Lighting constant voltage power supply circuit for smart homes

Abstract

A constant voltage power supply circuit for lighting in smart homes includes: an input module; a two-stage topology module connected to the input module for power factor correction; an output module connected to the two-stage topology module; a dimming module connected to the output module for adjusting the output voltage to achieve brightness adjustment; and a Bluetooth module connected to the dimming module for remote control. The dimming module includes: a main control unit U7, the output terminal of which is connected to the gate of a MOSFET Q3, the source of which is grounded and the drain of which is connected to the output module, so that the main control unit U7 outputs different PWM signals to drive the MOSFET Q7.

Description

Technical Field

[0001] This utility model relates to the field of smart home lighting, and in particular to a constant voltage power supply circuit for lighting applied to smart homes. Background Technology

[0002] Traditional LED driver power supplies mostly employ flyback topologies, which suffer from low efficiency (approximately 80%-85%), insufficient power factor (PF<0.9), and large size, and lack intelligent dimming and remote control functions. In recent years, some solutions have improved accuracy by integrating constant current and constant voltage control chips, but these solutions still fail to address pain points such as Bluetooth communication integration, multiple protection mechanisms, and high-frequency interference suppression. Furthermore, existing solutions lack sufficient optimization in EMI filtering and reliability, resulting in poor power supply stability in complex electromagnetic environments and affecting the lifespan of luminaires. Utility Model Content

[0003] To address the aforementioned issues, this technical solution provides a constant voltage power supply circuit for lighting in smart homes.

[0004] To achieve the above objectives, the technical solution is as follows:

[0005] A constant voltage power supply circuit for lighting used in smart homes, including;

[0006] Input module;

[0007] A two-stage topology module, connected to the input module, is used for power factor correction;

[0008] The output module is connected to the two-level topology module;

[0009] A dimming module, connected to the output module, is used to adjust the output voltage to achieve brightness adjustment;

[0010] A Bluetooth module is connected to the dimming module for remote control.

[0011] The dimming module includes:

[0012] The main control unit U7 has its output terminal connected to the gate of the MOSFET Q3. The source of the MOSFET Q3 is grounded, and its drain is connected to the output module, so that the main control unit U7 outputs different PWM signals to drive the MOSFET Q3.

[0013] In some embodiments, the gate of the MOS transistor Q3 is connected to the main control unit U7 through a resistor R73, and the source of the MOS transistor Q3 is grounded through a resistor R78. The source is also connected to the acquisition terminal of the main control unit U7 through a resistor R72.

[0014] In some embodiments, the two-level topology module includes;

[0015] The main control unit U1 has its first output terminal connected to one side coil of transformer T1A, and its second output terminal connected to one side coil of transformer T2 in sequence through resistor R31, resistor R18, diode D8 and resistor R7.

[0016] In some embodiments, the main control unit U1 is model RED2543.

[0017] In some embodiments, the input module includes a terminal CN1, which is connected to a common-mode inductor L4 and a common-mode inductor L3. A differential-mode inductor L1 is connected between the common-mode inductor L4 and the common-mode inductor L3. A resistor R56 is connected in parallel to the differential-mode inductor L1. A capacitor C1 is connected to both ends of the common-mode inductor L3. A resistor RX1 and a resistor RX2 are connected sequentially to one end of the common-mode inductor L3.

[0018] The beneficial effects of this application are:

[0019] This application integrates a Bluetooth module and utilizes a two-level topology module to achieve high efficiency, with a power factor (PF) ≥ 0.95, meeting the harmonic standard. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0021] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model. Detailed Implementation

[0022] To make the technical problems solved, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0023] Due to the low efficiency of traditional flyback architecture in existing technologies, the power factor (PF) is difficult to meet the mandatory national standard GB17625.1-2022 for harmonics. Secondly, it lacks Bluetooth communication, APP control and dynamic dimming functions, making it unsuitable for smart home scenarios. Furthermore, it only supports basic overcurrent / short circuit protection and does not have graded response designs for overload, abnormal pulse and other scenarios. Finally, high-frequency switching noise is not effectively suppressed, affecting the stability of Bluetooth signal (open communication distance <20 meters).

[0024] Therefore, please refer to Figure 1 As shown, a constant voltage power supply circuit for lighting used in smart homes includes:

[0025] Input module;

[0026] A two-stage topology module, connected to the input module, is used for power factor correction. Based on the RED2543B PPFC+LLC resonant two-stage architecture, it achieves an efficiency of ≥90% and a power factor (PF) of ≥0.95, meeting the harmonic standard GB 17625.1-2022.

[0027] The output module is connected to the two-level topology module;

[0028] A dimming module, connected to the output module, is used to adjust the output voltage to achieve brightness adjustment;

[0029] A Bluetooth module, connected to the dimming module, is used for remote control. It integrates a Bluetooth module and supports APP dimming and multi-mode on / off control.

[0030] The dimming module includes:

[0031] The main control unit U7 has its output terminal connected to the gate of the MOSFET Q3. The source of the MOSFET Q3 is grounded, and its drain is connected to the output module, so that the main control unit U7 outputs different PWM signals to drive the MOSFET Q3.

[0032] Specifically, in the two-stage topology module, the PPFC stage uses the RED2543B to implement active power factor correction, supports wide voltage input (200-240V AC), PF≥0.95, THD<10%; the LLC resonant stage uses the RED2543B to drive the LLC resonant circuit, with isolated output of 12V / 5A, efficiency≥90%, and supports soft switching to reduce EMI.

[0033] The main control unit U7 is an MCU that integrates a 12-bit ADC, PWM and UART. It is responsible for dimming algorithms, Bluetooth communication and protection logic. When the MCU (U7) outputs a PWM wave (frequency 4kHz) to drive the MOSFET (Q3), the duty cycle of 0%-100% corresponds to a brightness of 10%-100%.

[0034] The Bluetooth module U5 integrates 2.4G radio frequency, supports the DALI2 protocol, and is compatible with external remote controls via a 4-pin connector (P1). The MCU communicates with the Bluetooth module via UART, supports OTA firmware upgrades and multi-device pairing, and has a command response time of <50ms. The Bluetooth module (U5) is positioned away from the LLC transformer (T2) to suppress radiation.

[0035] Protection mechanism:

[0036] Overload protection: When the current is >5A, the LED flashes red; when it is >5.5A, the output is shut down and the alarm continues until the current recovers.

[0037] Reset function: Press and hold the reset button for 10 seconds. The MCU will trigger a system reset and start the network configuration process. The indicator light will flash green for 1 minute and then turn off.

[0038] Signal input processing:

[0039] Input signal 1: High level (≥1.7V) turns the light on, low level (≤0.7V) turns the light off.

[0040] Input signal 2: Short pulse (40-100ms) switches the state, long pulse (>500ms) activates dimming, supports hand swipe / touch switch.

[0041] Efficiency test: Full load (12V / 5A) efficiency 91.6%, standby power consumption <0.5W.

[0042] EMI testing: Conducted interference peak value 58dBμV, radiated interference <45dBμV (30MHz-1GHz).

[0043] Reliability testing: Efficiency degradation <2% after high temperature and high humidity aging (85℃, 85%RH / 500h), Bluetooth communication distance ≥30 meters.

[0044] In some embodiments, the gate of the MOS transistor Q3 is connected to the main control unit U7 through a resistor R73, and the source of the MOS transistor Q3 is grounded through a resistor R78. The source is also connected to the acquisition terminal of the main control unit U7 through a resistor R72 for real-time current detection.

[0045] In some embodiments, the two-level topology module includes;

[0046] The main control unit U1 has its first output terminal connected to one side coil of transformer T1A, and its second output terminal connected to one side coil of transformer T2 in sequence through resistor R31, resistor R18, diode D8 and resistor R7.

[0047] In some embodiments, the main control unit U1 is model RED2543.

[0048] In some embodiments, the input module includes a terminal CN1, which is connected to a common-mode inductor L4 and a common-mode inductor L3. A differential-mode inductor L1 is connected between the common-mode inductor L4 and the common-mode inductor L3. A resistor R56 is connected in parallel with the differential-mode inductor L1. A capacitor C1 is connected to both ends of the common-mode inductor L3. A resistor RX1 and a resistor RX2 are connected to one end of the common-mode inductor L3 in sequence to ensure that the conducted interference is <65dBμV.

[0049] The above description is only a preferred embodiment of this application and is not intended to limit the scope of implementation of this application. Any other embodiments whose principles and basic structures are the same as or similar to those of this application are within the protection scope of this application.

Claims

1. A constant voltage power supply circuit for lighting in smart homes, characterized in that, include; Input module; A two-stage topology module, connected to the input module, is used for power factor correction; The output module is connected to the two-level topology module; A dimming module, connected to the output module, is used to adjust the output voltage to achieve brightness adjustment; A Bluetooth module is connected to the dimming module for remote control. The dimming module includes: The main control unit U7 has its output terminal connected to the gate of the MOSFET Q3. The source of the MOSFET Q3 is grounded, and its drain is connected to the output module, so that the main control unit U7 outputs different PWM signals to drive the MOSFET Q3.

2. The lighting constant voltage power supply circuit for smart homes according to claim 1, characterized in that: The gate of the MOS transistor Q3 is connected to the main control unit U7 through resistor R73, and the source of the MOS transistor Q3 is grounded through resistor R78. The source is also connected to the acquisition terminal of the main control unit U7 through resistor R72.

3. The lighting constant voltage power supply circuit for smart homes according to claim 1, characterized in that: The two-level topology module includes: The main control unit U1 has its first output terminal connected to one side coil of transformer T1A, and its second output terminal connected to one side coil of transformer T2 in sequence through resistor R31, resistor R18, diode D8 and resistor R7.

4. The lighting constant voltage power supply circuit for smart homes according to claim 3, characterized in that: The main control unit U1 is model RED2543.

5. The lighting constant voltage power supply circuit for smart homes according to claim 1, characterized in that: The input module includes a terminal CN1, which is connected to a common-mode inductor L4 and a common-mode inductor L3. A differential-mode inductor L1 is connected between the common-mode inductor L4 and the common-mode inductor L3. A resistor R56 is connected in parallel to the differential-mode inductor L1. A capacitor C1 is connected to both ends of the common-mode inductor L3. A resistor RX1 and a resistor RX2 are connected to one end of the common-mode inductor L3 in sequence.

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