Dimmable power supply

Abstract

This application relates to a dimmable power supply, which includes a communication module, a constant current control module, and a digital potentiometer. The digital potentiometer's signal processing changes the current setting of the maximum output current of the constant current control module. A PWM signal is output through the PWM interface of the communication module, allowing the constant current control module to set its current output current based on the duty cycle of the PWM signal. This not only allows for remote and flexible setting of the maximum output current even after potting, but also ensures that in the event of a communication module failure, the constant current control module outputs a high or low level, maintaining the current at the current setting of the maximum output current or zero, without damaging the power supply itself. Furthermore, the resistance of the digital potentiometer remains unchanged due to a communication module failure, thus ensuring a stable maximum output current and preventing damage to the load.

Description

Technical Field

[0001] This application relates to the field of intelligent lighting technology, and in particular to a dimmable power supply. Background Technology

[0002] Traditional adjustable power supplies generally adopt the following two solutions:

[0003] 1) The maximum output current in the circuit is controlled by adjusting the resistance value of an analog potentiometer manually or by other mechanical means. However, this method cannot achieve remote and free setting of the output current because the analog potentiometer is a component installed inside the power supply during manufacturing. After the power supply is potted, the maximum output current cannot be changed, and therefore cannot be reset later.

[0004] 2) Using a Bluetooth module and MCU, the maximum output current of the power supply can be changed by controlling the MCU to output a signal value via Bluetooth. However, this method has two problems: first, the effective range of Bluetooth communication is very short; second, if the MCU malfunctions or restarts, it may cause abnormal internal parameters of the power supply, leading to power supply failure.

[0005] In summary, traditional adjustable power supplies have low safety and cannot freely and remotely set the maximum output current at any time. Utility Model Content

[0006] Therefore, it is necessary to provide a dimmable power supply to address the problems of low safety and inability to freely and remotely set the maximum output current of traditional adjustable power supplies.

[0007] This application provides a dimmable power supply, the dimmable power supply comprising:

[0008] The communication module is equipped with a PWM interface;

[0009] The constant current control module is equipped with a PWM port and an output port, and the PWM interface of the communication module is communicatively connected to the PWM port of the constant current control module.

[0010] A digital potentiometer is disposed between the communication module and the constant current control module, and is used to change the magnitude of the currently set maximum output current at the output port of the constant current control module.

[0011] The PWM interface of the communication module outputs a PWM signal and transmits it to the PWM port of the constant current control module. The duty cycle of the PWM signal is used to set the current output current of the constant current control module. The duty cycle of the PWM signal controlled by the constant current control module is positively correlated with the current output current, and the current output current is less than or equal to the currently set maximum output current.

[0012] Furthermore, the dimmable power supply also includes:

[0013] A first level conversion circuit is disposed between the communication module and the constant current control module, and is used to convert the PWM signal output from the PWM interface of the communication module and then send it to the PWM port of the constant current control module.

[0014] Furthermore, the first level conversion circuit includes:

[0015] First power supply;

[0016] Second power supply;

[0017] The first transistor includes a first base, a first emitter, and a first collector; the first emitter is electrically connected to the PWM interface of the communication module, and the first collector is electrically connected to the PWM port of the constant current control module.

[0018] A first resistor, the first end of which is electrically connected to the first power supply, and the second end of which is electrically connected to the first base of the first transistor;

[0019] The second resistor has its first end electrically connected to the connection link between the first power supply and the first resistor, and its second end electrically connected to the connection link between the PWM interface of the communication module and the first emitter of the first transistor.

[0020] The first capacitor includes a first plate and a second plate. The first plate of the first capacitor is electrically connected to the connection link between the first end of the first resistor and the first end of the second resistor. The second plate of the first capacitor is electrically connected to the connection link between the first resistor and the first base of the first transistor.

[0021] The third resistor has its first end electrically connected to the second power supply, and its second end electrically connected to the connection link between the first collector of the first transistor and the PWM port of the constant current control module.

[0022] Furthermore, the dimmable power supply also includes:

[0023] The second level conversion circuit is located between the communication module and the constant current control module, and is used to convert the first voltage signal output from the INC interface of the communication module and then send it to the INC port of the digital potentiometer.

[0024] Furthermore, the second level conversion circuit includes:

[0025] Third power supply;

[0026] Fourth power supply;

[0027] The second transistor includes a second base, a second emitter, and a second collector; the second emitter is electrically connected to the INC interface of the communication module, and the second collector is electrically connected to the INC port of the digital potentiometer.

[0028] The fourth resistor has its first end electrically connected to the third power supply, and its second end electrically connected to the second base of the second transistor.

[0029] The second capacitor includes a third plate and a fourth plate. The third plate of the second capacitor is electrically connected to the connection link between the third power supply and the first end of the fourth resistor. The fourth plate of the second capacitor is electrically connected to the connection link between the second end of the fourth resistor and the second base of the second transistor.

[0030] The fifth resistor has its first end electrically connected to the fourth power supply, and its second end electrically connected to the connection link between the second collector of the second transistor and the INC port of the digital potentiometer.

[0031] Furthermore, the dimmable power supply also includes:

[0032] The third level conversion circuit is located between the communication module and the constant current control module, and is used to convert the level of the second voltage signal output from the U / D interface of the communication module and then send it to the U / D port of the digital potentiometer.

[0033] Furthermore, the third level conversion circuit includes:

[0034] Fifth power supply;

[0035] Sixth power supply;

[0036] The third transistor includes a third base, a third emitter, and a third collector; the third emitter is electrically connected to the U / D interface of the communication module, and the third collector is electrically connected to the U / D port of the digital potentiometer.

[0037] The sixth resistor, the second end of which is electrically connected to the third base of the third transistor;

[0038] The third capacitor includes a fifth plate and a sixth plate. The fifth plate of the third capacitor is electrically connected to the fifth power supply, and the sixth plate of the third capacitor is electrically connected to the connection link between the second terminal of the sixth resistor and the third base of the third transistor. The first terminal of the sixth resistor is electrically connected to the connection link between the fifth power supply and the fifth plate of the third capacitor.

[0039] The seventh resistor has its first end electrically connected to the sixth power supply, and its second end electrically connected to the connection link between the third collector of the third transistor and the U / D port of the digital potentiometer.

[0040] Furthermore, the constant current control module is provided with an RWB interface, and the RWB interface of the constant current control module is communicatively connected to the RWB port of the digital potentiometer.

[0041] This application relates to a dimmable power supply. The power supply incorporates a communication module, a constant current control module, and a digital potentiometer. The digital potentiometer is positioned between the communication module and the constant current control module. Signal processing by the digital potentiometer alters the current setting of the maximum output current at the output port of the constant current control module. A PWM signal is output through the PWM interface of the communication module, allowing the constant current control module to set its output current based on the duty cycle of the PWM signal. This design not only allows for remote dimming commands from a host computer to freely adjust the maximum output current even after potting, but also prevents damage to the power supply itself in the event of a communication module failure. The constant current control module outputs a high or low level, maintaining the current at the current setting of the maximum output current or zero. Furthermore, the resistance of the digital potentiometer remains unchanged despite the communication module failure, ensuring a stable maximum output current. This prevents excessive output current even when the constant current control module outputs a high level, thus avoiding damage to the load. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of a dimmable power supply provided in an embodiment of this application.

[0043] Figure 2 This is a schematic diagram showing the connection relationship between a dimmable power supply and a host computer provided in an embodiment of this application.

[0044] Figure 3 This is a schematic diagram of the structure of a dimmable power supply provided in an embodiment of this application.

[0045] Figure label:

[0046] 10 - Dimmable power supply; 100 - Communication module; 110 - PWM interface; 120 - INC interface;

[0047] 130 - U / D interface; 200 - Constant current control module; 210 - PWM port; 220 - Output port;

[0048] 230 - RWB interface; 300 - First level conversion circuit; 310 - First power supply;

[0049] 320 - Second power supply; 330 - First transistor; 331 - First base;

[0050] 332 - First emitter; 333 - First collector; 340 - First resistor;

[0051] 341 - First terminal of the first resistor; 342 - Second terminal of the first resistor; 350 - Second resistor;

[0052] 351 - First terminal of the second resistor; 352 - Second terminal of the second resistor; 360 - First capacitor;

[0053] 361 - First plate; 362 - Second plate; 370 - Third resistor;

[0054] 371 - First terminal of the third resistor; 372 - Second terminal of the third resistor; 400 - Digital potentiometer;

[0055] 410-INC port; 420-U / D port; 430-RWB port; 440-GND port;

[0056] 450-VCC port; 460-CS port; 470-RH port; 480-RL port;

[0057] 500 - Second level conversion circuit; 510 - Third power supply; 520 - Fourth power supply;

[0058] 530 - Second transistor; 531 - Second base; 532 - Second emitter; 533 - Second collector;

[0059] 540 - Fourth resistor; 541 - First terminal of the fourth resistor; 542 - Second terminal of the fourth resistor;

[0060] 550 - Second capacitor; 551 - Third plate; 552 - Fourth plate; 560 - Fifth resistor;

[0061] 561 - First terminal of the fifth resistor; 562 - Second terminal of the fifth resistor; 600 - Third level conversion circuit;

[0062] 610 - Fifth power supply; 620 - Sixth power supply; 630 - Third transistor; 631 - Third base;

[0063] 632 - Third emitter; 633 - Third collector; 640 - Sixth resistor;

[0064] 641 - First terminal of the sixth resistor; 642 - Second terminal of the sixth resistor; 650 - Third capacitor;

[0065] 651 - Fifth plate; 652 - Sixth plate; 660 - Seventh resistor; 661 - First terminal of the seventh resistor;

[0066] 662 - The second terminal of the seventh resistor; 670 - The seventh power supply; 20 - The host computer. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0068] This application provides a dimmable power supply 10. It should be noted that the dimmable power supply 10 provided in this application is connected to a load. The load can be a lamp, and the dimmable power supply provided in this application is used to dim the lamp.

[0069] like Figure 1 As shown, in one embodiment of this application, the dimmable power supply 10 includes a communication module 100 and a constant current control module 200. Figure 3 As shown, the communication module 100 is provided with a PWM interface 110. The constant current control module 200 is provided with a PWM port 210 and an output port 220. The PWM interface 110 of the communication module 100 and the PWM port 210 are communicatively connected.

[0070] The adjustable light power supply 10 also includes a digital potentiometer 400. The digital potentiometer 400 is disposed between the communication module 100 and the constant current control module 200. The digital potentiometer 400 is used to change the magnitude of the currently set maximum output current at the output port of the constant current control module 200.

[0071] The PWM interface 110 of the communication module 100 outputs a PWM signal and transmits it to the PWM port 210 of the constant current control module 200. The duty cycle of the PWM signal is used to set the magnitude of the current output current output by the output port 220 of the constant current control module 200. The duty cycle of the PWM signal controlled by the constant current control module 200 is positively correlated with the magnitude of the current output current, and the current output current is less than or equal to the currently set maximum output current.

[0072] Specifically, the digital potentiometer 400 is widely used in applications requiring precise resistance adjustment, such as fine-tuning and scaling analog signals, and voltage regulation in DC-DC converters. They can be adjusted via CPU digital communication without requiring a complex circuit environment.

[0073] The digital potentiometer 400 is constructed using a series of resistors connected by a switch array. The digital potentiometer 400 receives signals from a microcontroller or other control unit and changes its resistance value via a serial bus (such as I2C, SPI, etc.). In this application, it receives two voltage signals from the communication module 100 to change the resistance value. The internal structure of the digital potentiometer 400 includes an up / down counter, a decoding circuit, a save and restore control circuit, and non-volatile memory, etc. These internal structures are not the focus of this application and are therefore not shown in the accompanying drawings.

[0074] like Figure 2 As shown, the entire dimmable power supply 10 is connected to an external host computer 20 via a communication module 100. The host computer 20 and the communication module 100 are connected via a wireless network, which has a much longer communication distance than Bluetooth. The communication module 100 receives dimming commands from the host computer 20 and outputs two voltage signals to a digital potentiometer 400 based on the dimming commands. After processing by the digital potentiometer 400, it outputs a voltage signal to the constant current control module 200. The constant current control module 200 sets the maximum current value output by the constant current control module 200 based on the variable resistor value output by the digital potentiometer 400.

[0075] While receiving the dimming command sent by the host computer 20, the communication module 100, in addition to outputting two voltage signals to the digital potentiometer 400, also outputs a PWM signal to the constant current control module 200 according to the dimming command. After receiving the PWM signal, the constant current control module 200 analyzes the PWM signal to obtain the duty cycle of the PWM signal.

[0076] PWM duty cycle refers to the ratio of the high-level time to the total cycle time in a PWM signal, usually expressed as a percentage. The formula for calculating the duty cycle is: Duty cycle = High-level time / Total cycle time × 100%. The constant current control module 200 controls the magnitude of the current output current by using the duty cycle of the PWM signal.

[0077] The PWM signal involved in this application is implemented through a dedicated PWM controller (e.g., a PWM chip) or a digital signal processor (DSP), and does not rely on a computer program to implement specific control functions. By configuring the parameters of the PWM controller or DSP and starting the PWM controller, it can output PWM signals according to the configured parameters.

[0078] Optionally, the duty cycle of the PWM signal controlled by the constant current control module 200 is positively correlated with the magnitude of the current output current. That is, the larger the duty cycle of the PWM signal, the larger the value of the current output current output by the constant current control module 200, and the current output current is less than or equal to the currently set maximum output current.

[0079] Optionally, in one embodiment, the constant current control module 200 controls the magnitude of its current output current to be equal to the magnitude of the currently set maximum output current multiplied by the duty cycle of the PWM signal.

[0080] This embodiment involves two distinct concepts: the currently set maximum output current and the current output current. To clarify these two concepts, a third concept needs to be introduced: the upper limit of the power supply output current.

[0081] The upper limit of the power supply output current is the maximum output current capability that the internal components of the power supply can achieve after the power supply is designed. After potting, the upper limit of the power supply output current cannot be changed. This application introduces a digital potentiometer 400 to adjust the currently set maximum output current. The currently set maximum output current is always less than the upper limit of the power supply output current because the digital potentiometer 400 has a large resistance, which can limit the output current of the constant current control module 200.

[0082] For example, if the upper limit of the power supply output current is set to 4A, the current maximum output current can be changed by adjusting the resistance of the digital potentiometer 400. When the digital potentiometer 400 is slid to the maximum resistance of 10KΩ, the corresponding current maximum output current is 2A. When the digital potentiometer 400 is slid to the minimum resistance of 0KΩ, the corresponding current maximum output current is 0.5A. Therefore, this application can change the resistance of the digital potentiometer 400 so that the current maximum output current can be set arbitrarily between 0.5A and 2A, thus achieving the purpose of freely and remotely setting the maximum output current of the power supply at any time.

[0083] The currently set maximum output current is not the power supply's operating current. The current output current ultimately output by the constant current control module 200 is the power supply's operating current, and this setting is achieved through PWM signal control. The magnitude of the current output current is equal to the magnitude of the currently set maximum output current multiplied by the duty cycle of the PWM signal.

[0084] For example, if the duty cycle of the PWM signal is 80%, the resistance of the digital potentiometer 400 is at its maximum value, and the current maximum output current is set to 2000mA, then the current output current controlled by the constant current control module 200 is equal to 2000mA × 80% = 1600mA.

[0085] Therefore, the dimmable power supply 10 provided in this application uses PWM signal control and the resistance change control of digital potentiometer 400 to collaboratively complete the setting of the current maximum output current and the current output current.

[0086] In this embodiment, this application relates to a dimmable power supply. The power supply includes a communication module 100, a constant current control module 200, and a digital potentiometer 400. The digital potentiometer 400 is positioned between the communication module 100 and the constant current control module 200. Signal processing by the digital potentiometer 400 changes the current maximum output current of the constant current control module 200's output port. A PWM signal is output through the PWM interface 110 of the communication module 100, allowing the constant current control module 200 to set the current output current of its output port 220 based on the duty cycle of the PWM signal. This not only allows the power supply to maintain its maximum output current at any time after potting, via a remote host computer 20, but also ensures that in the event of a communication module failure, the constant current control module 200 outputs a high or low level, with the current output current being the current maximum or zero, preventing damage to the power supply itself. Furthermore, the resistance value of the digital potentiometer 400 will not change due to a malfunction in the communication module 100, but will remain unchanged. Therefore, the current maximum output current will remain stable, ensuring that even when the constant current control module 200 outputs a high level, its current output current will not become excessive, thus preventing damage to the load. The load can be a lighting fixture.

[0087] like Figure 3As shown, in one embodiment of this application, the dimmable power supply 10 further includes a first level conversion circuit 300. The first level conversion circuit 300 is disposed between the communication module 100 and the constant current control module 200. The first level conversion circuit 300 is used to convert the level of the PWM signal output from the PWM interface 110 of the communication module 100 and then send it to the PWM port 210 of the constant current control module 200.

[0088] Specifically, since a PWM signal is a discrete-time signal with discrete pulse widths and fixed pulse amplitudes, the constant current control module 200 may not be able to recognize it correctly. Therefore, the first level conversion circuit 300 can convert the level of the PWM signal output by the communication module 100 to output a level signal that the constant current control module 200 can recognize. That is, the PWM interface 110 of the communication module 100 outputs a PWM signal, and the PWM port 210 of the constant current control module 200 also receives a PWM signal. They are the same type of signal, but their effective voltage values ​​are different, so the first level conversion circuit 300 is needed to convert the levels.

[0089] The level conversion involved in this application is not implemented through a computer program, but through hardware circuitry. The specific electronic components included in the first level conversion circuit 300 will be detailed later.

[0090] In this embodiment, by setting the first level conversion circuit 300, the PWM signal output by the communication module 100 can be level converted to output a level signal that the constant current control module 200 can normally recognize, thereby realizing the setting of the maximum output current of the dimmable power supply 10.

[0091] Please continue reading. Figure 3 In one embodiment of this application, the first level conversion circuit 300 includes a first power supply 310, a second power supply 320, a first transistor 330, a first resistor 340, a second resistor 350, a first capacitor 360, and a third resistor 370.

[0092] The first transistor 330 includes a first base 331, a first emitter 332, and a first collector 333.

[0093] The first emitter 332 is electrically connected to the PWM interface 110 of the communication module 100, and the first collector 333 is electrically connected to the PWM port 210 of the constant current control module 200. The first terminal 341 of the first resistor 340 is electrically connected to the first power supply 310, and the second terminal 342 of the first resistor 340 is electrically connected to the first base 331 of the first transistor 330. The first terminal 351 of the second resistor 350 is electrically connected to the connection link between the first power supply 310 and the first resistor 340, and the second terminal 352 of the second resistor 350 is electrically connected to the connection link between the PWM interface 110 of the communication module 100 and the first emitter 332 of the first transistor 330.

[0094] The first capacitor 360 includes a first plate 361 and a second plate 362. The first plate 361 of the first capacitor 360 is electrically connected to the connection link between the first terminal 341 of the first resistor 340 and the first terminal 351 of the second resistor 350. The second plate 362 of the first capacitor 360 is electrically connected to the connection link between the first resistor 340 and the first base 331 of the first transistor 330. The first terminal 371 of the third resistor 370 is electrically connected to the second power supply 320. The second terminal 372 of the third resistor 370 is electrically connected to the connection link between the first collector 333 of the first transistor 330 and the PWM port 210 of the constant current control module 200.

[0095] Specifically, this embodiment provides a detailed configuration scheme for the first level conversion circuit 300.

[0096] Please continue reading. Figure 3 In one embodiment of this application, the dimmable power supply 10 further includes a second level conversion circuit 500.

[0097] The second level conversion circuit 500 is disposed between the communication module 100 and the constant current control module 200. The second level conversion circuit 500 is used to convert the level of the first voltage signal output from the INC interface 120 of the communication module 100 and then send it to the INC port 410 of the digital potentiometer 400.

[0098] Specifically, the INC port 410 of the digital potentiometer 400 is an adjustment step port, used to adjust the number of steps the taps of the digital potentiometer 400 can be adjusted up or down. Specifically, the INC port 410 transmits a high-level signal or a low-level signal, and when used in conjunction with the U / D port 420 and the CS port 460, it can control the increase or decrease of the resistance value of the digital potentiometer 400.

[0099] The GND port 440 of the digital potentiometer 400 is grounded.

[0100] The level conversion involved in this application is not implemented through a computer program, but through hardware circuitry. The specific electronic components included in the second level conversion circuit 500 will be detailed later.

[0101] In this embodiment, because the voltage level of the voltage signal output by the communication module 100 is different from the voltage signal level that the digital potentiometer 400 can receive and correctly identify, a second level conversion circuit 500 is set to convert the first voltage signal output by the INC interface 120 of the communication module 100 to generate a control signal and send it to the INC port 410 of the digital potentiometer 400, thereby enabling the communication module 100 to identify the first voltage signal output by the communication module 100.

[0102] Please continue reading. Figure 3 In one embodiment of this application, the second level conversion circuit 500 includes a third power supply 510, a fourth power supply 520, a second transistor 530, a fourth resistor 540, a second capacitor 550, and a fifth resistor 560.

[0103] The second transistor 530 includes a second base 531, a second emitter 532, and a second collector 533. The second emitter 532 is electrically connected to the INC interface 120 of the communication module 100. The second collector 533 is electrically connected to the INC port 410 of the digital potentiometer 400. The first terminal 541 of the fourth resistor 540 is electrically connected to the third power supply 510. The second terminal 542 of the fourth resistor 540 is electrically connected to the second base 531 of the second transistor 530.

[0104] The second capacitor 550 includes a third plate 551 and a fourth plate 552. The third plate 551 of the second capacitor 550 is electrically connected to the connection link between the third power supply 510 and the first terminal 541 of the fourth resistor 540. The fourth plate 552 of the second capacitor 550 is electrically connected to the connection link between the second terminal 542 of the fourth resistor 540 and the second base 531 of the second transistor 530. The first terminal 561 of the fifth resistor 560 is electrically connected to the fourth power supply 520. The second terminal 562 of the fifth resistor 560 is electrically connected to the connection link between the second collector 533 of the second transistor 530 and the INC port 410 of the digital potentiometer 400.

[0105] Specifically, this embodiment provides a detailed configuration scheme for an optional second level conversion circuit 500.

[0106] Please continue reading. Figure 3 In one embodiment of this application, the dimmable power supply 10 further includes a third level conversion circuit 600. The third level conversion circuit 600 is disposed between the communication module 100 and the constant current control module 200. The third level conversion circuit 600 is used to convert the level of the second voltage signal output from the U / D interface 130 of the communication module 100 and then transmit it to the U / D port 420 of the digital potentiometer 400.

[0107] Specifically, the level conversion involved in this application is not implemented through a computer program, but through hardware circuitry. The specific electronic components included in the third level conversion circuit 600 will be detailed later.

[0108] The U / D port 420 (up / down port) of the digital potentiometer 400 is also used to control the increase or decrease of the resistance value of the digital potentiometer 400. U / D port 420 works in conjunction with INC port 410. U / D port 420 transmits a pulse signal, a square wave signal. U / D port 420 is the control port for adjusting the taps of the digital potentiometer 400 up and down, while INC port 410 is the port for adjusting the number of steps. To adjust the digital potentiometer 400 tap by 2 steps, U / D port 420 is at a high level, and then INC port 410 changes between high and low levels twice, thus completing the adjustment of the digital potentiometer 400 tap by 2 steps.

[0109] When it is necessary to adjust the 400 tap of the digital potentiometer down by 3 steps, the U / D port 420 is at a low level, and then the INC port 410 changes between high and low levels 3 times, thus completing the adjustment of the 400 tap of the digital potentiometer down by 3 steps.

[0110] In this implementation, because the voltage level of the voltage signal output by the communication module 100 is different from the voltage signal level that the digital potentiometer 400 can receive and correctly identify, a third level conversion circuit 600 is used to convert the second voltage signal output from the U / D interface 130 of the communication module 100 into a pulse signal, which is then sent to the U / D port 420 of the digital potentiometer 400. This allows the communication module 100 to identify the second voltage signal output by the communication module 100. The voltage of the second voltage signal after level conversion is the voltage supplied to the digital potentiometer 400 chip itself, that is, the operating voltage of the digital potentiometer 400. For example, if the operating voltage of the digital potentiometer 400 is 3.3V, then the voltage of the pulse signal generated by the third level conversion circuit 600 after level conversion of the second voltage signal output from the U / D interface 130 of the communication module 100 is at most 3.3V.

[0111] Please continue reading. Figure 3In one embodiment of this application, the third level conversion circuit 600 includes a fifth power supply 610, a sixth power supply 620, a third transistor 630, a sixth resistor 640, a third capacitor 650, and a seventh resistor 660.

[0112] The third transistor 630 includes a third base 631, a third emitter 632, and a third collector 633. The third emitter 632 is electrically connected to the U / D interface 130 of the communication module 100. The third collector 633 is electrically connected to the U / D port 420 of the digital potentiometer 400. The second terminal 642 of the sixth resistor 640 is electrically connected to the third base 631 of the third transistor 630.

[0113] The third capacitor 650 includes a fifth plate 651 and a sixth plate 652. The fifth plate 651 of the third capacitor 650 is electrically connected to the fifth power supply 610. The sixth plate 652 of the third capacitor 650 is electrically connected to the connection link between the second terminal 642 of the sixth resistor 640 and the third base 631 of the third transistor 630. The first terminal 641 of the sixth resistor 640 is electrically connected to the connection link between the fifth power supply 610 and the fifth plate 651 of the third capacitor 650.

[0114] The first terminal 661 of the seventh resistor 660 is electrically connected to the sixth power supply 620. The second terminal 662 of the seventh resistor 660 is electrically connected to the connection link between the third collector 633 of the third transistor 630 and the U / D port 420 of the digital potentiometer 400.

[0115] Specifically, this embodiment provides a detailed configuration scheme for an optional third level conversion circuit 600.

[0116] Please continue reading. Figure 3 In one embodiment of this application, the constant current control module 200 is provided with an RWB interface 230, and the RWB interface 230 of the constant current control module 200 and the RWB port 430 of the digital potentiometer 400 are communicatively connected.

[0117] Specifically, the digital potentiometer 400 includes an RL port 480, an RH port 470, and an RWB port 430. The RL port 480 is the low-side port. The RH port 470 is the high-side port, and the RWB port 430 is the sliding contact port. In the digital potentiometer 400, the RL port 480 is typically connected to ground or the negative terminal of the circuit. Figure 3As shown, in this embodiment, RL port 480 is grounded. RH port 470 is connected to the high-voltage side; in this embodiment, RH port 470 is connected to the seventh power supply 670. RWB port 430 is the sliding port, used to indicate the sliding position of the digital potentiometer 400.

[0118] The VCC port 450 of the digital potentiometer 400 is the power supply voltage port, used to indicate the power supply voltage of the circuit. The RS port of the digital potentiometer 400 is the reset port, used to reset the internal state of the digital potentiometer 400.

[0119] In this embodiment, by setting the RWB interface 230 of the constant current control module 200 and the RWB port 430 of the digital potentiometer 400 to be communicatively connected, the voltage signal output by the digital potentiometer 400 from the RWB port 430 can be transmitted to the constant current control module 200, so that the voltage signal can change the magnitude of the maximum output current of the constant current control module 200.

[0120] The dimmable power supply 10 provided in this application, when the communication module 100 fails, cannot send an updated PWM signal. Therefore, the constant current control module 200 is set to automatically output a high or low level by default. When the communication module 100 automatically outputs a high level, the constant current control module 200 controls the output current corresponding to 100% duty cycle of the output PWM signal, and this current is used as the current output current. Since the digital potentiometer 400 does not receive a signal from the communication module 100, the resistance value of the digital potentiometer 400 will not change. The currently set maximum output current remains unchanged, and the digital potentiometer 400 still limits the output current of the constant current control module 200. Therefore, even if the constant current control module 200 controls the output current corresponding to 100% duty cycle of the output PWM signal, this current will not exceed the range unacceptable by the lamp (generally referring to the current threshold that will not exceed the lamp board burnout). Therefore, the lamp will not only work normally, but will also not burn out.

[0121] The dimmable power supply 10 will not malfunction internally.

[0122] Furthermore, when the communication module 100 automatically outputs a low level due to a fault, the constant current control module 200 controls the output current to be 0, that is, the current output current is 0. At this time, the lamp will simply not light up and will not work, and the lamp will not be burned out. Therefore, the dimmable power supply 10 provided in this embodiment will neither damage the dimmable power supply 10 nor damage the lamp.

[0123] In summary, the dimmable power supply 10 provided in this application can remotely set the maximum output current of the power supply at any time, and can also make the current output current relatively safe. This ensures that the dimmable power supply 10 and the lamp are in a very safe state when the communication module 100 fails, and both can work normally.

[0124] Optionally, the first power supply 310, the third power supply 510, and the fifth power supply 610 can share a single power supply, that is, the first power supply 310, the third power supply 510, and the fifth power supply 610 are the same power supply.

[0125] Optionally, the second power supply 320, the fourth power supply 520, the sixth power supply 620 and the seventh power supply 670 can share a single power supply, that is, the first power supply 310, the third power supply 510, the fifth power supply 610 and the seventh power supply 670 are the same power supply.

[0126] The technical features of the above embodiments can be combined arbitrarily, and the execution order of the method steps is not restricted. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0127] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A dimmable power supply, characterized in that, include: The communication module is equipped with a PWM interface; The constant current control module is equipped with a PWM port and an output port, and the PWM interface of the communication module is communicatively connected to the PWM port of the constant current control module. A digital potentiometer is disposed between the communication module and the constant current control module, and is used to change the magnitude of the currently set maximum output current of the output port of the constant current control module; The PWM interface of the communication module outputs a PWM signal and transmits it to the PWM port of the constant current control module. The duty cycle of the PWM signal is used to set the current output current of the constant current control module. The duty cycle of the PWM signal controlled by the constant current control module is positively correlated with the current output current, and the current output current is less than or equal to the currently set maximum output current.

2. The dimmable power supply according to claim 1, characterized in that, Also includes: A first level conversion circuit is disposed between the communication module and the constant current control module, and is used to convert the PWM signal output from the PWM interface of the communication module and then send it to the PWM port of the constant current control module.

3. The dimmable power supply according to claim 2, characterized in that, The first level conversion circuit includes: First power supply; Second power supply; The first transistor includes a first base, a first emitter, and a first collector; the first emitter is electrically connected to the PWM interface of the communication module, and the first collector is electrically connected to the PWM port of the constant current control module. A first resistor, the first end of which is electrically connected to the first power supply, and the second end of which is electrically connected to the first base of the first transistor; The second resistor has its first end electrically connected to the connection link between the first power supply and the first resistor, and its second end electrically connected to the connection link between the PWM interface of the communication module and the first emitter of the first transistor. The first capacitor includes a first plate and a second plate. The first plate of the first capacitor is electrically connected to the connection link between the first end of the first resistor and the first end of the second resistor. The second plate of the first capacitor is electrically connected to the connection link between the first resistor and the first base of the first transistor. The third resistor has its first end electrically connected to the second power supply, and its second end electrically connected to the connection link between the first collector of the first transistor and the PWM port of the constant current control module.

4. The dimmable power supply according to claim 3, characterized in that, Also includes: The second level conversion circuit is located between the communication module and the constant current control module, and is used to convert the first voltage signal output from the INC interface of the communication module and then send it to the INC port of the digital potentiometer.

5. The dimmable power supply according to claim 4, characterized in that, The second level conversion circuit includes: Third power supply; Fourth power supply; The second transistor includes a second base, a second emitter, and a second collector; the second emitter is electrically connected to the INC interface of the communication module, and the second collector is electrically connected to the INC port of the digital potentiometer. The fourth resistor has its first end electrically connected to the third power supply, and its second end electrically connected to the second base of the second transistor. The second capacitor includes a third plate and a fourth plate. The third plate of the second capacitor is electrically connected to the connection link between the third power supply and the first end of the fourth resistor. The fourth plate of the second capacitor is electrically connected to the connection link between the second end of the fourth resistor and the second base of the second transistor. The fifth resistor has its first end electrically connected to the fourth power supply, and its second end electrically connected to the connection link between the second collector of the second transistor and the INC port of the digital potentiometer.

6. The dimmable power supply according to claim 5, characterized in that, Also includes: The third level conversion circuit is located between the communication module and the constant current control module, and is used to convert the level of the second voltage signal output from the U / D interface of the communication module and then send it to the U / D port of the digital potentiometer.

7. The dimmable power supply according to claim 6, characterized in that, The third level conversion circuit includes: Fifth power supply; Sixth power supply; The third transistor includes a third base, a third emitter, and a third collector; the third emitter is electrically connected to the U / D interface of the communication module, and the third collector is electrically connected to the U / D port of the digital potentiometer. The sixth resistor, the second end of which is electrically connected to the third base of the third transistor; The third capacitor includes a fifth plate and a sixth plate. The fifth plate of the third capacitor is electrically connected to the fifth power supply, and the sixth plate of the third capacitor is electrically connected to the connection link between the second terminal of the sixth resistor and the third base of the third transistor. The first terminal of the sixth resistor is electrically connected to the connection link between the fifth power supply and the fifth plate of the third capacitor. The seventh resistor has its first end electrically connected to the sixth power supply, and its second end electrically connected to the connection link between the third collector of the third transistor and the U / D port of the digital potentiometer.

8. The dimmable power supply according to claim 7, characterized in that, The constant current control module is equipped with an RWB interface, and the RWB interface of the constant current control module is communicatively connected to the RWB port of the digital potentiometer.

Images