A power supply redundancy automatic switching circuit

Abstract

The utility model discloses an embodiment of utilitarian new type discloses a kind of power supply redundancy automatic switching circuit, connect solar panel and battery, including power input module, switching module and charging module;The power input module connects solar panel and switching module, and switching module is connected battery by charging module.The power input module converts alternating current mains into alternating current, and the direct current output of alternating current and solar panel generation;The switching module is integrated after alternating current, adapter voltage and direct current, and whether the corresponding charging power is output according to switch operation control;The charging module charges battery according to the input charging power.Because three kinds of voltage are input, even if adapter and mains are all abnormal and cannot power supply, there is solar energy to continuously provide direct current to battery charging, ensure the normal work of visual doorbell, solve the problem that existing power supply mode exception can influence doorbell normal work.

Description

Technical Field

[0001] This utility model relates to the field of electronic technology, and in particular to a power supply redundancy automatic switching circuit. Background Technology

[0002] Traditional video doorbells most commonly use AC power, directly connected to the household's 220V AC power supply, with an internal transformer stepping down the voltage to 24V before powering the doorbell. While stable and reliable, this requires a power outlet at the installation location. Some use DC power, typically employing a 220VAC or 12VDC power adapter to convert AC to DC for the doorbell, suitable for situations where direct AC power is unavailable. For installations where external power cannot be accessed, battery power becomes the best option. This method avoids complex power wiring installation, but requires high-quality, long-life batteries, which need to be periodically removed for charging or replacement. Simply increasing battery capacity to further improve battery life significantly increases battery cost and size, affecting the appearance. These power supply methods are all independently configured; in the event of a power outage, neither AC nor DC power supply will work; if the battery is low and not charged in time, the video doorbell will not function.

[0003] With increasing awareness of home security and the widespread adoption of the Internet of Things (IoT), users are demanding more doorbells that require minimal maintenance, are environmentally friendly, and offer integrated functionality. Solar-powered doorbells have emerged on the market. These doorbells incorporate a polycrystalline silicon solar panel that converts sunlight into electricity, which is then transmitted to a circuit board via positive and negative contacts. This, combined with a rechargeable battery, provides continuous power, eliminating the need for frequent battery replacements. However, weak sunlight (such as prolonged cloudy days or long periods of shade) can lead to insufficient charging, affecting the doorbell's normal operation.

[0004] Therefore, abnormalities in existing power supply methods can affect the normal operation of the doorbell. Consequently, the existing technology still needs improvement and enhancement. Utility Model Content

[0005] To address the aforementioned technical problems, this utility model provides a power supply redundancy automatic switching circuit to solve the problem that abnormal power supply methods can affect the normal operation of the doorbell.

[0006] This utility model embodiment provides a power supply redundancy automatic switching circuit that connects a solar panel and a battery. It includes a power input module, a switching module, and a charging module. The power input module is connected to the solar panel and the switching module, and the switching module is connected to the battery through the charging module.

[0007] The power input module converts AC mains power into AC power and outputs AC power and DC power generated by the solar panel.

[0008] The switching module integrates AC power, adapter voltage and DC power, and controls whether to output the corresponding charging power according to the switch operation.

[0009] The charging module charges the battery according to the input charging power.

[0010] Optionally, in the power supply redundancy automatic switching circuit, the power input module includes an AC interface, a rectifier bridge, a first inductor, a positive contact, and a negative contact.

[0011] One power pin of the AC interface is connected to the VIN2 pin of the rectifier bridge, and the other power pin of the AC interface is connected to the VIN1 pin of the rectifier bridge. The VOUT+ pin of the rectifier bridge is connected to one end of the first inductor. The other end of the first inductor is the AC power supply terminal, which is connected to the switching module. The VOUT- pin of the rectifier bridge is grounded. The positive contact is connected to the positive terminal of the solar panel and the switching module, and the negative contact is connected to the negative terminal of the solar panel and ground.

[0012] Optionally, in the power supply redundancy automatic switching circuit, the power input module further includes a ferrite bead and a first capacitor. The ferrite bead is connected between a power pin of the AC interface and pin VIN2 of the rectifier bridge, and the first capacitor is connected between the other end of the first inductor and ground.

[0013] Optionally, in the power supply redundancy automatic switching circuit, the switching module includes a DIP switch, a first resistor, a first switching transistor, a second switching transistor, a first diode, a second diode, and a third diode;

[0014] Pin 1 of the DIP switch is connected to the gate of the first switching transistor, pin 2 is grounded, pin 3 is connected to the positive terminal of the battery, the source of the first switching transistor is grounded, the drain of the first switching transistor is connected to one end of the first resistor and the gate of the second switching transistor, and the drain of the second switching transistor is connected to the charging module; the source of the second switching transistor is connected to the other end of the first resistor, the negative terminal of the first diode, the negative terminal of the second diode, and the negative terminal of the third diode; the positive terminal of the first diode is connected to the other end of the first inductor, the negative terminal of the second diode is connected to the adapter voltage, and the negative terminal of the third diode is connected to the positive contact.

[0015] Optionally, in the power supply redundancy automatic switching circuit, the switching module further includes a second resistor, a third resistor, and a fourth resistor; one end of the second resistor is connected to one end of the third resistor and the gate of the first switching transistor, the other end of the second resistor is grounded, the other end of the third resistor is connected to pin 1 of the DIP switch, one end of the fourth resistor is connected to the drain of the first switching transistor, and the other end of the fourth resistor is connected to one end of the first resistor and the gate of the second switching transistor.

[0016] Optionally, in the power supply redundancy automatic switching circuit, the switching module further includes a second capacitor, a fourth diode, and a fifth resistor; one end of the second capacitor is connected to one end of the fourth diode and pin 1 of the DIP switch, the other end of the second capacitor and the other end of the fourth diode are both grounded, and the fifth resistor is connected between pin 3 of the DIP switch and the positive terminal of the battery.

[0017] Optionally, in the power supply redundancy automatic switching circuit, the charging module includes a charging chip, a third capacitor, a second inductor, and a sixth resistor; the VIN pin of the charging chip is connected to one end of the third capacitor and the drain of the second switching transistor, the VGC pin of the charging chip is connected to the other end of the third capacitor, the LX pin of the charging chip is connected to one end of the second inductor, the VS pin of the charging chip is connected to the other end of the second inductor and one end of the sixth resistor, and the other end of the sixth resistor is connected to the positive terminal of the battery.

[0018] Optionally, in the power supply redundancy automatic switching circuit, the charging module further includes a fifth diode, a fourth capacitor, a fifth capacitor, and a seventh resistor; one end of the fifth diode is connected to one end of the fourth capacitor and the VIN pin of the charging chip, the other end of the fifth diode and the other end of the fourth capacitor are both grounded, the fifth capacitor is connected between the other end of the sixth resistor and ground, and the seventh resistor is connected in parallel with the sixth resistor.

[0019] In the technical solution provided by this utility model embodiment, the power supply redundancy automatic switching circuit connects the solar panel and the battery, including a power input module, a switching module, and a charging module. The power input module connects the solar panel and the switching module, and the switching module connects to the battery through the charging module. The power input module converts AC mains power into AC power and outputs the AC power and the DC power generated by the solar panel. The switching module integrates the AC power, adapter voltage, and DC power, and controls whether to output the corresponding charging power according to the switch operation. The charging module charges the battery according to the input charging power. Since all three voltages are input, even if the adapter and mains power are abnormal and cannot supply power, the solar energy can continuously provide DC power to charge the battery, ensuring the normal operation of the video doorbell and solving the problem that abnormal power supply in existing methods will affect the normal operation of the doorbell. Attached Figure Description

[0020] Figure 1 This is a structural block diagram of the power supply redundancy automatic switching circuit in an embodiment of this utility model.

[0021] Figure 2 This is a circuit diagram of the power input module in an embodiment of this utility model.

[0022] Figure 3 This is a circuit diagram of the switching module in an embodiment of the present invention.

[0023] Figure 4This is a circuit diagram of the charging module in an embodiment of the present invention. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments of the present utility model obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0025] It is readily understood that relational terms such as "first" and "second" are used merely to distinguish one entity, operation, or direction from another, without requiring or implying any actual relationship or order between these entities, operations, or directions. The directional terms such as "up," "down," "left," "right," "front," "back," "front," "back," "top," and "bottom," mentioned or possibly used in this specification, are defined relative to the constructions shown in the accompanying drawings. They are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be construed as restrictive. In the following description, various parameters and components are described for embodiments of different constructions. These specific parameters and components are merely examples and do not limit the embodiments of this application.

[0026] Please see Figure 1 This utility model provides a power supply redundancy automatic switching circuit, mainly integrated on a circuit board inside the housing of a video doorbell, but it can also be applied to other solar-powered devices. The power supply redundancy automatic switching circuit connects a solar panel and a rechargeable battery, and includes a power input module 10, a switching module 20, and a charging module 30. The power input module 10 connects the solar panel and the switching module 20, and the switching module 20 connects to the battery through the charging module 30. The power input module 10 converts AC mains power to AC power and outputs the AC power and the DC power generated by the solar panel. The switching module 20 integrates the AC power, adapter voltage, and DC power, and controls whether to output the corresponding charging power according to a switch operation. The charging module 30 charges the battery according to the input charging power. Because all three voltages are input, even if the adapter and mains power are abnormal and unable to supply power, the solar energy continuously provides DC power to charge the battery, ensuring the normal operation of the video doorbell and solving the problem that abnormal power supply methods in existing systems can affect the normal operation of the doorbell.

[0027] like Figure 2As shown, the power input module 10 includes an AC interface J1, a rectifier bridge BD, a first inductor L1, a positive contact U1, and a negative contact U2. One power pin of the AC interface J1 is connected to the VIN2 pin of the rectifier bridge BD, and the other power pin of the AC interface J1 is connected to the VIN1 pin of the rectifier bridge BD. The VOUT+ pin of the rectifier bridge BD is connected to one end of the first inductor L1. The other end of the first inductor L1 is the AC power supply terminal, which is connected to the switching module 20. The VOUT- pin of the rectifier bridge BD is grounded. The positive contact U1 is connected to the positive terminal of the solar panel and the switching module 20, and the negative contact U2 is connected to the negative terminal of the solar panel and ground.

[0028] The AC interface J1 consists of two 2-pin connectors, with pins 1 and 2 interconnected and connected to AC mains power. A rectifier bridge BD (preferably MB6S) rectifies the AC mains power, and the first inductor L1 stores energy before outputting 24V AC +24V. Positive contact U1 and negative contact U2 output DC power SUN generated by the solar panel.

[0029] Preferably, the power input module 10 further includes a ferrite bead RL1 and a first capacitor C1. The ferrite bead RL1 is connected between a power pin of the AC interface J1 and pin VIN2 of the rectifier bridge BD, and the first capacitor C1 is connected between the other end of the first inductor L1 and ground. The ferrite bead RL1 suppresses electromagnetic interference, and the first capacitor C1 is used to filter the output 24V AC power +24V.

[0030] like Figure 3 As shown, the switching module 20 includes a DIP switch U3, a first resistor R1, a first switching transistor Q1, a second switching transistor Q2, a first diode D1, a second diode D2, and a third diode D3. Pin 1 of the DIP switch U3 is connected to the gate of the first switching transistor Q1, pin 2 of the DIP switch U3 is grounded, and pin 3 of the DIP switch U3 is connected to the positive terminal of the battery. The source of the first switching transistor Q1 is grounded, and the drain of the first switching transistor Q1 is connected to one end of the first resistor R1 and the gate of the second switching transistor Q2. The drain of the second switching transistor Q2 is connected to the charging module 30. The source of the second switching transistor Q2 is connected to the other end of the first resistor R1, the negative terminal of the first diode D1, the negative terminal of the second diode D2, and the negative terminal of the third diode D3. The positive terminal of the first diode D1 is connected to the other end of the first inductor L1, the negative terminal of the second diode D2 is connected to the adapter voltage of 5V, and the negative terminal of the third diode is connected to the positive contact U1.

[0031] Wherein, the first switching transistor Q1 is preferably an NMOS transistor (IA1134), and the second switching transistor Q2 is preferably a PMOS transistor (WPM3401); D1 to D3 are preferably Schottky diodes of model MBRS410LT3G. When the DIP switch U3 (SS-22C09-G4) is switched to the position where pins 1 and 3 are connected, it outputs a high-level switching signal ON_OFF_EN; when switched to the position where pins 1 and 2 are connected, it outputs a low-level switching signal ON_OFF_EN.

[0032] When the switching signal ON_OFF_EN is high, Q1 conducts, controlling Q2 to conduct. At this time, the +24V AC power, the 5V adapter voltage (connected to the mains via a 5V power adapter), and the DC power SUN provided by the solar panel are all connected to Q2. Q2 outputs charging power CHAR_PW to the charging module 30. When there is a power outage at the user's home, and both the adapter and mains power are unavailable, the solar panel can still continuously provide charging voltage and current to the battery through the charging module 30, extending battery life. Based on the unidirectional conduction characteristics of D1 to D3, these three voltages will not be transmitted in reverse; they can only be transmitted to the source of Q2. Because three voltages are connected simultaneously, the connection line shared between the source of Q2 and the negative terminals of D1 to D3 needs to be widened during wiring to expand the current path.

[0033] When the switching signal ON_OFF_EN is low, Q1 and Q2 are both turned off, thus stopping battery charging.

[0034] Preferably, the switching module 20 further includes a second resistor R2, a third resistor R3, and a fourth resistor R4; one end of the second resistor R2 is connected to one end of the third resistor R3 and the gate of the first switching transistor Q1, the other end of the second resistor R2 is grounded, the other end of the third resistor R3 is connected to pin 1 of the DIP switch U3, one end of the fourth resistor R4 is connected to the drain of the first switching transistor Q1, and the other end of the fourth resistor R4 is connected to one end of the first resistor R1 and the gate of the second switching transistor Q2.

[0035] R2 is used to pull down the gate of Q1 when there is no switching signal ON_OFF_EN input, to prevent Q1 from being mistakenly turned on. R3 is used for current limiting protection of Q1, and R4 is used for current limiting protection of Q2.

[0036] Preferably, the switching module 20 further includes a second capacitor C2, a fourth diode D4, and a fifth resistor R5; one end of the second capacitor C2 is connected to one end of the fourth diode D4 and pin 1 of the DIP switch U3, the other end of the second capacitor C2 and the other end of the fourth diode D4 are both grounded, and the fifth resistor R5 is connected between pin 3 of the DIP switch U3 and the positive terminal of the battery.

[0037] C2 is used to filter the output switching signal ON_OFF_EN to make it smoother. D4 is an ESD diode for electrostatic protection. R5 is used for current limiting and voltage regulation.

[0038] like Figure 4 As shown, the charging module 30 includes a charging chip U4, a third capacitor C3, a second inductor L2, and a sixth resistor R6. The VIN pin of the charging chip U4 is connected to one end of the third capacitor C3 and the drain of the second switching transistor Q2. The VGC pin of the charging chip U4 is connected to the other end of the third capacitor C3. The LX pin of the charging chip U4 is connected to one end of the second inductor L2. The VS pin of the charging chip U4 is connected to the other end of the second inductor L2 and one end of the sixth resistor R6. The other end of the sixth resistor R6 is connected to the positive terminal of the battery.

[0039] The charging chip U4 is preferably a 3A synchronous buck lithium-ion battery charging chip from the SLM series (such as SLM6600). The charging power supply CHAR_PW is output to charge the battery through the charging chip U4. The charging chip U4 controls the entire charging process.

[0040] The signals input to other pins of the charging chip U4 (corresponding to the corresponding modules) are existing technologies. For example, the CHRG signal on the NCHRG pin indicates the charging status, connected to an external charging indicator light. A low level indicates the indicator light is on, charging is in progress; a high level indicates the charging indicator light is off, charging is complete. The STDBY signal input on the NSTDBY pin controls whether U4 enters standby mode; a low level is valid for standby mode. The CHAR_CE signal input on the NCE pin controls whether U4 is charging; a low level indicates charging, a high level indicates no charging. The NTC signal input on the NTC pin is used for battery temperature detection; a high level indicates the battery temperature is above a threshold, at which point U4 stops working; a low level indicates the battery temperature is normal, and U4's operation is controlled by other signals. This section mainly describes the improved connection relationships; the specific connection methods of these signals are not detailed here.

[0041] Preferably, the charging module 30 further includes a fifth diode D5, a fourth capacitor C4, a fifth capacitor C5, and a seventh resistor R7; one end of the fifth diode D5 is connected to one end of the fourth capacitor C4 and the VIN pin of the charging chip U4, and the other ends of the fifth diode D5 and the fourth capacitor C4 are both grounded; the fifth capacitor C5 is connected between the other end of the sixth resistor R6 and ground; and the seventh resistor R7 is connected in parallel with the sixth resistor R6. D5 is used for electrostatic discharge protection, and C4 and C5 are used to filter the applied voltage.

[0042] In summary, the power supply redundancy automatic switching circuit provided by this utility model can switch between charging and not charging the battery. During charging, it integrates AC power, adapter voltage, and solar DC power for output. Even when the adapter and mains power are unavailable, solar power can continuously provide charging voltage and current to the battery, keeping the battery level consistently high. This eliminates concerns about increased costs while meeting users' daily needs.

[0043] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A power supply redundancy automatic switching circuit, connecting a solar panel and a battery, characterized in that, It includes a power input module, a switching module, and a charging module; the power input module is connected to the solar panel and the switching module, and the switching module is connected to the battery through the charging module; The power input module converts AC mains power into AC power and outputs AC power and DC power generated by the solar panel. The switching module integrates AC power, adapter voltage and DC power, and controls whether to output the corresponding charging power according to the switch operation. The charging module charges the battery according to the input charging power.

2. The power supply redundancy automatic switching circuit according to claim 1, characterized in that, The power input module includes an AC interface, a rectifier bridge, a first inductor, a positive contact, and a negative contact; One power pin of the AC interface is connected to the VIN2 pin of the rectifier bridge, and the other power pin of the AC interface is connected to the VIN1 pin of the rectifier bridge. The VOUT+ pin of the rectifier bridge is connected to one end of the first inductor. The other end of the first inductor is the AC power supply terminal, which is connected to the switching module. The VOUT- pin of the rectifier bridge is grounded. The positive contact is connected to the positive terminal of the solar panel and the switching module, and the negative contact is connected to the negative terminal of the solar panel and ground.

3. The power supply redundancy automatic switching circuit according to claim 2, characterized in that, The power input module also includes a ferrite bead and a first capacitor. The ferrite bead is connected between a power pin of the AC interface and pin VIN2 of the rectifier bridge, and the first capacitor is connected between the other end of the first inductor and ground.

4. The power supply redundancy automatic switching circuit according to claim 2, characterized in that, The switching module includes a DIP switch, a first resistor, a first switching transistor, a second switching transistor, a first diode, a second diode, and a third diode; The first pin of the DIP switch is connected to the gate of the first switching transistor, the second pin of the DIP switch is grounded, the third pin of the DIP switch is connected to the positive terminal of the battery, the source of the first switching transistor is grounded, the drain of the first switching transistor is connected to one end of the first resistor and the gate of the second switching transistor, and the drain of the second switching transistor is connected to the charging module. The source of the second switching transistor is connected to the other end of the first resistor, the cathode of the first diode, the cathode of the second diode, and the cathode of the third diode; the anode of the first diode is connected to the other end of the first inductor, the cathode of the second diode is connected to the adapter voltage, and the cathode of the third diode is connected to the positive contact.

5. The power supply redundancy automatic switching circuit according to claim 4, characterized in that, The switching module further includes a second resistor, a third resistor, and a fourth resistor; one end of the second resistor is connected to one end of the third resistor and the gate of the first switching transistor, the other end of the second resistor is grounded, the other end of the third resistor is connected to pin 1 of the DIP switch, one end of the fourth resistor is connected to the drain of the first switching transistor, and the other end of the fourth resistor is connected to one end of the first resistor and the gate of the second switching transistor.

6. The power supply redundancy automatic switching circuit according to claim 4, characterized in that, The switching module also includes a second capacitor, a fourth diode, and a fifth resistor; one end of the second capacitor is connected to one end of the fourth diode and pin 1 of the DIP switch, and the other end of the second capacitor and the other end of the fourth diode are both grounded; the fifth resistor is connected between pin 3 of the DIP switch and the positive terminal of the battery.

7. The power supply redundancy automatic switching circuit according to claim 4, characterized in that, The charging module includes a charging chip, a third capacitor, a second inductor, and a sixth resistor. The VIN pin of the charging chip is connected to one end of the third capacitor and the drain of the second switching transistor. The VGC pin of the charging chip is connected to the other end of the third capacitor. The LX pin of the charging chip is connected to one end of the second inductor. The VS pin of the charging chip is connected to the other end of the second inductor and one end of the sixth resistor. The other end of the sixth resistor is connected to the positive terminal of the battery.

8. The power supply redundancy automatic switching circuit according to claim 7, characterized in that, The charging module also includes a fifth diode, a fourth capacitor, a fifth capacitor, and a seventh resistor; one end of the fifth diode is connected to one end of the fourth capacitor and the VIN pin of the charging chip, the other end of the fifth diode and the other end of the fourth capacitor are both grounded, the fifth capacitor is connected between the other end of the sixth resistor and ground, and the seventh resistor is connected in parallel with the sixth resistor.

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