Dual light source stroboscope controller
By combining the STM32F4 series microcontroller with an isolated 12-bit DAC chip, the shortcomings of the light source controller in terms of accuracy and heat dissipation protection are solved, realizing efficient light source brightness adjustment and synchronous control, and improving imaging quality and efficiency.
Patent Information
- Application Number
- CN202521509270.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-18
- Publication Date
- 2026-08-25
- Estimated Expiration
- 2035-07-18
AI Technical Summary
Existing light source controllers cannot ensure the in-phase or out-of-phase accuracy between two light sources, cannot effectively dissipate heat to protect high-power LED light sources, and have imperfect automatic brightness adjustment functions.
It adopts the STM32F4 series microcontroller chip, is equipped with an Ethernet interface and an RS-485 interface, and combines an isolated 12-bit DAC chip and a strobe driver module to achieve 4096 levels of brightness adjustment and synchronous control. It supports remote configuration and upgrades and has a paper breakage detection function.
It achieves precise control over the brightness and phase difference of the light source, adapts to complex lighting environments, provides flexible lighting solutions, supports remote monitoring and upgrades, and improves imaging quality and efficiency.
Smart Images
Figure CN224684396U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a dual-light source flicker controller and belongs to the field of light source controllers. Background Technology
[0002] Dual-source strobe controllers are typically used in scenarios requiring precise control of lighting conditions, such as industrial inspection, photography, and scientific research. The underlying technologies involve multiple fields, including optics, electronics, and computer science.
[0003] The dual-light source strobe controller is an intelligent device designed to improve the imaging quality and efficiency of industrial vision inspection systems. By precisely controlling the light source brightness and camera shutter operation, it ensures the acquisition of high-quality, clear, and stable images under various complex environmental conditions, thereby supporting efficient and accurate quality inspection and analysis.
[0004] In addition, the dual-light source strobe controller also features remote control and maintenance management functions, assisting managers in controlling equipment and tracking its status. In practical applications, the dual-light source strobe controller is typically used in conjunction with an image acquisition card or a paper defect detection system to acquire images of paper and visualize the data through a platform. The dual-light source strobe controller offers high security, ensuring stable image acquisition and industrial control operation.
[0005] Shortcomings: The light source controllers in the same industry only support a single light source because they cannot ensure the accuracy of the in-phase or out-of-phase relationship between two light sources (switching status, intensity, and phase difference, etc.), or how to effectively dissipate heat to protect high-power light sources such as LEDs from damage. Moreover, the function of automatically adjusting the brightness of the light source is not perfect. This product will provide an algorithm for automatically adjusting the brightness of the light source according to the actual application scenario, so as to realize intelligent light source adjustment. Utility Model Content
[0006] The purpose of this invention is to provide a dual-light source flicker controller that can effectively solve the above-mentioned problems.
[0007] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution: The main control module uses an STM32F4 series microcontroller chip and is equipped with an Ethernet interface and an RS-485 interface. The brightness adjustment module uses an isolated 12-bit DAC chip to achieve 4096 levels of brightness adjustment; A strobe driver module contains two or more strobe drivers for controlling the switching, brightness, and phase difference of two independent light sources respectively; A synchronization control module, wherein the controller supports pulse input for synchronization with an external encoder or camera shutter; The paper breakage detection module automatically turns off the light source and stops the camera from working after detecting a paper breakage signal. The remote control module supports remote configuration and upgrade of controller parameters via Ethernet or RS-485 communication.
[0008] Furthermore, the main control module has a main frequency of 168MHz and has Ethernet communication capabilities for remotely upgrading the control firmware.
[0009] Furthermore, the brightness adjustment module includes a digital-to-analog converter MCP4728 and an isolated communication device for outputting multi-channel analog brightness control signals.
[0010] Furthermore: the strobe drive module is used to control the high-power LED light source, and uses an IRF3205 MOSFET as the drive switch, and is equipped with an isolation drive chip MC33152.
[0011] Furthermore, the synchronization control module supports switching between external encoder input and MCU internal timing control, and has in-phase and out-of-phase signal control functions.
[0012] Furthermore: the paper break detection module determines the paper break event by inputting external IO signals and combining them with client parameter settings, and then shuts down the light source and stops the camera.
[0013] Furthermore, the remote control module enables visualized configuration, real-time monitoring, and remote upgrades of controller parameters through accompanying client software.
[0014] Furthermore, the controller supports different light and shadow combinations by adjusting the phase difference between the main and auxiliary light sources to adapt to the image acquisition needs of complex lighting environments.
[0015] Furthermore, the controller is powered by an external voltage of 24V and has multiple internal power isolation modules to provide different voltage levels such as +12V, +5V, and +3.3V.
[0016] Furthermore, the controller has an automatic light source dimming algorithm that can dynamically adjust the brightness parameters according to the on-site image acquisition effect.
[0017] The beneficial effects are: This light source controller is designed to improve imaging quality and efficiency in the field of visual inspection, featuring a range of advanced functions to meet the diverse needs of industrial scenarios. The system allows manual setting of light source brightness levels to suit the precise control requirements of specific applications; it also supports synchronized operation with light source brightness adjustment, further enhancing imaging performance. The system offers flexible configuration options, enabling it to easily adapt to various complex lighting conditions. Whether in low-light environments or under strong direct sunlight, image quality can be guaranteed by adjusting parameters. Equipped with remote access capabilities, it supports both Ethernet and RS-485 interfaces, allowing users to monitor the operating status of the light source and camera in real time via a companion client, make necessary parameter adjustments, and support remote network upgrades.
[0018] Compared to a single light source, a dual-light source system offers more flexible lighting solutions. By controlling the on / off state, intensity, and phase difference of the two light sources separately, different light and shadow effects can be produced on the illuminated object, thus meeting more complex lighting needs. For example, using combinations of light sources of different colors or wavelengths can enhance the contrast of material surface features, helping to more accurately identify or analyze target objects. Attached Figure Description
[0019] For ease of explanation, this utility model is described in detail below with reference to the specific embodiments and accompanying drawings.
[0020] Figure 1 This is the circuit schematic diagram of this utility model; Figure 2 This is the circuit diagram of the main control module of this utility model; Figure 3 This is the circuit diagram of the flash drive module of this utility model; Figure 4 This is the circuit diagram of the brightness adjustment module of this utility model; Figure 5 This is the circuit diagram of the Ethernet PHY chip of this utility model; Figure 6 This is the circuit diagram of the RJ1 interface module of this utility model; Figure 7 This is the circuit diagram of the isolated transceiver chip of this utility model; Figure 8 This is the circuit diagram of the power module of this utility model; Figure 9 This is a circuit diagram of the control signal isolation chip for the main control chip of this utility model; Figure 10 This is a circuit diagram of the external control signal isolation chip of this utility model; Figure 11 This is a circuit diagram of the digital isolation chip of this utility model; Figure 12This is a circuit diagram of the differential signal isolation driver chip of this utility model; Figure 13 This is a circuit diagram of the optocoupler isolation chip of this utility model; Figure 14 This is the circuit diagram for the protection of the RS-485 communication interface of this utility model; Figure 15 This is a voltage conversion circuit diagram of the present invention; Figure 16 This is a schematic diagram of the light source output of this utility model; Figure 17 This is a schematic diagram of the light source control of this utility model; Figure 18 This is the circuit diagram of the analog switch of this utility model. Detailed Implementation
[0021] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.
[0022] See Figure 1-18 This is one embodiment of the dual-light source strobe controller of this utility model. The dual-light source strobe controller includes multiple functional modules. Each module is connected and cooperates with reasonable electronic components to jointly achieve high-precision and intelligent control of the light source, ensuring that the industrial camera can acquire high-quality images in complex environments.
[0023] like Figure 2 As shown, the core control unit of the controller is an STM32F407ZET6 microcontroller (U1) with a main frequency of 168MHz. It has abundant peripheral resources and can realize functions such as timer control, PWM generation, DAC sampling, I²C and Ethernet communication. It is used to process control commands issued by the client, execute brightness adjustment algorithms, coordinate the timing logic between the light source and the camera, and monitor the working status of each module in real time.
[0024] like Figure 5 As shown, in terms of communication, the main controller connects to the Ethernet PHY chip DM9162 (U2) via the RMII interface, which in turn connects to the RJ1 interface module (HR913550AE) (see...). Figure 6It interconnects with external networks, enabling remote configuration, status feedback, and online upgrades. The network interface area is equipped with matching resistors (R56, R69), TVS diodes (TVS3), and filter capacitors (such as C50, C52, C53) to enhance communication anti-interference capabilities. The controller also features an RS-485 communication interface, connected to the bus via an isolated transceiver CA-IS3098W (U35) (see 7), supporting differential serial communication with external industrial equipment and adapting to various industrial communication scenarios.
[0025] The light source brightness adjustment section uses a four-channel DAC chip MCP4728 (U34) (see 4), which is connected to the main controller via the I²C bus to achieve independent control of the brightness of the main and auxiliary light sources. To improve the bus's anti-interference capability, the I²C signal is electrically isolated by an isolator ISO_1540 (U33). The analog voltage output by the DAC is filtered and then sent to the subsequent driver circuit to provide a high-precision control signal for the light source brightness.
[0026] Regarding the driver module, each light source is driven by a MOSFET IRF3205 (Q6-Q9) and its driver chip MC33152 (U11, U12) (see...). Figure 3 This constitutes a high-speed switching drive unit. This structure supports flicker control for high-power LED light sources. The output circuit is equipped with current-limiting resistors (R71~R74), filter capacitors (C45, C70), and reverse protection diodes (D16~D19) to ensure rapid light source drive response and safe operation under high-frequency flicker conditions.
[0027] To achieve timing synchronization between the light source and the camera, the controller is equipped with encoder input interfaces (ENCODER_A, ENCODER_B) to receive signals from a rotary encoder or external trigger source. The main controller can be connected via a multiplexer TS5A3159A (U24, U25, U26) (see reference). Figure 18 It can switch between different synchronization modes, such as external encoder drive mode and MCU internal control mode, and can set the in-phase or out-of-phase output of the main light source and auxiliary light source according to the PHASE_SEL control signal, and control the synchronization of the encoder or the MCU according to the PHASE_SOR_SEL; such settings can meet the requirements of lighting effects in different scenarios.
[0028] In the paper break detection and input signal isolation section, the controller incorporates an optocoupler isolator HCPL-063L(OPT6) (see [reference]). Figure 13 This provides electrical isolation for external signals, such as paper break signals and start / stop signals. The isolated logic signal is amplified and shaped before being sent to the main controller for judgment. Once a paper break is detected, the controller can immediately turn off the light source, stop taking pictures, and link other modules to enter a safe standby state.
[0029] The power module adopts a graded voltage regulation architecture. The system is powered by DC24V, first through the high-efficiency DC-DC chip LMR14030(U4) (see...). Figure 8 The voltage is stepped down from 24V to 5V, and then passed through an AZ1117 series linear regulator (U3 outputs 5V, U13 outputs 3.3V) (see...). Figure 15 The power supply provides stable power to the communication module, logic devices, and MCU. The matching filter inductor (L1), capacitors (C133, C135) and TVS diode (D6) further improve the power quality and surge protection.
[0030] To avoid interference between different voltage domains, ADuM1200 (U28) and ADuM1400 (U21, U23) are used (see reference). Figure 9 Figure 10 The digital isolator enables secure signal isolation between different functional areas; at the same time, it combines with the SN74AHC1G00 (U32) logic gate circuit to judge and shape key control signals, ensuring that signals can still be accurately transmitted and responded to under complex operating conditions.
[0031] In terms of parameter configuration and status storage, the controller uses an MB85RC64V (U18) non-volatile FRAM memory to save user configuration parameters such as brightness level and strobe mode via the I²C bus, which will not be lost even when power is off. For the indication system, multiple LEDs (such as D31 and D33) are used to indicate power, communication, and operating status, respectively, facilitating on-site debugging and maintenance.
[0032] Introduction to the main hardware used in this controller: The dual-light source strobe controller operates on 24V power and uses a high-performance STM32F4 series MCU with a 168MHz main frequency. It communicates with clients via 100Mbps Ethernet or RS-485. Pulse input utilizes an encoder or other input methods to synchronize the light source and camera timing. It supports 4096 levels of light source brightness adjustment, enabling precise control of light source brightness and camera shutter operation. It also supports paper break detection; upon paper breakage, the dual-light source strobe controller can shut off the light source, stop camera operation, and perform other related controls.
[0033] The isolated transceiver chip CA-IS3098W (U35) is an isolated RS-485 transceiver. Its main function is to realize RS-485 communication between the main control MCU and external devices and provide electrical isolation protection. CA-IS3098WU (35) is used to convert the serial communication signal (TTL level) of the main control MCU into a differential signal that conforms to the RS-485 standard. At the same time, through the internal opto-isolation structure, it electrically isolates the MCU side from the external communication bus.
[0034] This circuit also includes a protection circuit for the RS-485 communication interface. Its core function is to prevent damage to the communication chip from surges, overvoltage, or short circuits on the bus (485A / 485B). Specifically, a TBU-CA065-200WH (high-speed fuse-type protector) is used, which instantly cuts off the path when the current exceeds 200mA, protecting the downstream circuitry. A MOV-10D201K (varistor) absorbs high-voltage surges (such as lightning strikes) and suppresses transient overvoltages. A TVS4 (SM712) bidirectional TVS diode clamps abnormal voltages (such as ESD) between the 485A / 485B lines, ensuring the signal level remains within a safe range. This circuit, through multi-level protection (overcurrent, overvoltage, impedance matching), ensures the stability and anti-interference capability of RS-485 communication in industrial environments.
[0035] The four-channel DAC chip MCP4728 (U34) converts digital brightness control commands sent by the main control MCU via the I²C interface into analog voltage signals, thereby enabling fine-tuning of the brightness of the dual light sources. Each channel independently outputs a control voltage, corresponding to different branches of the main and auxiliary light sources. After filtering and amplification, the voltage drives the light sources, achieving a maximum of 4096 levels of brightness adjustment. This ensures uniform and stable illumination during image acquisition, meeting the requirements of high-precision visual inspection.
[0036] The ISO_1540 (U33) isolator is a dual-channel, bidirectional I²C bus isolator used in this circuit to achieve electrical isolation between the main control MCU and external I²C devices (such as the MCP4728DAC chip for brightness adjustment). This chip can achieve bidirectional isolated transmission of SCL and SDA signals while maintaining the integrity of the I²C protocol, preventing communication abnormalities caused by ground potential differences or interference signals between different power domains, thereby improving the system's reliability and anti-interference capability in industrial environments.
[0037] The multi-channel analog switch TS5A3159A (U24, U25, U26) is used. U24, U25, and U26 are all TS5A3159A single-pole double-throw (SPDT) analog switch chips. U24 selectively connects one of two different signal sources to the target circuit through the control pin, which is used to realize the switching control of the signal path by the main control system in different working modes.
[0038] The U25 receives control signals from the main control MCU and selects a specific light source control signal (such as the main light source or the auxiliary light source) to be connected to the strobe drive circuit according to the settings, thereby realizing the start and stop of the light source.
[0039] The U26 receives control signals from the main control MCU and, according to the set operating mode, switches a specific input signal (such as from an external trigger signal or internal system control logic) to the camera's trigger input. When it is necessary to enable or stop the camera from taking pictures, the U26 achieves precise control over the camera's shooting behavior by switching the conduction path.
[0040] The TLP185 optocoupler isolator (OPT5, OPT2) consists of two optocoupler-isolated MOSFET driver circuits. Both OPT5 and OPT2 are primarily used for the safe switching of 24V high-power loads (such as LED light sources), while simultaneously providing electrical isolation between the low-voltage control signal (3V3D) and the high-voltage load (24V_2). They utilize MOSFETs for efficient switching of high-current loads (such as LED light sources) and support high-frequency flicker control. A combination of diodes and capacitors suppresses transient voltage / current, improving system stability.
[0041] This power supply regulation architecture consists of the DC-DC chip LMR14030 (U4) and digital isolators ADuM1200 (U28) and ADuM1400 (U21, U23). U21 primarily forwards the encoder's A-phase output to three channels; U23 forwards the camera shutter output to four channels; and U28 typically handles dedicated isolation tasks for some high-speed input or output signals, such as for encoder feedback signals or external pulse inputs, ensuring accurate and reliable timing. (U21 forwards the encoder's A-phase input to three channels, and U23 forwards the camera shutter output to four channels.)
[0042] The FRAM U18 is an MB85RC64V chip used to store the controller's configuration parameters and operating status data, such as light source brightness levels, flicker modes, synchronization settings, and paper breakage response strategies. This chip communicates with the main control MCU via the I²C bus, ensuring data retention even after system power failure. Compared to traditional EEPROM, FRAM offers higher read / write speeds and stronger erase / write durability, making it suitable for scenarios requiring frequently updated parameter storage. It is one of the key components for implementing the controller's power-off memory and self-recovery functions.
[0043] In this circuit, the CA-IS3115AW (U30, U31) is a high-speed digital isolator chip, primarily used for electrical isolation between the main control system and external high-speed signal lines (such as synchronization control, start / stop signals, etc.). It effectively prevents potential difference interference between different power grounds through opto-isolation technology, improving the system's anti-interference capability and operational stability in complex industrial environments. Simultaneously, this chip features low latency and high common-mode rejection, ensuring reliable transmission of critical control signals after isolation, making it one of the key components for achieving safe and high-speed communication in the system.
[0044] The CA-IS1311G (U36) is a high-speed, low-power differential signal isolation driver used for isolating and driving high-speed signals. The isolation driver circuit primarily uses opto-isolation of the differential control signals output from the main control MCU and drives them to external interfaces to achieve highly reliable output of synchronization pulse signals. This chip integrates a high-speed digital isolator, supporting high-speed signal transmission and possessing strong common-mode rejection (CMR) capability, effectively preventing high-speed signals from being distorted by electromagnetic interference or ground potential differences in industrial environments. Through the CA-IS1311G's isolation and enhanced driving capabilities, the controller can safely and stably transmit critical trigger signals to high-speed response devices (industrial cameras, encoders, or host systems), thereby ensuring the overall accuracy and safety of the system.
[0045] The optocoupler isolation circuit, composed of the HCPL-063L (OPT6) chip and TLP185 (OPT2, OPT5), is used to electrically isolate high-speed control signals (such as synchronous triggering, start-stop control, etc.) output by the main control MCU before safely transmitting them to external devices, thus achieving paper break detection. Through this optocoupler, the system effectively isolates electrical interference between the logic control circuit and the high-power drive circuit or external interface, improving the anti-interference capability of the control signal and the stability of system operation. It is suitable for applications in complex industrial environments with high requirements for synchronization and safety.
[0046] Client: Connect the Ethernet or 485 interface of the control board of the dual-light source strobe controller to the computer, open the client, click Test Connection, and the user can remotely manage the installed dual-light source strobe controller.
[0047] Light source brightness adjustment: The dual light source strobe controller allows users to independently adjust the light source brightness according to the on-site conditions, supporting a 4096-level adjustment range, which can meet most camera photography needs.
[0048] Paper break detection: The dual-light source strobe controller can automatically detect paper breaks. When a paper break occurs, the system can automatically shut down the light source, camera operation, and other related controls. Users can also manually configure the paper break signal mode through the client to meet different paper break types on the production line.
[0049] Parameter configuration: After the user modifies and saves the parameters, the parameter settings will take effect after clicking to restart the control board. After a successful restart, the control board will run according to the new parameters.
[0050] Remote system upgrade: The light source control system can remotely upgrade the control board via Ethernet.
[0051] This dual-source flicker controller uses a high-performance ARM Cortex-M4 processor with a 168MHz clock speed as its main control core. The dimming section employs an isolated 12-bit DAC chip, enabling 4096 levels of brightness adjustment. The flicker section utilizes a dual-channel flicker driver, meeting the requirement of low-current digital signals driving large capacitive loads with high-voltage slew rates. Its low input current ensures compatibility with CMOS / LSTTL logic, enabling fast output switching unaffected by input transition times.
[0052] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.
Claims
1. A dual-light source strobe controller, characterized in that: include: The main control module uses an STM32F4 series microcontroller chip and is equipped with an Ethernet interface and an RS-485 interface. The brightness adjustment module uses an isolated 12-bit DAC chip to achieve 4096 levels of brightness adjustment; A strobe driver module, comprising two or more strobe drivers, is used to control the switching of two independent light sources respectively; A synchronization control module, wherein the controller supports pulse input for synchronization with an external encoder or camera shutter; The paper breakage detection module automatically turns off the light source and stops the camera from working after detecting a paper breakage signal. The remote control module supports remote configuration and upgrade of controller parameters via Ethernet or RS-485 communication.
2. The dual-light source flicker controller according to claim 1, characterized in that: The main control module has a main frequency of 168MHz and has Ethernet communication capabilities for remotely upgrading the control firmware.
3. The dual-light source flicker controller according to claim 2, characterized in that: The brightness adjustment module includes a digital-to-analog converter MCP4728 and an isolated communication device for outputting multi-channel analog brightness control signals.
4. The dual-light source flicker controller according to claim 3, characterized in that: The strobe drive module is used to control high-power LED light sources. It uses an IRF3205 MOSFET as a drive switch and is equipped with an isolation drive chip MC33152.
5. The dual-light source flicker controller according to claim 4, characterized in that: The synchronization control module supports switching between external encoder input and MCU internal timing control, and has in-phase and out-of-phase signal control functions.
6. The dual-light source flicker controller according to claim 1, characterized in that: The paper break detection module determines the paper break event by inputting external IO signals and combining them with client parameter settings, and then shuts down the light source and stops the camera.
7. The dual-light source flicker controller according to claim 1, characterized in that: The remote control module enables visualized configuration, real-time monitoring, and remote upgrades of controller parameters through accompanying client software.
8. The dual-light source flicker controller according to claim 1, characterized in that: The controller supports different light and shadow combinations by adjusting the phase difference between the main and auxiliary light sources to meet the image acquisition needs of complex lighting environments.
9. The dual-light source flicker controller according to claim 1, characterized in that: The controller is powered by an external voltage of 24V and has multiple internal power isolation modules to provide different voltage levels of +12V, +5V, and +3.3V.
10. The dual-light source flicker controller according to claim 1, characterized in that: The controller has an automatic light source dimming algorithm that can dynamically adjust the brightness parameters according to the on-site image acquisition effect.