage is smaller than the first voltage.

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