Dimming interface control circuit and dimming system compatible with multiple dimming methods

Abstract

This invention provides a dimming interface control circuit and dimming system compatible with multiple dimming methods. The dimming interface control circuit is coupled to both a DALI bus and a DALI control device, and includes a first power supply module, a transmitting control module, a receiving control module, and a button dimming control module. It is compatible with both DALI dimming and button dimming methods, simplifying the peripheral circuitry of the dimming interface control circuit. Compared to existing interface circuits composed of discrete components, it offers better consistency and requires fewer external components. Furthermore, MOSFETs are used in the transmitting control module and / or receiving control module for signal path switching control, resulting in high precision, low temperature drift, and better consistency. In addition, an overvoltage protection circuit is integrated into the button dimming control module, thereby achieving overvoltage protection for the chip while maintaining compatibility with button dimming signal transmission and meeting the high voltage withstand requirements of button dimming.

Description

Technical Field

[0001] This invention relates to the field of intelligent lighting control technology, and in particular to a dimming interface control circuit and dimming system compatible with multiple dimming modes. Background Technology

[0002] DALI (Digital Addressable Lighting Interface) is a lighting standard defined by IEC 62386. A single DALI bus can connect up to 64 input devices and 64 control gears. DALI control devices refer to the controlled lighting equipment, such as LED lamps, relays, and MCU devices used to receive control commands and directly control the lamps. Control devices refer to application controllers and input devices that issue control commands or generate trigger events, such as DALI switches, DALI knobs, and DALI sensors.

[0003] The DALI bus can power DALI control devices and equipment connected to the bus, and can also be used for communication signal transmission. The maximum power supply current on the DALI bus is 250mA. As a wired intelligent lighting technology, the biggest feature of DALI is that each lamp has an independent address. It can independently address single lamps or groups of lamps on the same power circuit or different circuits, realizing individual dimming control and arbitrary group dimming control. Therefore, DALI dimming technology brings great flexibility to lighting control. Users can adjust the functions as needed during operation after installation without making any changes to the wiring. It is widely used in large venues, commercial lighting and office lighting control systems.

[0004] The aforementioned DALI control device connects to the DALI bus via an interface circuit to communicate with control equipment and receive and transmit signals. Current interface circuits generally use discrete components such as transistors. Constant current and current limiting functions are achieved by limiting the current through the voltage difference VBE between the base and emitter of the transistor, which results in poor accuracy, severe temperature dependence, and drawbacks such as complex external components, poor consistency, and high cost. Similarly, overvoltage protection circuits typically achieve overvoltage protection through voltage division using a Zener diode and the VBE sensing resistor of the transistor, also resulting in poor accuracy and severe temperature dependence. Summary of the Invention

[0005] The purpose of this invention is to provide a dimming interface control circuit and dimming system that is compatible with multiple dimming methods, can be compatible with DALI dimming and button dimming, simplifies the peripheral circuit design, improves consistency, and meets the high voltage resistance requirements of button dimming.

[0006] To achieve the above objectives, the present invention provides a dimming interface control circuit compatible with multiple dimming methods, characterized in that it includes:

[0007] The transmission control module is coupled to the DALI bus and the DALI control device respectively, and is used to upload the signals sent by the DALI control device to the DALI bus;

[0008] The receiving control module is coupled to the DALI bus and the DALI control device respectively, and is used to send the dimming signal on the DALI bus to the DALI control device.

[0009] A button dimming control module is coupled to the DALI bus, the transmitting control module, and the receiving control module, respectively. It detects the voltage of the DALI bus during button dimming. When the detected voltage of the DALI bus rises above the internal reference voltage, it controls the transmitting control module and the receiving control module to turn off. When the detected voltage of the DALI bus falls below the internal reference voltage, it controls the receiving control module to turn on, so that the dimming signal on the DALI bus is transmitted to the DALI control device through the receiving control module.

[0010] The first power supply module is coupled to the energy storage capacitor, the DALI bus, the transmitting control module, the receiving control module, and the key dimming control module, respectively. It is used to charge the energy storage capacitor when the DALI bus is high, and to provide corresponding reference voltages to the transmitting control module, the receiving control module, and the key dimming control module, respectively.

[0011] Optionally, the first power supply module includes a power supply switch and a bandgap reference voltage source. One end of the power supply switch is coupled to the DALI bus, and the other end is coupled to the bandgap reference voltage source and the energy storage capacitor, respectively. When the power supply switch is turned on and the DALI bus is at a high level, the energy storage capacitor is charged. The bandgap reference voltage source provides corresponding reference voltages to the transmitting control module, the receiving control module, and the key dimming control module, respectively.

[0012] Optionally, the transmission control module includes a first MOSFET and a first operational amplifier. The gate of the first MOSFET is coupled to the output terminal of the first operational amplifier, the drain of the first MOSFET is coupled to the DALI bus, the source of the first MOSFET is coupled to the second input terminal of the first operational amplifier and the first terminal of the first current-limiting resistor, the second terminal of the first current-limiting resistor is coupled to ground, the first input terminal of the first operational amplifier is coupled to the bandgap reference voltage source to receive the first reference voltage, and the enable terminal of the first operational amplifier is coupled to the DALI control device and the key dimming control module.

[0013] Optionally, the transmission control module is coupled to the DALI bus via a second constant current source having a second MOS transistor, wherein the second MOS transistor is coupled in series with the first MOS transistor.

[0014] Optionally, the transmission control module is coupled to the DALI control device via a first optical coupler.

[0015] Optionally, the receiving control module includes a third MOS transistor and a second operational amplifier. The gate of the third MOS transistor is coupled to the output terminal of the second operational amplifier. The drain of the third MOS transistor is coupled to the DALI bus and the DALI control device, respectively. The source of the third MOS transistor is coupled to the second input terminal of the second operational amplifier and the first terminal of the second current-limiting resistor, respectively. The second terminal of the second current-limiting resistor is coupled to ground. The first input terminal of the second operational amplifier is coupled to the bandgap reference voltage source to receive the second reference voltage. The enable terminal of the second operational amplifier is coupled to the key dimming control module.

[0016] Optionally, the receiving control module is coupled to the DALI control device and the DALI bus respectively via a second optocoupler.

[0017] Optionally, the second optocoupler is coupled to the DALI bus via a first constant current source having a fourth MOS transistor, which is connected in series with the third MOS transistor.

[0018] Optionally, the button dimming control module includes an overvoltage protection circuit. The first input terminal of the overvoltage protection circuit is coupled to the DALI bus to receive the voltage division of the DALI bus. The second input terminal of the overvoltage protection circuit is coupled to the bandgap reference voltage source to receive the internal reference voltage. The output terminal of the overvoltage protection circuit is coupled to the transmitting control module and the receiving control module respectively. When the voltage division is higher than the internal reference voltage, the transmitting control module and the receiving control module are turned off. When the voltage division is lower than the internal reference voltage, the receiving control module is turned on.

[0019] Optionally, the dimming interface control circuit is integrated into a chip, the chip having:

[0020] The signal receiving pin is coupled to the receiving control module, the DALI bus, and the DALI control device.

[0021] The signal transmission pin is coupled to the transmission control module and the DALI control device;

[0022] A button dimming control pin is coupled to the DALI bus and the button dimming control module;

[0023] The high-voltage pin is coupled to the DALI bus and the first power supply module;

[0024] The power supply pin is coupled to the energy storage capacitor and the first power supply module;

[0025] The sampling pin is coupled to the first current-limiting resistor and the transmission control module;

[0026] The drain pin is coupled to the DALI bus and the transmit control module; and

[0027] Grounding pin, coupled to ground.

[0028] Optionally, the button dimming control pin is coupled to one end of the first voltage divider resistor and one end of the second voltage divider resistor, the other end of the first voltage divider resistor is coupled to the DALI bus, and the other end of the second voltage divider resistor is coupled to ground.

[0029] Based on the same inventive concept, the present invention also provides a dimming system, which includes: a DALI bus, at least one DALI control device, and a dimming interface control circuit as described in the present invention, which is compatible with multiple dimming modes and is configured in one-to-one correspondence with the DALI control device. The dimming interface control circuit is coupled to the DALI bus and the DALI control device respectively.

[0030] Optionally, the dimming system further includes a DALI host, and the DALI bus is coupled to the DALI host.

[0031] Optionally, the dimming system further includes a dimming button, with one end of the DALI bus coupled to the dimming button and the other end of the dimming button coupled to the live wire of the AC power supply.

[0032] Optionally, the dimming system further includes a rectifier circuit coupled between the DALI bus and the dimming interface control circuit.

[0033] Compared with the prior art, the technical solution of the present invention has at least one of the following beneficial effects:

[0034] 1. The dimming interface control circuit compatible with multiple dimming modes is coupled to the DALI bus and the DALI control device respectively, and includes a first power supply module, a transmitting control module, a receiving control module and a button dimming control module, which can be compatible with both DALI dimming and button dimming modes.

[0035] 2. It can simplify the peripheral circuit. Compared with the interface circuit formed by existing discrete components, it has better consistency, better versatility, and fewer peripheral components.

[0036] 3. Using MOSFETs in the transmit control module and / or receive control module for switching control of the signal path results in high precision, low temperature drift, and better consistency.

[0037] 4. An additional constant current source is connected in series between the transmit control module and / or receive control module and the DALI bus. The MOS switches of these constant current sources are used for constant current and current limiting, which has high accuracy, low temperature drift and improves the circuit’s surge protection capability.

[0038] 5. An overvoltage protection circuit is integrated into the button dimming control module, thereby achieving the chip's overvoltage protection function while maintaining compatibility with button dimming signal transmission, and meeting the high voltage resistance requirements of button dimming. Attached Figure Description

[0039] Those skilled in the art will understand that the accompanying drawings are provided to better understand the invention and do not constitute any limitation on the scope of the invention. Wherein:

[0040] Figure 1 This is a schematic diagram of the architecture of a dimming interface control circuit with compatibility with multiple dimming modes according to the first embodiment of the present invention.

[0041] Figure 2 This is a schematic diagram of the architecture of the dimming system according to the first embodiment of the present invention.

[0042] Figure 3 yes Figure 2 The diagram shown illustrates the wiring of the dimming system used to implement DALI dimming.

[0043] Figure 4 yes Figure 2 The diagram shown illustrates the wiring of the dimming system used to implement button dimming.

[0044] Figure 5 This is a schematic diagram of an example architecture of a dimming system according to the second embodiment of the present invention.

[0045] Figure 6 yes Figure 5 The diagram shows the internal circuit architecture of the constant current source in the dimming system.

[0046] Figure 7 This is a schematic diagram of another example architecture of the dimming system according to the second embodiment of the present invention. Detailed Implementation

[0047] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the invention. It should be understood that the invention can be embodied in various forms and should not be construed as limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The same reference numerals denote the same elements throughout. It should be understood that when an element is referred to as "connected to" or "coupled to" other elements, it may be directly connected to other elements, or there may be intervening elements. Conversely, when an element is referred to as "directly connected to" other elements, there are no intervening elements. As used herein, the singular forms "a," "an," and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "comprising" is used to identify the presence of features, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups. When used herein, the term "and / or" includes any and all combinations of the associated listed items.

[0048] The technical solution proposed by the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0049] First Embodiment

[0050] Please refer to Figure 1 and Figure 2 This embodiment provides a dimming interface control circuit U1 (hereinafter referred to as "dimming interface control circuit U1") that is compatible with multiple dimming modes. It is coupled to the DALI bus DALI+, DALI- and the DALI control device DALI MCU respectively. It is used to receive the power provided by the DALI bus DALI+ and realize the signal transmission between the DALI control device DALI MCU and the DALI bus DALI+ and DALI-.

[0051] As an example, the dimming interface control circuit U1 includes a transmitting control module 11, a receiving control module 12, a key dimming control module 13, and a first power supply module 10.

[0052] The first power supply module 10 is coupled to the energy storage capacitor C0, the DALI bus DALI+ and DALI-, the transmitting control module 11, the receiving control module 12, and the key dimming control module 13, respectively. When the DALI bus DALI+ is at a high level, it charges the energy storage capacitor C0, thereby providing the corresponding reference voltage to the transmitting control module 11, the receiving control module 12, the key dimming control module 13, and other circuit modules.

[0053] In this embodiment, during DALI dimming, a square wave signal is transmitted on the DALI bus DALI+, and the voltage on the DALI bus DALI+ is high when above 9.5V and low when below 6.5V. During button dimming, the voltage on the DALI bus is a power frequency sine wave.

[0054] The first power supply module 10 can be implemented using any suitable circuit design. For example, please refer to... Figure 1 and Figure 2 The first power supply module 10 includes a power supply switch 102 and a bandgap reference voltage source 101. One end of the power supply switch 102 is connected to a current-limiting resistor R. HV The first end is coupled to the DALI bus DALI+, and the other end is coupled to the energy storage capacitor C0 and the bandgap reference voltage source 101. The bandgap reference voltage source 101 generates the first reference voltage VREF1, the second reference voltage VREF2 and the internal reference voltage VREF according to the voltage of the energy storage capacitor (i.e. the voltage of the power supply pin VCC), so as to adaptively provide them to the transmitting control module 11, the receiving control module 12, the key dimming control module 13 and so on.

[0055] The transmission control module 11 is coupled to the DALI control device DALI MCU and the DALI bus DALI+ respectively. The transmission control module 11 is used to convert the transmission signal sent by the DALI control device DALI MCU into a DALI signal and upload it to the DALI bus DALI+. The DALI signal provides feedback on information such as the brightness of the current lamp under DALI dimming.

[0056] The transmission control module 11 can be implemented using any suitable circuit design. As an example, the transmission control module 11 includes a first MOSFET M1 and a comparator module 111 with a first operational amplifier OP1. The gate of the first MOSFET M1 is coupled to the output terminal of the first operational amplifier OP1, the drain DRAIN of the first MOSFET M1 is coupled to the DALI bus DALI+, the source of the first MOSFET M1 is coupled to the second input terminal of the first operational amplifier OP1 and one end of the first current-limiting resistor Rcs, the other end of the first current-limiting resistor Rcs is coupled to ground, and the first input terminal of the first operational amplifier OP1 is coupled to a bandgap reference voltage source 101 to receive the first reference voltage VREF1 output by the bandgap reference voltage source 101. Thus, the first operational amplifier OP1 amplifies the error between the voltage at one end of the first current-limiting resistor Rcs (i.e., the magnitude of the pull-down current set by the first current-limiting resistor Rcs) and the first reference voltage VREF1, and controls the on-resistance of the first MOSFET M1 according to the error amplification result. Both the DALI control device DALI MCU and the key dimming control module 13 are coupled to the enable terminal of the first operational amplifier OP1. The DALI control device DALI MCU sends high or low level signals, while the enable terminal of the first operational amplifier OP1 receives a PWM signal. The first operational amplifier OP1 is enabled or disabled based on this PWM signal. When enabled by the PWM signal, the first operational amplifier OP1 can control the conduction or cutoff of the first MOSFET M1 according to the high or low level of the send signal from the DALI control device DALI MCU. When the send signal from the DALI control device DALI MCU is high, the first MOSFET M1 is turned on, and the voltage at its drain DRAIN is pulled low. Conversely, when the send signal from the DALI control device DALI MCU is low, the first MOSFET M1 is cut off, and the voltage at its drain DRAIN is high. This affects the voltage change on the DALI bus DALI+, thus achieving the function of transmitting signals from the DALI control device DALI MCU to the DALI bus.

[0057] In the transmission control module 11, the first MOSFET M1 is used to control the switching of the signal path, which has high precision, low temperature drift and better consistency.

[0058] Optionally, please combine Figure 1 and Figure 2The transmitting control module 11 is coupled to the DALI control device DALI MCU via the first optocoupler U3. Specifically, the transmitting control module 11 is coupled to one end of the light receiver in the first optocoupler U3, the other end of the light receiver in the first optocoupler U3 is grounded, and both ends of the light emitter in the first optocoupler U3 are connected to the DALI control device DALI MCU, thereby achieving the coupling between the transmitting control module 11 and the DALI control device DALI MCU. The dimming interface control circuit also includes a resistor R0, one end of which is coupled to the energy storage capacitor C0, and the other end of which is coupled to one end of the light receiver in the first optocoupler U3. Thus, the dimming interface control circuit U1 can receive the transmitting signal (not shown) sent by the DALI control device DALI MCU through the first optocoupler U3, and further convert it into a DALI signal and upload it to the DALI bus DALI+. The first optocoupler U3 is used to achieve corresponding signal isolation when the dimming interface control circuit U1 uploads the transmitting signal sent by the DALI control device DALI MCU to the DALI bus DALI+.

[0059] The receiving control module 12 is coupled to the DALI control device DALI MCU and the DALI bus DALI+ and DALI- respectively. When DALI dimming is performed, the dimming signals on the DALI bus DALI+ and DALI- are sent to the DALI control device DALI MCU. The dimming signals include DALI dimming signals and button dimming signals.

[0060] The receiving control module 12 can be implemented using any suitable circuit design. As an example, the receiving control module 12 includes a third MOSFET M2 and a comparator module 121 with a second operational amplifier OP2. The gate of the third MOSFET M2 is coupled to the output terminal of the second operational amplifier OP2, the drain of the third MOSFET M2 is coupled to the DALI bus DALI+, the source of the third MOSFET M2 is coupled to the second input terminal of the second operational amplifier OP2 and one end of the second current-limiting resistor R1, the other end of the second current-limiting resistor R1 is coupled to ground, the first input terminal of the second operational amplifier OP2 is coupled to the second reference voltage VREF2 output by the bandgap reference voltage source 101, and the enable terminal of the second operational amplifier OP2 is coupled to the key dimming control module 13. Therefore, the second operational amplifier OP2 compares the voltage at one end of the second current-limiting resistor R1 with the second reference voltage VREF2, and controls the operation of the third MOSFET M2 according to the comparison result. For example, it controls M2 to work in a weak conduction state, so that the second operational amplifier OP2, the third MOSFET M2 and the second current-limiting resistor R1 form a constant current source, thereby converting the DALI dimming signal on the DALI bus DALI+ into high and low level signals that can be recognized by the DALI control device DALI MCU, so as to achieve the function of DALI dimming.

[0061] The receiving control module 12 uses a third MOSFET M2 to control the switching of the signal path, which has high precision, low temperature drift, and better consistency.

[0062] Optionally, the receiving control module 12 is coupled to the DALI control device DALI MCU and the DALI bus DALI+ via the second optocoupler U2. Specifically, the receiving control module 12 is coupled to one end of the emitter in the second optocoupler U2, the other end of the emitter in the second optocoupler U2 is coupled to the DALI bus DALI+ (i.e., the output of the rectifier circuit U0), and both ends of the receiver in the second optocoupler U2 are coupled to the DALI control device DALI MCU. Thus, when the second optocoupler U2 is turned on, the dimming interface control circuit U1 can receive the DALI dimming signal from the DALI bus receiving control module 12, convert the received DALI dimming signal into a signal allowed by the DALI control device DALI MCU, and then transmit it to the DALI control device DALI MCU to achieve the DALI dimming function. The second optocoupler U2 is used to achieve corresponding signal isolation when the dimming interface control circuit U1 receives DALI dimming signals from the DALI bus DALI+ and DALI- and transmits the received DALI dimming signals to the DALI control device DALI MCU.

[0063] The button dimming control module 13 is coupled to the first power supply module 10, the transmitting control module 11, the receiving control module 12, and the DALI bus DALI+. When dimming with the buttons, please combine... Figure 1 and Figure 4 When the dimming button S is closed, the DALI bus DALI+ is connected to the live wire L of the AC power supply, forcing the voltage on the DALI bus DALI+ to rise rapidly. At this time, the voltage on the DALI bus DALI+ becomes a sine wave at the power frequency. The button dimming control module 13 detects the voltage on the DALI bus DALI+ and determines whether the voltage on the DALI bus DALI+ has risen above the internal reference voltage VREF provided by the first power supply module 10. When it is determined that the voltage on the DALI bus DALI+ has risen above the internal reference voltage VREF, the first MOSFET of the transmitting control module 11 and the third MOSFET of the receiving control module 12 are both turned off. When it is determined that the voltage on the DALI bus DALI+ has dropped below the internal reference voltage VREF, the third MOSFET of the receiving control module 12 is turned on, so that the receiving control module 12 can transmit the button dimming signal (e.g., PWM signal) on the DALI bus DALI+ to the DALI control device DALI MCU through the receiving control module 12 and the second optocoupler U2, thereby realizing the button dimming function. It should be noted that when the voltage on the DALI+ bus drops below the internal reference voltage VREF, the button dimming control module 13 enables the transmitting control module 11, but does not control the first MOSFET to conduct. Whether the first MOSFET conducts is determined by the DALI controller MCU. It should be understood that in button dimming mode, when the voltage on the DALI+ bus is greater than VREF, the signal receiving pin RX goes high; otherwise, RX goes low. Therefore, the signal receiving pin RX transmits the button dimming signal to the DALI controller MCU in the form of a PWM signal. The DALI controller MCU distinguishes between the button dimming signal in button dimming mode and the DALI dimming signal in DALI dimming mode, and then controls the lighting driver (e.g., ...). Figure 4 The button dimming function is implemented using U5 (as shown in the figure).

[0064] The button dimming control module 13 can employ any suitable circuit design. As an example, the button dimming control module 13 includes an overvoltage protection circuit OVP. The first input terminal of the overvoltage protection circuit OVP is coupled to the DALI bus DALI+, and the second input terminal is coupled to the bandgap reference voltage source 101 to receive the internal reference voltage VREF. The output terminal of the overvoltage protection circuit OVP is coupled to the enable terminal of the first operational amplifier OP1 (i.e., the en terminal of OP1) and the enable terminal of the second operational amplifier OP2 (i.e., the en terminal of OP2). Furthermore, when dimming the button, please combine... Figure 1 and Figure 4 When the dimming button S is closed, and the overvoltage protection circuit OVP detects that the voltage on the DALI bus DALI+ has risen above the internal reference voltage VREF, it controls both the first operational amplifier OP1 and the second operational amplifier OP2 to be disabled, i.e., both the first operational amplifier OP1 and the second operational amplifier OP2 are disabled, and neither the first operational amplifier OP1 nor the second operational amplifier OP2 has any output. This controls both the first MOS transistor M1 in the transmitting control module 11 and the third MOS transistor M2 in the receiving control module 12 to be turned off. When the voltage on the DALI bus DALI+ drops to or below the internal reference voltage VREF, it controls both the first operational amplifier OP1 and the second operational amplifier OP2 to be enabled, and the second operational amplifier OP2 has a corresponding output. This controls both the third MOS transistor M2 in the receiving control module 12 to be turned on, thereby realizing the transmission of the button dimming signal from the DALI bus DALI+ to the DALI control device DALIMCU.

[0065] The overvoltage protection circuit (OVP) of the key dimming control module 13 not only enables the transmission of key dimming signals and meets the high voltage resistance requirements of key dimming, but also provides overvoltage protection with high precision and low temperature drift.

[0066] Please combine Figures 1 to 4The working principle of the dimming interface control circuit U1 in this embodiment is as follows: During the dimming process, the third MOS transistor M2 of the receiving control module 12 and the second operational amplifier OP2 form a constant current and current limiting structure, and the third MOS transistor M2 is always weakly conducting. The DALI control device DALI MCU processes the dimming signal (which can be a DALI dimming signal or a button dimming signal) received from the second optocoupler U2, thereby controlling the output of the lighting driver (e.g., an LED driver) U5 connected to the DALI control device DALI MCU, and realizing the dimming of the lamp U6. Furthermore, the DALI control device DALIMCU feeds back the current brightness and other status information of the lamp U6 (i.e., the DALI MCU sends a corresponding transmission signal), which is transmitted to the transmission control module 11 via the first optocoupler U3. The transmission control module 11 feeds back the current status information of the lamp U6 to the DALI bus DALI+. The DALI host (not shown) then determines whether to further brighten or dim the lamp U6 based on the current brightness information of the lamp U6 transmitted from the DALI bus DALI+. The DALI host then changes the voltage duty cycle on the DALI bus DALI+, and the receiving control module 13 further sends the new dimming information to the DALI control device DALI MCU. As a result, the dimming signal received by the DALI control device DALI MCU from the second optocoupler U2 changes compared to the previously received dimming signal, further controlling the output of the lighting driver (e.g., an LED driver) U5 to dim the lamp U6 again. This process is repeated, so the voltage on the DALI bus DALI+ becomes a changing square wave signal, which includes the dimming signal and the DALI control device DALI MCU's signal. The current brightness information of lamp U6 is fed back by the MCU.

[0067] Optionally, in this embodiment, the dimming interface control circuit U1 is coupled to the DALI bus DALI+ and DALI- through a rectifier circuit U0. The main function of the rectifier circuit U0 is to allow the DALI bus DALI+ and DALI- to be connected without distinguishing polarity, thus facilitating subsequent wiring. Here, the rectifier circuit U0 also serves as a reverse polarity protection mechanism.

[0068] Optionally, the rectifier circuit U0 may also be coupled to the DALI bus DALI+, DALI- with: a current limiting protector FR1 for limiting the current of the transmitted signal, and a varistor Z0 for clamping the voltage on the DALI bus DALI+, DALI-.

[0069] Furthermore, to simplify the peripheral circuitry of the dimming interface control circuit, improve consistency, and enhance versatility, in this embodiment, the dimming interface control circuit U1 is integrated into a single chip (i.e., an interface chip). This chip has a signal receiving pin RX, a signal transmitting pin TX, a button dimming control pin VS, a high-voltage pin HV, a power supply pin VCC, a sampling pin CS, a ground pin GND, and a drain pin DRAIN. The second optocoupler U2 and the first optocoupler U3 are both located outside this chip.

[0070] The signal transmission pin TX is coupled to one end of the receiver of the transmission control module 11 and the first optocoupler U3. The high and low levels on the signal transmission pin TX (obtained from the current status information of the lamps sent by the DALI control device DALI MCU) are converted into high and low voltages on the drain pin DRAIN, which in turn affect the voltage change on the DALI bus DALI+, so as to achieve the function of sending signals (i.e. feedback information) from the DALI control device DALI MCU to the DALI bus DALI+.

[0071] The signal receiving pin RX is coupled to one end of the emitter of the receiving control module 12 and the second optocoupler U2. Thus, when the second optocoupler U2 is turned on, the receiving control module 12 of the dimming interface control circuit U1 can receive the dimming signals (which can be DALI dimming signals or button dimming signals) on the DALI bus DALI+ and DALI-, and convert the received dimming signals into signals allowed by the DALI control device DALI MCU, and then transmit them to the DALI control device DALI MCU.

[0072] The button dimming control pin VS is coupled to one end of the first voltage divider resistor Ra and one end of the second voltage divider resistor Rb outside the chip. The other end of the first voltage divider resistor Ra is coupled to the output terminal of the rectifier circuit U0, and the other end of the second voltage divider resistor Rb is coupled to ground. This achieves the coupling of the button dimming control pin VS with the DALI bus DALI+ and DALI-. When dimming is performed by the button, the dimming button S is closed, connecting the DALI bus DALI+ to the live wire of the AC power supply (e.g., ...). Figure 4On the L line (in the middle), the voltage of the DALI bus DALI+ increases. At this time, the voltage on the DALI bus DALI+ becomes a sine wave of the power frequency. The button dimming control module 13 detects the voltage on the DALI bus DALI+ through the button dimming control pin VS. When the voltage on the DALI bus DALI+ is detected to rise above the internal reference voltage, the first operational amplifier OP1 in the transmitting control module 11 and the second operational amplifier OP2 in the receiving control module 12 are disabled, causing the first MOS transistor M1 in the transmitting control module 11 to turn off and the third MOS transistor M2 in the receiving control module 12 to turn off, and the signal receiving pin RX becomes high level. When the voltage on the DALI bus DALI+ is detected to drop below the internal reference voltage, the first operational amplifier OP1 in the transmitting control module 11 and the second operational amplifier OP2 in the receiving control module 12 are enabled, causing the third MOS transistor M2 in the receiving control module 12 to turn on, and the signal receiving pin RX becomes low level. Thus, the signal receiving pin RX will transmit the corresponding button dimming signal from the DALI bus DALI+ to the DALI control device DALI MCU in the form of a PWM signal.

[0073] The drain pin DRAIN is coupled to the DALI bus DALI+, and is coupled to the signal transmission pin TX through the transmission control module 11, thereby transmitting the signal received by the signal transmission pin TX to the DALI bus DALI+.

[0074] The power supply pin VCC is coupled to one end of an external energy storage capacitor C0, and the other end of C0 is coupled to ground. The high-voltage pin HV is coupled to an external current-limiting resistor R. HV One end, current-limiting resistor R HV The other end is coupled to one end of the rectifier circuit U0, thereby achieving the coupling of the high-voltage pin HV with the DALI bus DALI+ and DALI-. When the voltage on the DALI bus DALI+ is high, the dimming interface control circuit U1 can draw power from the DALI bus DALI+ through the high-voltage pin HV and supply power to the energy storage capacitor C0 through the power supply pin VCC, thereby providing the corresponding reference voltage for the internal circuit of the dimming interface control circuit U1 chip.

[0075] The sampling pin CS is coupled to one end of the first current-limiting resistor Rcs outside the chip, and the other end of the first current-limiting resistor Rcs is coupled to ground. When the first optocoupler U3 is turned on, the maximum pull-down current of the transmitting control module 11 is set by the first current-limiting resistor Rcs. The high and low levels of the signal transmitting pin TX can control the on and off of the pull-down current of the transmitting control module 11. Thus, when the first optocoupler U3 is turned on, the signal transmitting pin TX turns on the pull-down current of the transmitting control module 11, and when the first optocoupler U3 is turned off and the signal transmitting pin TX turns off the pull-down current of the transmitting control module 11. The transmitting control module 11 can transmit the signal output by the DALI MCU of the DALI control device to the DALI bus DALI+.

[0076] The ground pin GND is coupled to the ground terminal of the chip, as well as the energy storage capacitor C0 and the first current limiting resistor Rcs, to realize the common ground of the chip and its peripheral circuits.

[0077] The aforementioned resistors, capacitors, etc. are all located outside the chip with the dimming interface control circuit U1. However, the technical solution of the present invention is not limited to this. If the area of ​​the chip allows, these resistors and capacitors can also be integrated into the chip.

[0078] Please refer to Figures 1 to 4 This embodiment also provides a dimming system, which includes: DALI buses DALI+ and DALI-, at least one DALI control device DALI MCU, a dimming interface control circuit U1 as described in this invention, which is configured one-to-one with the DALI control device DALI MCU, and a second optocoupler U2, a first optocoupler U3 and a rectifier circuit U0.

[0079] The dimming interface control circuit U1 is coupled to the DALI bus DALI+ and DALI- through the rectifier circuit U0, and is coupled to the DALI control device DALI MCU through the second optocoupler U2 and the first optocoupler U3.

[0080] As an example, please refer to Figure 3The dimming system in this embodiment can be used for DALI dimming. In this case, the dimming system may further include a DALI host U4, a lighting driver U5, and a luminaire U6. The lighting driver U5 is coupled to the live wire L and neutral wire N of the AC power supply, the DALI control device DALI MCU, and the luminaire U6. The DALI control device DALI MCU obtains the corresponding dimming signals from the DALI host U4 via the second optocoupler U2 and the dimming interface control circuit U1, and generates corresponding control signals for the lighting driver U5, thereby enabling the lighting driver U5 to drive the luminaire U6 to change its brightness, color temperature, etc. Meanwhile, the DALI control device DALI MCU also sends the current status information of the lamp 16 (including brightness, color temperature, etc.) to the DALI bus DALI+ through the first optocoupler U3 and the dimming interface control circuit U1, so that the DALI bus power supply can know it, thereby enabling the DALI host U4 to generate the next dimming signal according to the current status information of the lamp 16 (including brightness, color temperature, etc.), and then realize the adjustment of the brightness and color temperature of the lamp U6 again.

[0081] As another example, please refer to Figure 4 The dimming system of this embodiment can be used for button dimming. In this case, the dimming system may further include a dimming button S, a lighting driver U5, and a luminaire U6. The lighting driver U5 is coupled to the live wire L and neutral wire N of the AC power supply, the DALI control device DALI MCU, and the luminaire U6. One end of the dimming button S is coupled to the live wire L of the AC power supply, and the other end is coupled to the DALI bus DALI+. When button dimming is needed, the dimming button S is closed, the DALI bus DALI+ is connected to the live wire L of the AC power supply, and the DALI control device DALI MCU obtains the corresponding button dimming signal from the DALI bus DALI+ through the second optocoupler U2 and the dimming interface control circuit U1, and generates a corresponding control signal to the lighting driver U5, thereby enabling the lighting driver U5 to drive the luminaire U6 to change its brightness, color temperature, etc.

[0082] The dimming system in this embodiment, due to the use of the dimming interface control circuit of the present invention which is compatible with multiple dimming methods, is compatible with DALI dimming and button dimming functions, and its performance is improved.

[0083] Second Embodiment

[0084] Please refer to Figures 5 to 7This embodiment provides a dimming interface control circuit U1 (hereinafter referred to as "dimming interface control circuit U1") and a dimming system that are compatible with multiple dimming methods. The circuit design and chip pin design of the dimming interface control circuit U1 are the same as those of the dimming interface control circuit U1 in the first embodiment. However, the difference is that, in order to improve the surge protection capability of the dimming interface control circuit U1, the dimming interface control circuit U1 of this embodiment further connects an additional first constant current source U7 (i.e., the second optocoupler U2 and the DALI bus are connected in series with the first constant current source U7) in series between its receiving control module 12 and the DALI bus DALI+, and / or, further connects an additional second constant current source U8 (i.e., the drain pin DRAIN is further connected in series with the additional second constant current source U8) in series between its transmitting control module 11 and the DALI bus DALI+.

[0085] As an example, please refer to Figure 5 and Figure 6 In this embodiment, an additional first constant current source U7 is connected in series with the signal receiving pin RX of the dimming interface control circuit U1 to improve surge protection. This first constant current source U7 can be a conventional constant current source chip, externally equipped with pins 1-3, and internally equipped with a second power supply module 20, an LDO constant current control module 21, and a second MOSFET M0. The input terminal of the second power supply module 20 is coupled to the corresponding power supply voltage VDD, and the output terminal is coupled to the drain (D) of the second MOSFET M0 and pin 1. Pin 1 is also coupled to the output terminal DALI bus of the rectifier circuit U0. The second power supply module 20 is used to draw power from the DALI bus and provide the corresponding drain voltage to the drain D of the second MOSFET M0. One input terminal of the LDO constant current control module 21 is grounded, and the other input terminal is coupled to the source (CS) of the second MOSFET M0 and pin 2. The output terminal of the LDO constant current control module 21 can be directly or through a gate resistor GT coupled to the gate of the second MOSFET M0 to control the conduction or cutoff of the second MOSFET M0. Pin 2 is also coupled to an external resistor R. RX At one end, pin 3 is coupled to resistor R. RX The other end and one end of the emitter of the second optocoupler U2. Thus, the signal receiving pin RX of the dimming interface control circuit U1, which is compatible with multiple dimming modes, is coupled to the first constant current source U7 through the second optocoupler U2 and pin 3, and combined with... Figure 2 As shown, M2 in the receiver control module 12 of the dimming interface control circuit U1 is connected in series with the second MOS transistor M0 in the first constant current source U7.

[0086] Please combine Figures 1 to 6After a surge occurs, the overvoltage protection circuit OVP in the button dimming control module 13 of the dimming interface control circuit U1 will shut down M1 and M2 inside the dimming interface control circuit U1. Since M0 in the first constant current source U7 is connected in series at the RX pin, M0 can share part of the surge voltage, which makes M2 less likely to be broken down and the dimming interface control circuit U1 less likely to fail, thus enhancing its surge resistance capability.

[0087] As another example, please refer to Figure 7 In this embodiment, an additional first constant current source U7 is connected in series at the signal receiving pin RX of the dimming interface control circuit U1, and an additional second constant current source U8 is connected in series at the drain pin DRAIN to maximize surge protection. The first constant current source U7 has a second MOSFET, and the second constant current source U8 has a fourth MOSFET. The functions of pins 1-3 of the first constant current source U7 and the second constant current source U8 are identical and correspond one-to-one. Pin 1 of both the first and second constant current sources U7 and U8 are coupled to the DALI bus and used to draw power from the DALI bus to provide a corresponding drain voltage to the drain D of the internal second MOSFET. Pin 2 of the first constant current source U7 is coupled to the source of the internal second MOSFET and to a resistor R external to the first constant current source U7. RX At one end, pin 3 is coupled to resistor R. RX The other end and one end of the emitter of the second optocoupler U2, thereby the signal receiving pin RX of the dimming interface control circuit U1 is coupled to the first constant current source U7 through the second optocoupler U2 and pin 3, and combined with Figure 1 and Figure 7 As shown, M2 in the receiver control module 12 of the dimming interface control circuit U1 is connected in series with the second MOS transistor in the first constant current source U7. Pin 1 of the second constant current source U8 is coupled to the output terminal of the rectifier circuit U0 and one end of the voltage divider resistor Ra. Pin 2 of the second constant current source U8 is coupled to the source of the fourth MOS transistor inside the second constant current source U8 and to the resistor R outside the second constant current source U8. D At one end, pin 3 is coupled to resistor R. D The other end and the drain pin DRAIN of the dimming interface control circuit U1, thereby the drain pin DRAIN of the dimming interface control circuit U1 is coupled to the second constant current source U8 through pin 3, and combined with Figure 1 and Figure 7 As shown, M1 in the transmission control module 11 of the dimming interface control circuit U1 is connected in series with the fourth MOS transistor in the second constant current source U8.

[0088] Please combine Figure 1 and Figure 6 , Figure 7After a surge occurs, the overvoltage protection circuit OVP in the button dimming control module 13 of the dimming interface control circuit U1 will disconnect M1 and M2 inside the dimming interface control circuit U1. Since the second MOSFET in the first constant current source U7 is connected in series at the RX pin and the fourth MOSFET in the second constant current source U8 is connected in series at the DRAIN pin, the second MOSFET in the first constant current source U7 and the fourth MOSFET in the second constant current source U8 can share part of the surge voltage. As a result, M1 and M2 inside the dimming interface control circuit U1 are not easily broken down, and the dimming interface control circuit U1 is not easily disabled, thus enhancing its surge resistance capability.

[0089] It should be understood that the internal circuits of the first constant current source U7 and the second constant current source U8 described above may be the same design or different designs, and the present invention does not make any specific limitation in this regard.

[0090] In other examples of this embodiment, the first constant current source U7 can be omitted, and the second constant current source U8 can be coupled to the DRAIN pin of the dimming interface control circuit U1, which can also enhance the surge protection capability to a certain extent.

[0091] Furthermore, in other examples of this embodiment, at least a portion of the circuitry of the first constant current source U7 and the second constant current source U8 can be integrated into the dimming interface control circuit U1. For example, the second MOS transistor in the first constant current source U7 and the fourth MOS transistor in the second constant current source U8 are both integrated into the dimming interface control circuit U1. Alternatively, both the first constant current source U7 and the second constant current source U8 can be externally located outside the dimming interface control circuit U1.

[0092] In other words, the dimming system provided in this embodiment not only includes the following features of the dimming system in the first embodiment: a DALI bus, at least one DALI control device, and a dimming interface control circuit as described in this invention, which is configured one-to-one with the DALI control device, but also further includes a first constant current source U7 coupled to the signal receiving pin RX of the dimming interface control circuit U1, and / or a second constant current source U8 coupled to the drain pin DRAIN of the dimming interface control circuit U1.

[0093] The dimming interface control circuit and dimming system of this embodiment, which are compatible with multiple dimming methods, not only have the advantages of the solution in the first embodiment, but also have the advantage of high surge resistance.

[0094] The above description is only a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the present invention.

Claims

1. A dimming interface control circuit compatible with multiple dimming modes, characterized in that, Integrated into a single chip and coupled to the DALI bus and DALI control device, the dimming interface control circuit includes: A transmission control module is coupled to the DALI bus and the DALI control device respectively, and is used to upload the signals sent by the DALI control device to the DALI bus; The receiving control module is coupled to the DALI bus and the DALI control device respectively, and is used to send the dimming signal on the DALI bus to the DALI control device. A button dimming control module is coupled to the DALI bus, the transmitting control module, and the receiving control module, respectively. It detects the voltage of the DALI bus during button dimming. When the detected voltage of the DALI bus rises above the internal reference voltage of the button dimming control module, it controls the transmitting and receiving control modules to turn off. When the detected voltage of the DALI bus drops below the internal reference voltage, it controls the receiving control module to turn on, so that the dimming signal on the DALI bus is transmitted to the DALI control device through the receiving control module. The first power supply module is coupled to the energy storage capacitor, the DALI bus, the transmitting control module, the receiving control module, and the key dimming control module, respectively. It is used to charge the energy storage capacitor when the DALI bus is at a high level, provide a first reference voltage to the transmitting control module, a second reference voltage to the receiving control module, and the internal reference voltage to the key dimming control module.

2. The dimming interface control circuit as described in claim 1, characterized in that, The first power supply module includes a power supply switch and a bandgap reference voltage source. One end of the power supply switch is coupled to the DALI bus, and the other end is coupled to the bandgap reference voltage source and the energy storage capacitor. When the power supply switch is turned on and the DALI bus is at a high level, the energy storage capacitor is charged. The bandgap reference voltage source provides the first reference voltage to the transmitting control module, the second reference voltage to the receiving control module, and the internal reference voltage to the key dimming control module.

3. The dimming interface control circuit as described in claim 2, characterized in that, The transmission control module includes a first MOSFET and a first operational amplifier. The gate of the first MOSFET is coupled to the output terminal of the first operational amplifier, the drain of the first MOSFET is coupled to the DALI bus, the source of the first MOSFET is coupled to the second input terminal of the first operational amplifier and the first terminal of the first current-limiting resistor, the second terminal of the first current-limiting resistor is coupled to ground, the first input terminal of the first operational amplifier is coupled to the bandgap reference voltage source to receive the first reference voltage, and the enable terminal of the first operational amplifier is coupled to the DALI control device and the key dimming control module.

4. The dimming interface control circuit as described in claim 3, characterized in that, The transmission control module is coupled to the DALI bus via a second constant current source having a second MOS transistor, the second MOS transistor being coupled in series with the first MOS transistor.

5. The dimming interface control circuit as described in claim 3, characterized in that, The transmission control module is coupled to the DALI control device via a first optocoupler.

6. The dimming interface control circuit as described in any one of claims 2-5, characterized in that, The receiving control module includes a third MOS transistor and a second operational amplifier. The gate of the third MOS transistor is coupled to the output terminal of the second operational amplifier. The drain of the third MOS transistor is coupled to the DALI bus and the DALI control device. The source of the third MOS transistor is coupled to the second input terminal of the second operational amplifier and the first terminal of the second current-limiting resistor. The second terminal of the second current-limiting resistor is coupled to ground. The first input terminal of the second operational amplifier is coupled to the bandgap reference voltage source to receive the second reference voltage. The enable terminal of the second operational amplifier is coupled to the key dimming control module.

7. The dimming interface control circuit as described in claim 6, characterized in that, The receiving control module is coupled to the DALI control device and the DALI bus via a second optocoupler.

8. The dimming interface control circuit as described in claim 7, characterized in that, The second optocoupler is coupled to the DALI bus via a first constant current source having a fourth MOS transistor, which is connected in series with the third MOS transistor.

9. The dimming interface control circuit as described in claim 2, characterized in that, The button dimming control module includes an overvoltage protection circuit. The first input terminal of the overvoltage protection circuit is coupled to the DALI bus to receive the voltage division of the DALI bus. The second input terminal of the overvoltage protection circuit is coupled to the bandgap reference voltage source to receive the internal reference voltage. The output terminal of the overvoltage protection circuit is coupled to the transmitting control module and the receiving control module respectively. When the voltage division is higher than the internal reference voltage, the transmitting control module and the receiving control module are turned off. When the voltage division is lower than the internal reference voltage, the receiving control module is turned on.

10. The dimming interface control circuit as described in claim 1, characterized in that, The chip has: The signal receiving pin is coupled to the receiving control module, the DALI bus, and the DALI control device. The signal transmission pin is coupled to the transmission control module and the DALI control device; A button dimming control pin is coupled to the DALI bus and the button dimming control module; The high-voltage pin is coupled to the DALI bus and the first power supply module; The power supply pin is coupled to the energy storage capacitor and the first power supply module; The sampling pin is coupled to the first current-limiting resistor and the transmission control module; The drain pin is coupled to the DALI bus and the transmit control module; as well as Grounding pin, coupled to ground.

11. The dimming interface control circuit as described in claim 10, characterized in that, The button dimming control pin is coupled to one end of the first voltage divider resistor and one end of the second voltage divider resistor. The other end of the first voltage divider resistor is coupled to the DALI bus, and the other end of the second voltage divider resistor is coupled to ground.

12. A dimming system, characterized in that, include: A DALI bus, at least one DALI control device, and a dimming interface control circuit compatible with multiple dimming modes as described in any one of claims 1-11, each corresponding to one of the DALI control devices, wherein the dimming interface control circuit is coupled to the DALI bus and the DALI control device respectively.

13. The dimming system as described in claim 12, characterized in that, It also includes a DALI host, the DALI bus being coupled to the DALI host.

14. The dimming system as described in claim 12, characterized in that, It also includes a dimming button, one end of which is coupled to the DALI bus, and the other end of which is coupled to the live wire of the AC power supply.

15. The dimming system as described in claim 12, characterized in that, It also includes a rectifier circuit coupled between the DALI bus and the dimming interface control circuit.

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