CN112996191B

CN112996191B - High-frequency dimming circuit, high-frequency dimming method, power supply device and light-emitting device

Info

Publication number: CN112996191B
Application number: CN202110237992.XA
Authority: CN
Inventors: 不公告发明人
Original assignee: Wuxi Lead Intelligent Equipment Co Ltd
Current assignee: Wuxi Lead Intelligent Equipment Co Ltd
Priority date: 2021-03-04
Filing date: 2021-03-04
Publication date: 2022-06-14
Anticipated expiration: 2041-03-04
Also published as: CN112996191A

Abstract

The application relates to a high-frequency dimming circuit, a high-frequency dimming method, a power supply device and a light-emitting device, wherein a linear amplification driving module is used for providing equal driving current for each lamp bead; the multi-stage conversion module is used for providing reference voltages with preset levels for the linear amplification driving module, wherein the reference voltages with different levels are different; the trigger circuit is used for generating a pulse type trigger signal with a first preset frequency; the main control circuit is used for generating a pulse type voltage signal with a second preset frequency according to the obtained light source control data packet and the pulse type trigger signal so as to control the multistage conversion module to provide the reference voltage with the second preset frequency for the linear amplification driving module, and the linear amplification driving module is used for providing a driving current with the second preset frequency for each lamp bead. The application provides a high frequency technology of adjusting luminance possesses that the electric current is established the time and is short, the adjustting of the lighteness scope is big, current regulation precision is high, the luminous effect of lamp pearl is even and advantage such as low power dissipation.

Description

High-frequency dimming circuit, high-frequency dimming method, power supply device and light-emitting device

Technical Field

The present invention relates to the field of electronic circuits, and in particular, to a high-frequency dimming circuit, a high-frequency dimming method, a high-frequency dimming power supply device, and a light emitting device.

Background

The light source that traditional visual scene was used adopts the constant voltage mode drive lamp pearl mostly, changes the voltage at lamp pearl both ends through control and adjusts the luminance of lamp pearl. If a constant voltage driving mode is adopted to simultaneously control a plurality of lamp beads, because the lamp beads have the factors of poor consistency, large influence by temperature, large change of volt-ampere characteristics influenced by environment and the like, the conditions of inconsistent voltage, large change of internal resistance and the like can occur on each lamp bead, the brightness of the lamp beads in a row or a column is inconsistent directly, and the expected brightness effect can not be achieved.

In addition, the range from the starting voltage of the light emission of the common white light lamp bead to the maximum working voltage is 2V-3.5V, the adjustable range of the voltage is narrow, and the precision requirement of light and dark adjustment of a light source cannot be met, so that the application scene of the traditional constant-voltage multi-lamp bead light source is limited, and the constant-voltage multi-lamp bead light source is difficult to apply to a high-speed scene. When the light source needs to be wholly bright or wholly twinkle, the light emitting establishment time of the lamp bead is long, and the interference is serious; the power consumption is high, the temperature rise is obvious, the voltage fluctuation is large, the service life is short, and the like.

Disclosure of Invention

Accordingly, it is necessary to provide a high-frequency dimming circuit, a method, a power supply device and a light emitting device using constant current driving, which have the advantages of short current establishing time, wide brightness adjusting range, high current adjusting precision, uniform light emitting effect of the lamp beads, low power consumption, and the like.

In order to achieve the above objects and other objects, a first aspect of the present application provides a high frequency dimming circuit for dimming an array light source, the array light source includes lamp beads arranged in an array, the circuit includes:

the linear amplification driving module is used for providing equal driving current for each lamp bead;

the multi-stage conversion module is connected with the linear amplification driving module and is used for providing reference voltages with preset levels for the linear amplification driving module, wherein the reference voltages in different levels are different;

the trigger circuit is connected with the multistage conversion module and is used for generating a pulse type trigger signal with a first preset frequency;

the main control circuit is connected with the multistage conversion module and the trigger circuit, and is configured to acquire a light source control data packet and the pulse type trigger signal, and generate a pulse type voltage signal with a second preset frequency according to the light source control data packet and the pulse type trigger signal, so as to control the multistage conversion module to provide the reference voltage with the second preset frequency for the linear amplification driving module, so that the linear amplification driving module provides the driving current with the second preset frequency for each lamp bead.

In the high-frequency dimming circuit in the above embodiment, the linear amplification driving module is arranged to provide equal driving current for each lamp bead, so as to ensure the uniformity of current control for each lamp bead, and make each lamp bead have uniform light-emitting effect; the linear amplification driving module is provided with reference voltages with preset levels through a multistage conversion module, wherein the reference voltages with different levels are different, so that the magnitude of driving current is adjusted in multiple different levels through the linear amplification driving module, the brightness of lamp beads is adjusted in multiple different levels, and the multistage dimming control of the array light source in a wide range is realized; the pulse type trigger signal of the first preset frequency is generated through the trigger circuit, so that the main control circuit generates a pulse type voltage signal of the second preset frequency according to the received light source control data packet and the pulse type trigger signal, the multi-stage conversion module is controlled to provide the reference voltage of the second preset frequency for the linear amplification driving module, the linear amplification driving module provides the driving current of the second preset frequency for each lamp bead, multi-level high-frequency control of the array type light source in an ultra-large range is achieved, the requirement of the array type light source for high-frequency flicker in the ultra-wide frequency band is met, and meanwhile, high current regulation precision and low power consumption are guaranteed.

In one embodiment, the master control circuit includes:

the control module is connected with the trigger circuit and used for acquiring the light source control data packet and generating a light source parameter control signal and light source brightness data according to the light source control data packet, so that the trigger circuit generates the pulse type trigger signal according to the received light source parameter control signal;

and the field programmable gate array is connected with the control module, the multistage conversion module and the trigger circuit and is used for receiving the light source brightness data and the pulse type trigger signal and generating the pulse type voltage signal according to the light source brightness data and the pulse type trigger signal.

In the high-frequency dimming circuit in the above embodiment, the field programmable gate array is arranged in the main control circuit to transmit light source brightness data, such as the number of levels of light source brightness control, to the multi-level conversion module at a high speed, and the pulse type trigger signal is used to control the multi-level conversion module at a high speed to provide the reference voltage with the second preset frequency for the linear amplification driving module, so that the linear amplification driving module provides the driving current with the second preset frequency for each lamp bead at a high speed, thereby effectively reducing the light-emitting establishment time of the array type light source lamp bead and realizing multi-level high-frequency control of the array type light source in an ultra-large range.

In one embodiment, the multi-stage conversion module comprises:

a reference chip for outputting a reference voltage value;

and the digital-to-analog conversion control chip is connected with the reference chip, the field programmable gate array and the linear amplification driving module, and is used for receiving the reference voltage value and the pulse type voltage signal and generating the reference voltage with a second preset frequency according to the reference voltage value and the pulse type voltage signal.

In one embodiment, the linear amplification driving module includes:

the controllable constant current driving unit is used for providing equal driving current for each lamp bead;

an operational amplifier unit configured to: the first input end is connected with the first output end of the multistage conversion module, the second input end is connected with the output of the controllable constant current driving unit, and the output end is connected with the control end of the controllable constant current driving unit.

In one embodiment, each of the lamp beads in the array light source is connected in parallel, and the controllable constant current driving unit includes:

a first controllable switch unit configured to: the first end is connected with a first direct current power supply through the array light source, the second end is connected with the second input end of the operational amplifier unit through a first current limiting resistor and is grounded through a second current limiting resistor, and the control end is connected with the output end of the operational amplifier unit through a third current limiting resistor.

In one embodiment, the high frequency dimming circuit further includes an overcurrent protection unit, and the overcurrent protection unit includes:

the controllable sampling current unit is connected with the main control circuit and is used for providing an overcurrent protection trigger signal for the main control circuit;

a comparison unit configured to: the first input end is connected with the second end of the first controllable switch unit through a fourth current-limiting resistor to receive the feedback voltage provided by the controllable constant-current driving unit, the second input end is connected with the second output end of the multistage conversion module through a fifth current-limiting resistor to receive the reference voltage provided by the multistage conversion module, and the output end is connected with the second input end of the comparison unit through a first capacitor and is connected with the control end of the controllable sampling current unit;

when the feedback voltage is greater than the reference voltage, the comparison unit provides a comparison result signal to the controllable sampling current unit, so that the controllable sampling current unit provides an overcurrent protection trigger signal to the main control circuit according to the comparison result signal.

In one embodiment, the controllable sampling current unit includes:

a second controllable switching unit configured to: the first end of the first bias resistor is connected with the second direct current power supply through a sixth current limiting resistor and is connected with the main control circuit, the second end of the first bias resistor is grounded, and the control end of the first bias resistor is connected with the output end of the comparison unit through a seventh current limiting resistor and is grounded through the first bias resistor.

In one embodiment, the trigger circuit includes:

an encoder for outputting a differential signal;

and the differential-to-single-ended circuit is connected with the encoder and the main control circuit and is used for receiving the differential signal and generating a pulse type trigger signal of the first preset frequency according to the differential signal.

In one embodiment, the differential-to-single-ended circuit includes:

a differential to single-ended chip configured to: the first input end is connected with the first output end of the encoder through an eighth current limiting resistor and is grounded through a second capacitor, the second input end is connected with the second output end of the encoder through a ninth current limiting resistor and is grounded through a third capacitor, and the output end is connected with the main control circuit through a tenth current limiting resistor;

wherein the first output terminal of the encoder is connected to the second output terminal of the encoder via a balancing resistor.

A second aspect of the present application provides a power supply apparatus comprising a high frequency dimming circuit as described in any of the embodiments of the present application.

A third aspect of the present application provides a lighting device comprising a high-frequency dimming circuit and a light source as described in any of the embodiments of the present application.

A fourth aspect of the present application provides a high-frequency dimming method for dimming an array-type light source, where the array-type light source includes lamp beads arranged in an array, and the method includes:

the linear amplification driving module is controlled to provide equal driving current for each lamp bead;

controlling a multi-stage conversion module to provide reference voltages with preset levels for the linear amplification driving module, wherein the reference voltages with different levels are different;

controlling a trigger circuit to generate a pulse type trigger signal with a first preset frequency;

and acquiring a light source control data packet and the pulse type trigger signal, and generating a pulse type voltage signal with a second preset frequency according to the light source control data packet and the pulse type trigger signal to control the multistage conversion module to provide the reference voltage with the second preset frequency for the linear amplification driving module, so that the linear amplification driving module provides the driving current with the second preset frequency for each lamp bead.

In the high-frequency dimming method in the above embodiment, the linear amplification driving module is controlled to provide equal driving current for each lamp bead, so as to ensure the uniformity of current control for each lamp bead, and ensure that each lamp bead has uniform light emitting effect; the method comprises the steps that reference voltages with preset levels are provided for a linear amplification driving module by controlling a multistage conversion module, wherein the reference voltages with different levels are different, so that the magnitude of driving current is adjusted in a plurality of different levels through the linear amplification driving module, the brightness of lamp beads is adjusted in the plurality of different levels, and multistage dimming control of an array type light source in a wide range is realized; the control trigger circuit is used for generating a pulse type trigger signal with a first preset frequency, so that the main control circuit generates a pulse type voltage signal with a second preset frequency according to a received light source control data packet and the pulse type trigger signal, the multistage conversion module is controlled to provide the reference voltage with the second preset frequency for the linear amplification driving module, the linear amplification driving module is used for providing the driving current with the second preset frequency for each lamp bead, multi-level high-frequency control of the array type light source in an ultra-large range is achieved, the requirement of the array type light source for high-frequency flicker in an ultra-wide frequency band is met, and meanwhile, high current regulation precision and low power consumption are guaranteed.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain drawings of other embodiments based on these drawings without any creative effort.

Fig. 1 is a schematic circuit diagram of a high-frequency dimming circuit provided in a first embodiment of the present application;

fig. 2 is a schematic circuit diagram of a high-frequency dimming circuit provided in a second embodiment of the present application;

fig. 3 is a schematic circuit diagram of a high-frequency dimming circuit provided in a third embodiment of the present application;

fig. 4 is a schematic circuit diagram of a high-frequency dimming circuit provided in a fourth embodiment of the present application;

fig. 5 is a schematic circuit diagram of a part of a high-frequency dimming circuit provided in a fifth embodiment of the present application;

fig. 6 is a schematic circuit diagram of a part of a high-frequency dimming circuit provided in a sixth embodiment of the present application;

fig. 7 is a schematic circuit diagram of a part of a high-frequency dimming circuit provided in a seventh embodiment of the present application;

fig. 8 is a schematic circuit diagram of a part of a high frequency dimming circuit provided in an eighth embodiment of the present application;

fig. 9 is a schematic structural diagram of a power supply device provided in a ninth embodiment of the present application;

fig. 10 is a schematic structural diagram of a light-emitting device provided in a tenth embodiment of the present application;

fig. 11 is a flowchart illustrating a high-frequency dimming method according to an eleventh embodiment of the present application.

Detailed Description

To facilitate an understanding of the present application, the present application will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present application are illustrated in the accompanying drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Where the terms "comprising," "having," and "including" are used herein, another element may be added unless an explicit limitation is used, such as "only," "consisting of … …," etc. Unless mentioned to the contrary, terms in the singular may include the plural and are not to be construed as being one in number.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the present application.

In this application, unless otherwise expressly stated or limited, the terms "connected" and "connecting" are used broadly and encompass, for example, direct connection, indirect connection via an intermediary, communication between two elements, or interaction between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

Referring to fig. 1, in an embodiment of the present application, a high-frequency dimming circuit 100 is provided for dimming an array light source 101, where the array light source 101 includes lamp beads arranged in an array, the high-frequency dimming circuit 100 includes a linear amplification driving module 10, a multi-stage conversion module 20, a trigger circuit 30 and a main control circuit 40, and the linear amplification driving module 10 is configured to provide equal driving current for each of the lamp beads; the multistage conversion module 20 is connected to the linear amplification driving module 10, and is configured to provide reference voltages of a preset number of levels for the linear amplification driving module 10, where the reference voltages at different levels are different; the trigger circuit 30 is connected to the multi-stage conversion module 20, and is configured to generate a pulse type trigger signal at a first preset frequency; the main control circuit 40 is connected to both the multistage conversion module 20 and the trigger circuit 30, and is configured to obtain a light source control data packet and the pulse type trigger signal, and generate a pulse type voltage signal with a second preset frequency according to the light source control data packet and the pulse type trigger signal, so as to control the multistage conversion module 20 to provide the reference voltage with the second preset frequency for the linear amplification driving module 10, so that the linear amplification driving module 10 provides the driving current with the second preset frequency for each lamp bead.

Specifically, please refer to fig. 1, a linear amplification driving module 10 is arranged to provide equal driving currents for the lamp beads, so as to ensure the uniformity of current control for the lamp beads, and make the light emitting effect of the lamp beads uniform; the reference voltages with preset levels are provided for the linear amplification driving module 10 through the multistage conversion module 20, wherein the reference voltages with different levels are different, so that the magnitude of the driving current is adjusted in multiple different levels through the linear amplification driving module 10, the brightness of the lamp beads is adjusted in multiple different levels, and the multistage dimming control of the array light source 101 in a wide range is realized; the trigger circuit 30 generates a pulse type trigger signal with a first preset frequency, so that the main control circuit 40 generates a pulse type voltage signal with a second preset frequency according to the received light source control data packet and the pulse type trigger signal, and controls the multistage conversion module 20 to provide the reference voltage with the second preset frequency for the linear amplification driving module 10, so that the linear amplification driving module 10 provides the driving current with the second preset frequency for each lamp bead, thereby realizing multi-level high-frequency control of the array type light source 101 in an ultra-large range, meeting the requirement of the array type light source 101 on high-frequency flicker in an ultra-wide frequency band, and ensuring high current regulation precision and low power consumption.

Further, referring to fig. 2, in an embodiment of the present application, the main control circuit 40 includes a control module 41 and a Field Programmable Gate Array (FPGA) 42, where the control module 41 is connected to the trigger circuit 30, and is configured to obtain the light source control data packet, and generate a light source parameter control signal and light source brightness data according to the light source control data packet, so that the trigger circuit 30 generates the pulse type trigger signal according to the received light source parameter control signal; the field programmable gate array 42 is connected to the control module 41, the multi-stage conversion module 20, and the trigger circuit 30, and is configured to receive the light source luminance data and the pulse type trigger signal, and generate the pulse type voltage signal according to the light source luminance data and the pulse type trigger signal.

Specifically, referring to fig. 2, the field programmable gate array 42 is disposed in the main control circuit 40 to transmit light source brightness data, such as the number of levels of light source brightness control, to the multi-level conversion module 20 at a high speed, and to control the multi-level conversion module 20 at the high speed to provide the reference voltage with the second preset frequency to the linear amplification driving module 10, so that the linear amplification driving module 10 provides the driving current with the second preset frequency to each lamp bead at the high speed, thereby effectively reducing the setup time of light emission of the array light source lamp bead, and implementing multi-level high-frequency control of the array light source 101 in an ultra-large range.

Further, referring to fig. 3, in an embodiment of the present application, the multi-stage conversion module 20 includes a reference chip 21 and a digital-to-analog conversion control chip 22, where the reference chip 21 is configured to output a reference voltage value; the digital-to-analog conversion control chip 22 is connected to the reference chip 21, the field programmable gate array 42 and the linear amplification driving module 10, and is configured to receive the reference voltage value and the pulse voltage signal, and generate the reference voltage with a second preset frequency according to the reference voltage value and the pulse voltage signal, so that the linear amplification driving module 10 provides a driving current with the second preset frequency for each lamp bead, so as to implement multi-level high-frequency control of the array light source 101 in an ultra-large range, meet a requirement of the array light source 101 for high-frequency flicker in an ultra-wide band, and ensure high current regulation precision and low power consumption.

Further, referring to fig. 4, in an embodiment of the present application, the linear amplification driving module 10 includes a controllable constant current driving unit 11 and an operational amplifier unit 12, where the controllable constant current driving unit 11 is configured to provide equal driving current for each of the lamp beads; the op-amp unit 12 is configured to: the first input end is connected with the first output end of the multistage conversion module 20, the second input end is connected with the output of the controllable constant current driving unit 11, and the output end is connected with the control end of the controllable constant current driving unit 11.

Further, referring to fig. 5, in an embodiment of the present application, each of the lamp beads in the array light source 101 is connected in parallel, the controllable constant current driving unit 11 includes a first controllable switch unit Q1, and the first controllable switch unit Q1 is configured to: the first end is connected to the first dc power source via the array light source 101, the second end is connected to the second input end of the operational amplifier unit U1 via the first current limiting resistor R1 and is grounded via the second current limiting resistor R2, and the control end is connected to the output end of the operational amplifier unit U1 via the third current limiting resistor R3.

Further, referring to fig. 6, in an embodiment of the present application, the high-frequency dimming circuit further includes an overcurrent protection unit 50, where the overcurrent protection unit 50 includes a controllable sampling current unit 51 and a comparison unit 52, and the controllable sampling current unit 51 is connected to the main control circuit and is configured to provide an overcurrent protection trigger signal to the main control circuit; the comparison unit 52 is configured to: the first input terminal is connected to the second terminal of the first controllable switch unit Q1 via a fourth current-limiting resistor R4 to receive the feedback voltage provided by the controllable constant-current driving unit 11, the second input terminal is connected to the second output terminal of the multilevel converter module 20 via a fifth current-limiting resistor R5 to receive the reference voltage provided by the multilevel converter module 20, and the output terminal is connected to the second input terminal of the comparing unit 52 via a first capacitor C1 and to the control terminal of the controllable sampling current unit 51; when the feedback voltage is greater than the reference voltage, the comparing unit 52 provides a comparison result signal to the controllable sampling current unit 51, so that the controllable sampling current unit 51 provides an overcurrent protection trigger signal to the main control circuit according to the comparison result signal.

Further, with continuing reference to fig. 6, in an embodiment of the present application, the controllable sampling current unit 51 comprises a second controllable switching unit Q2, the second controllable switching unit Q2 being configured to: the first terminal is connected to the second dc power supply through a sixth current limiting resistor R6 and to the main control circuit, the second terminal is grounded, and the control terminal is connected to the output terminal of the comparing unit 52 through a seventh current limiting resistor R7 and to the ground through a first bias resistor R8.

Specifically, with continued reference to fig. 6, the sampled voltage output from the resistor R2 is coupled to a first input terminal of the comparing unit 52, and a second input terminal of the comparing unit 52 is coupled to a given reference voltage value. When the sampling voltage is greater than the set reference voltage value, it is determined that the sampling current is too large, the output end of the comparison unit 52 generates a high level signal, a low level is output to the FPGA chip through the output end of the second controllable switch unit Q2, and when the IO port of the FPGA chip detects the low level, the voltage supply to the DAC chip is immediately stopped, so that the linear amplification driving module 10 is controlled to stop working, the lamp bead is prevented from being damaged, and the purpose of overcurrent protection is achieved; otherwise, when the sampling voltage is smaller than the set reference voltage value, the current of the lamp bead is judged to work in a normal range, the IO port of the FPGA chip detects a high level, and the system is judged to normally run.

Further, referring to fig. 7, in an embodiment of the present application, the reference chip 21 includes a REF3012AIDBZR chip, configured to output a reference voltage value to the digital-to-analog conversion control chip 22; the digital-to-analog conversion control chip 22 comprises a 12-bit DAC128S085 cimtxopp chip (DAC), the output end of the reference chip 21 is connected with the ninth end of the DAC chip, the SPI interface of the DAC chip is used for FPGA connection, the first output end of the DAC chip is used for connection with the first input end of the operational amplifier unit 12, and the second output end of the DAC chip is used for connection with the second input end of the comparison unit 52. The auxiliary circuits of the DAC128S085 cimtxopb chip and the REF3012AIDBZR chip are all of the common knowledge in the art, and are not described herein again. The FPGA chip drives a 12-bit DAC (DAC128S085CIMTX) through SPI interfaces, namely DIN1, SCLK1 and SYNC1 signals, the DAC has 8-path output, 2.5V reference is generated by a REF3012AIDBZR reference chip to the DAC, therefore, the DAC channel output can generate 0-2.5V voltage change, and the DAC has 12 digital bits, namely 1024 levels, and the output analog quantity 2.5V also has 1024 levels. The FPGA switches the DAC channel output through the fastest 10us, so that the output voltage is changed by 10 us. Therefore, the lamp bead works under the constant current state by adopting 12-bit DAC and high-precision operational amplifier combined with the first controllable switch unit Q1. A high-speed FPGA chip is added, the linear amplification driving module 10 is used for controlling the lamp beads in parallel, for example, the LED lamp beads change in current of 0-1024 levels, and the array light source 101 meets the stroboscopic effect of 0-100Khz by combining high-bandwidth operational amplification; and the control circuit has the advantages of short current establishing time, ultrahigh adjusting precision, uniform light emitting effect of the lamp beads, low power consumption and the like.

Further, referring to fig. 8, in an embodiment of the present application, the triggering circuit includes an encoder 31 and a differential-to-single-ended circuit 32, where the encoder 31 is configured to output a differential signal; the differential-to-single-ended circuit 32 is connected to the encoder 31 and the main control circuit, and is configured to receive the differential signal and generate a pulse type trigger signal of the first preset frequency according to the differential signal.

Further, with continuing reference to fig. 8, in an embodiment of the present application, the differential-to-single-ended circuit 32 includes a differential-to-single-ended chip 321, and the differential-to-single-ended chip 321 is configured to: the first input end is connected with the first output end of the encoder 31 through an eighth current limiting resistor R9 and is grounded through a second capacitor C2, the second input end is connected with the second output end of the encoder 31 through a ninth current limiting resistor R10 and is grounded through a third capacitor C3, and the output end is connected with the main control circuit through a tenth current limiting resistor R11; the first output terminal of the encoder 31 is connected to the second output terminal of the encoder 31 via a balancing resistor R11.

Specifically, please refer to fig. 8, the first output terminal INA + and the second output terminal INA-of the encoder 31 output differential signals, when the differential signal passes through the AM26LS32ACDR to be converted into a single-ended chip, the differential signal is converted into a single-ended pulse signal, the single-ended pulse signal is output to the FPGA by the differential conversion chip, the FPGA performs pulse voltage output on the 12-bit DAC chip through edge detection and judgment, and the linear amplification driving module 10 controls the array light source 101 to strobe.

Further, referring to fig. 9, in an embodiment of the present application, a power supply apparatus 200 is provided, which includes the high frequency dimming circuit 100 as described in any of the embodiments of the present application. The lamp beads are driven by a constant current of a linear amplification driving module 10; the FPGA chip can switch the reference voltage output by the 12-bit DAC at a high speed through the SPI interface, utilizes the current fed back by the operational amplifier to close-loop control the MOS tube and finally drive the array light source 101, and therefore the effect of switching the brightness stroboscopic effect of the array light source 101 by 10us at the fastest speed is achieved. By utilizing the characteristics of the 12-bit DAC, 0-1024 level current stepping is met, and the change of stepless dimming of the light source is realized. Through increasing overcurrent protection circuit, perfect improvement because external disturbance and environmental change lead to the lamp pearl damage phenomenon. The light-emitting device adopting the high-frequency dimming circuit 100 has the advantages of short current establishing time, large brightness adjusting range, high current adjusting precision, uniform light-emitting effect of lamp beads, low power consumption and the like.

Further, referring to fig. 10, in an embodiment of the present application, a light emitting device 300 is provided, which includes the high frequency dimming circuit 100 and the array light source 101 as described in any of the embodiments of the present application. The linear amplification driving module 10 is arranged to provide equal driving current for each lamp bead so as to ensure the uniformity of current control of each lamp bead and ensure the uniform light-emitting effect of each lamp bead; providing reference voltages with preset levels for the linear amplification driving module 10 through the multi-level conversion module 20, wherein the reference voltages with different levels are different, so as to adjust the magnitude of the driving current in multiple different levels through the linear amplification driving module 10, thereby realizing multi-level dimming control of the array light source 101 in a wide range; the trigger circuit 30 generates a pulse type trigger signal with a first preset frequency, so that the main control circuit 40 generates a pulse type voltage signal with a second preset frequency according to the received light source control data packet and the pulse type trigger signal, and controls the multistage conversion module 20 to provide the reference voltage with the second preset frequency for the linear amplification driving module 10, so that the linear amplification driving module 10 provides the driving current with the second preset frequency for each lamp bead, thereby realizing multi-level high-frequency control of the array type light source 101 in an ultra-large range, meeting the requirement of the array type light source 101 on high-frequency flicker in an ultra-wide frequency band, and ensuring high current regulation precision and low power consumption.

Specifically, referring to fig. 10, the linear amplification driving module 10 may be controlled to provide a working voltage for the light source, and then the amplification level selecting module 33 is controlled to operate in the first working mode, so that the first-stage feedback amplification module 31 operates, and then the current detecting module 20 is used to detect the working current of the light source; if the amplitude of the working current is smaller than the preset threshold, controlling the amplification level selection module 33 to work in a second working mode to control the secondary feedback amplification module 32 to work, otherwise, continuously controlling the primary feedback amplification module 31 to work; further, the linear amplification driving module 10 is controlled to stop supplying power to the light source 102, the output voltage value of the first digital-to-analog conversion unit 41 is determined to be equal to the voltage value output by the multi-stage feedback amplification module 30 according to the working current of the light source, the first digital-to-analog conversion unit 41 is set to provide a reference voltage for the second digital-to-analog conversion unit 42, and the multi-stage constant current driving module 40 is controlled to provide constant current driving for the light source 102; gradually adjusting the working voltage of the second digital-to-analog conversion unit 42 until the output voltage thereof reaches a constant value, and recording the currently measured working voltage of the light source 102 as a rated voltage; the output voltage value of the first digital-to-analog conversion unit 41 is adjusted again, so that the reference voltage provided by the first digital-to-analog conversion unit meets the requirement of the rated voltage; the output voltage of the second dac unit 42 is adjusted to provide 1024 levels of adjustable current to meet the brightness requirement of the light source 102.

Further, referring to fig. 11, in an embodiment of the present application, a high-frequency dimming method 400 is provided for dimming an array light source, where the array light source includes beads arranged in an array, and the method includes:

step 42, controlling a linear amplification driving module to provide equal driving current for each lamp bead;

step 44, controlling a multistage conversion module to provide reference voltages with preset levels for the linear amplification driving module, wherein the reference voltages at different levels are different;

step 46, controlling the trigger circuit to generate a pulse type trigger signal with a first preset frequency;

and 48, acquiring a light source control data packet and the pulse type trigger signal, and generating a pulse type voltage signal with a second preset frequency according to the light source control data packet and the pulse type trigger signal to control the multistage conversion module to provide the reference voltage with the second preset frequency for the linear amplification driving module, so that the linear amplification driving module provides the driving current with the second preset frequency for each lamp bead.

Specifically, please refer to fig. 11, the linear amplification driving module is controlled to provide equal driving currents for the lamp beads, so as to ensure the uniformity of current control for the lamp beads, and thus the light-emitting effect of each lamp bead is uniform; the method comprises the steps that reference voltages with preset levels are provided for a linear amplification driving module by controlling a multistage conversion module, wherein the reference voltages with different levels are different, so that the magnitude of driving current is adjusted in a plurality of different levels through the linear amplification driving module, the brightness of lamp beads is adjusted in the plurality of different levels, and multistage dimming control of an array type light source in a wide range is realized; the control trigger circuit is used for generating a pulse type trigger signal with a first preset frequency, so that the main control circuit generates a pulse type voltage signal with a second preset frequency according to a received light source control data packet and the pulse type trigger signal, the multistage conversion module is controlled to provide a reference voltage with the second preset frequency for the linear amplification driving module, the linear amplification driving module provides a driving current with the second preset frequency for each lamp bead, multi-level high-frequency control of the array type light source in an ultra-large range is achieved, the requirement of the array type light source for high-frequency flicker in the ultra-wide frequency band is met, and high current regulation precision and low power consumption are guaranteed.

More specifically, in an embodiment of the present application, the control module may be an upper computer, and the upper computer starts and obtains a light source control data packet, and generates a light source parameter control signal and light source brightness data according to the light source control data packet, so that the trigger circuit generates the pulse type trigger signal according to the received light source parameter control signal; the FPGA receives the light source brightness data and the pulse type trigger signal, generates the pulse type voltage signal according to the light source brightness data and the pulse type trigger signal, and controls the multistage conversion module to provide the reference voltage with a second preset frequency for the linear amplification driving module, so that the linear amplification driving module provides the driving current with the second preset frequency for each lamp bead. The array light source is controlled in a multi-level high frequency mode within an ultra-large range, the requirement of the array light source for high-frequency flicker within an ultra-wide frequency band is met, and meanwhile high current regulation precision and low power consumption are guaranteed.

For specific limitations of the high-frequency dimming method in the above embodiment, reference may be made to the above limitations of the high-frequency dimming circuit, which is not described herein again.

It should be understood that the steps described are not to be performed in the exact order recited, and that the steps may be performed in other orders, unless explicitly stated otherwise. Moreover, at least some of the steps described may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, and the order of performing the sub-steps or stages is not necessarily sequential, but may be performed alternately or in alternation with other steps or at least some of the sub-steps or stages of other steps.

It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by hardware instructions of a computer program, which can be stored in a non-volatile computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in the embodiments provided herein may include non-volatile and/or volatile memory, among others.

It should be noted that the above-mentioned embodiments are only for illustrative purposes and are not meant to limit the present invention.

The embodiments in the present specification are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The high-frequency dimming circuit (100) is used for dimming an array type light source (101), wherein the array type light source (101) comprises lamp beads arranged in an array, and the circuit comprises:

the linear amplification driving module (10) is used for providing equal driving current for each lamp bead;

the multi-stage conversion module (20) is connected with the linear amplification driving module (10) and is used for providing reference voltages with preset levels for the linear amplification driving module (10), wherein the reference voltages with different levels are different;

the trigger circuit (30) is connected with the multistage conversion module (20) and is used for generating a pulse type trigger signal with a first preset frequency;

the main control circuit (40) is connected to the multistage conversion module (20) and the trigger circuit (30) and configured to acquire a light source control data packet and the pulse type trigger signal, and generate a pulse type voltage signal with a second preset frequency according to the light source control data packet and the pulse type trigger signal to control the multistage conversion module (20) to provide the reference voltage with the second preset frequency for the linear amplification driving module (10), so that the linear amplification driving module (10) provides the driving current with the second preset frequency for each lamp bead.

2. A high frequency dimming circuit (100) as claimed in claim 1, wherein the master control circuit (40) comprises:

a control module (41) connected to the trigger circuit (30) and configured to acquire the light source control data packet, and generate a light source parameter control signal and light source brightness data according to the light source control data packet, so that the trigger circuit (30) generates the pulse type trigger signal according to the received light source parameter control signal;

and the field programmable gate array (42) is connected with the control module (41), the multistage conversion module (20) and the trigger circuit (30) and is used for receiving the light source brightness data and the pulse type trigger signal and generating the pulse type voltage signal according to the light source brightness data and the pulse type trigger signal.

3. A high frequency dimming circuit (100) as claimed in claim 2, wherein the multi-level conversion module (20) comprises:

a reference chip (21) for outputting a reference voltage value;

and the digital-to-analog conversion control chip (22) is connected with the reference chip (21), the field programmable gate array (42) and the linear amplification driving module (10) and is used for receiving the reference voltage value and the pulse type voltage signal and generating the reference voltage with a second preset frequency according to the reference voltage value and the pulse type voltage signal.

4. A high frequency dimming circuit (100) according to any of claims 1-3, wherein the linear amplification driving module (10) comprises:

the controllable constant current driving unit (11) is used for providing equal driving current for each lamp bead;

an operational amplifier unit (12) configured to: the first input end of the multi-stage conversion module (20) is connected with the first output end of the multi-stage conversion module, the second input end of the multi-stage conversion module is connected with the output end of the controllable constant current driving unit (11), and the output end of the multi-stage conversion module is connected with the control end of the controllable constant current driving unit (11).

5. The high-frequency dimming circuit (100) according to claim 4, wherein each of the lamp beads in the array light source (101) is connected in parallel, and the controllable constant current driving unit (11) comprises:

a first controllable switching unit (Q1) configured to: the first end is connected with a first direct current power supply through the array light source (101), the second end is connected with the second input end of the operational amplifier unit (U1) through a first current limiting resistor (R1) and is grounded through a second current limiting resistor (R2), and the control end is connected with the output end of the operational amplifier unit (U1) through a third current limiting resistor (R3).

6. The high frequency dimming circuit (100) of claim 5, further comprising an over-current protection unit (50), the over-current protection unit (50) comprising:

the controllable sampling current unit (51) is connected with the main control circuit (40) and is used for providing an overcurrent protection trigger signal for the main control circuit (40);

a comparison unit (52) configured to: a first input terminal is connected with a second terminal of the first controllable switch unit (Q1) through a fourth current limiting resistor (R4) to receive the feedback voltage provided by the controllable constant current driving unit (11), a second input terminal is connected with a second output terminal of the multistage conversion module (20) through a fifth current limiting resistor (R5) to receive the reference voltage provided by the multistage conversion module (20), and an output terminal is connected with a second input terminal of the comparison unit (52) through a first capacitor (C1) and is connected with a control terminal of the controllable sampling current unit (51);

wherein the comparison unit (52) provides a comparison result signal to the controllable sampling current unit (51) when the feedback voltage is greater than the reference voltage, so that the controllable sampling current unit (51) provides an overcurrent protection trigger signal to the main control circuit (40) according to the comparison result signal.

7. High frequency dimming circuit (100) according to claim 6, wherein the controllable sampling current unit (51) comprises:

a second controllable switching unit (Q2) configured to: the first end is connected with the second direct current power supply through a sixth current limiting resistor (R6) and is connected with the main control circuit (40), the second end is grounded, and the control end is connected with the output end of the comparison unit (52) through a seventh current limiting resistor (R7) and is grounded through a first bias resistor (R8).

8. A high frequency dimming circuit (100) according to any of claims 1-3, wherein the trigger circuit (30) comprises an encoder (31) and a differential to single ended circuit (32), the encoder (31) is configured to output a differential signal; the differential-to-single-ended circuit (32) is connected with the encoder (31) and the main control circuit (40) and is used for receiving the differential signal and generating a pulse type trigger signal with the first preset frequency according to the differential signal.

9. The high frequency dimming circuit (100) of claim 8, wherein the differential to single ended circuit (32) comprises:

a differential to single-ended chip (321) configured to: the first input end is connected with the first output end of the encoder (31) through an eighth current limiting resistor (R9) and is connected with the ground through a second capacitor (C2), the second input end is connected with the second output end of the encoder (31) through a ninth current limiting resistor (R10) and is connected with the ground through a third capacitor (C3), and the output end is connected with the main control circuit (40) through a tenth current limiting resistor (R12);

wherein a first output of the encoder (31) is connected to a second output of the encoder (31) via a balancing resistor (R11).

10. A power supply device (200), comprising:

a high frequency dimming circuit (100) as claimed in any of claims 1-9.

11. A light-emitting device (300), comprising:

a high frequency dimming circuit (100) as claimed in any one of claims 1 to 9; and

an array light source (101).

12. A high frequency dimming method (400) for dimming an array light source (101), the array light source (101) comprising beads arranged in an array, the method comprising:

controlling a linear amplification driving module (10) to provide equal driving current for each lamp bead;

controlling a multi-stage conversion module (20) to provide reference voltages with preset levels for the linear amplification driving module (10), wherein the reference voltages with different levels are different;

controlling a trigger circuit (30) to generate a pulse type trigger signal with a first preset frequency;

and acquiring a light source control data packet and the pulse type trigger signal, and generating a pulse type voltage signal with a second preset frequency according to the light source control data packet and the pulse type trigger signal to control the multistage conversion module (20) to provide the reference voltage with the second preset frequency for the linear amplification driving module (10), so that the linear amplification driving module (10) provides the driving current with the second preset frequency for each lamp bead.