CXLE87206 integrates a rainbow jumping pattern program, MCU digital interface, data latch, and twelve high-voltage drive circuits internally, with dual working modes of external control and internal control. In external control mode, the chip receives controller instructions through a single wire interface to achieve precise brightness, color, and cascade control; In internal control mode, when a signal interruption is detected for more than 60ms, it automatically switches to the built-in rainbow jump program, ensuring that the system can maintain dynamic display even without external control signals, greatly improving the system's robustness and scene adaptability.
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[ CXLE87206 ]"
CXLE87206: Twelve channel intelligent dual-mode LED driver chip, empowering outdoor display and lighting systems
The reliability, flexibility, and environmental adaptability of driver chips are crucial in applications such as outdoor LED displays, colorful light strips, guardrail tubes, and building lighting. CXLE87206, as a twelve channel LED constant voltage drive control dedicated circuit that integrates external and internal control, provides engineers with a highly integrated and reliable solution with its high voltage tolerance, intelligent dual-mode switching, high-precision dimming, and powerful cascading capability. This article will comprehensively analyze the technical characteristics, working modes, communication protocols, and typical applications of the chip, helping users build high-performance LED control systems.
1、 Chip Overview
CXLE87206 integrates a rainbow jumping pattern program, MCU digital interface, data latch, and twelve high-voltage drive circuits internally, with dual working modes of external control and internal control. In external control mode, the chip receives controller instructions through a single wire interface to achieve precise brightness, color, and cascade control; In internal control mode, when a signal interruption is detected for more than 60ms, it automatically switches to the built-in rainbow jump program, ensuring that the system can maintain dynamic display even without external control signals, greatly improving the system's robustness and scene adaptability.
2、 Core functional features
• Twelve channel high voltage outputSupports four sets of RGB outputs, with a total of 12 PWM controls and a voltage resistance of 32V per channel, suitable for outdoor high-voltage working environments.
• Intelligent switching between external control and internal controlSupports precise dimming and pattern control from external controllers, automatically switches to the built-in rainbow pattern when disconnected (with a cycle of approximately 13.5 seconds).
• High precision brightness adjustment256 level PWM regulation, equivalent to 1024 levels at low brightness, achieving smooth and delicate brightness changes.
• High voltage compatibility and wide voltage inputBoth the data and driver ports have a withstand voltage of 32V, and the VDD external series resistor supports a wide voltage input of 6-32V.
• Single line serial cascadeCapable of automatic signal shaping, cascading signals without attenuation, supporting long-distance and multi node deployment.
• High refresh rate supportAt a refresh rate of 30fps, it supports cascading 1024 pixel points, meeting the refresh requirements of most outdoor dot matrix systems.
• High communication speedThe data transmission rate is 800Kbps, the response is fast, and the system has good real-time performance.
3、 Electrical characteristics and packaging
• Working voltage range6V~32V (configured through external resistor)
• Communication and driver port withstand voltage：32V
• PWM scanning frequency：≥900Hz
• package form：SOP16， Suitable for high-density PCB layout
• Operating Temperature-40 ℃~+85 ℃, suitable for harsh outdoor environments
3.1. Packaging and Pin Function;
3.2. Input/output equivalent circuit
3.3. Limit parameter
3.4. Recommended working conditions
3.5 Electrical Characteristics
3.6 Switch characteristics
3.7. temporal characteristic
3.8 Data transmission and forwarding
The process of data transmission and forwarding during chip cascading: the controller sends data (D1), and when chip 1 receives the first 96 bits, it has not yet forwarded the data (D2). Then the controller continues to send data, and chip 1 receives the second 96 bits. Since chip 1 already stores the first 96 bits, chip 1 forwards the second 96 bits through DO, and chip 2 receives the data forwarded by chip 1 (D2). At this time, chip 2 has not yet forwarded the data (D3); The controller continues to send data, and chip 1 forwards the received third 96 bit to chip 2. Since chip 2 already has a 96 bit, chip 2 forwards the third 96 bit (D3). Chip 3 receives the third 96 bit. If the controller sends a RESET high-level signal greater than 150 ms, all chips will reset and decode the received 96 bit data to control the RGB port output, completing a data refresh cycle. The chip returns to the receiving preparation state.
4、 Detailed explanation of working mode
4.1. External control mode (controlled mode)
The chip receives 96 bit data (24 bits per RGB group) through DIN pins, analyzes it, and outputs the corresponding PWM waveform. Support single line cascading, the controller only needs to send data packets from each node followed by a RESET signal to refresh the entire system.
4.2. Internal control mode (autonomous mode)
When there is no external control signal, it automatically switches and executes the built-in seven color jump program (seven color combination cycle), with a weekly cycle of about 13.5 seconds. This function effectively avoids the display black screen caused by signal interruption, and is suitable for guardrail pipes, landscape lighting, and other needs; Self running” The scenario of ability.
4.3. Basic description
This chip adopts a single line communication method and sends signals using normalization code. After power on reset, the chip receives data from the DIN terminal and completes 4× After 24 bits, the DO port starts forwarding data that continues to be sent from the DIN end, providing input data for the next cascaded chip. Before forwarding data, the DO port remains at a high level. If DIN inputs a RESET reset signal, the chip will reset successfully based on the received 4× The 24 bit data output corresponds to the PWM duty cycle waveform, and the chip waits for new data to be received again, starting from 4× after receiving; After 24 bit data, the data is forwarded through the DO port, and the original output of the RGB port remains unchanged until the chip receives a RESET signal.
The chip adopts automatic shaping and forwarding technology, which can avoid signal attenuation and distortion when transmitting over long distances with many points, so that the number of cascades of the chip is not limited by signal transmission, only limited by screen refresh speed requirements.
4.4. data structure
Send data in RGB order, starting with high bits first.
When DIN has no data input for more than 60ms, CXLE87206 will enter internal control mode. When in internal control mode, the pattern effect is rainbow jumping,
The time to complete a pattern cycle is approximately 13.5 seconds.
The process of changing internal control patterns is as follows:
5、 Typical Application Design Guidelines
5.1. System cascading and refresh rate configuration
Taking 800Kbps communication rate as an example:
• Each pixel (RGB) requires 24 bits of data, with a transmission time of 30 seconds.
• When the system contains 1000 pixels, the single refresh time is 30ms and the refresh rate is 33Hz, which meets most dynamic display requirements.
The data refresh time is calculated based on how many pixels are cascaded in a system. A set of RGB is usually one pixel, and one CXLE87206 chip controls four pixels. For example, when the refresh rate is 30 frames per second, the calculation method for the number of points that the chip can control is:
(1) 30 frames per second is equivalent to the time occupied by each frame being T1=1s÷ 30=0.033333s=33333μ s；
(2) The data bit period is 1.25μ s,. And each pixel should receive 24 bits of data, so the time required to transmit each pixel is T2=24× 1.25μs=30μ s；
(3) The number of points that can be controlled is: N=T1/T2=33333μ s÷ 30μs=1111。
Based on the above calculation of the number of points, and after removing the chip and wire transmission delay, the conservative conclusion is that when the refresh rate is 30 frames per second
Cascade control 1024 pixels.
The following is a table of the highest data refresh rate corresponding to cascading points:
5.2. Power supply design and resistor selection
The chip VDD requires an external series resistor to adapt to an input voltage of 6-32V. Formula for calculating resistance value:
R = (DC - 5.0V) / 10mA
The commonly used configurations are as follows:
• 6V power supply: 100Ω
• 9V power supply: 400Ω
• 12V power supply: 700Ω
The resistance values of R1-R12 can be adjusted according to the number of LEDs connected in series with the OUT port. It is recommended to connect a 100 ohm resistor to RI and RO for signal isolation to prevent damage to the next level chip from affecting the previous level.
CXLE87206 can be configured for DC6-32V voltage supply, but different power resistors should be configured according to different input voltages. Set flow through
The current of VDD pin is calculated as 10mA, and the resistance of VDD series connection is R=(DC-5.0V)/10mA (DC is the power supply voltage). The list of resistance values under common power supply voltages is as follows:
5.3. Signal link protection
5.4. Expansion plan
To drive high-power LEDs, PNP transistors or P-MOS transistors can be connected externally to the OUT port to achieve current expansion, meeting the needs of high brightness or high-power lighting.
In practical applications, it is often necessary to drive high-power or more LED lights. In order to obtain a larger driving current, the following method can be used for current expansion: choose a suitable PNP transistor or P-channel MOS transistor (field-effect transistor) according to the power of the LED light.
6、 Application scenarios
• Outdoor full-color LED display screen
• Guardrail tubes and colorful light strips
• Architectural facade lighting and landscape lighting
• Stage lighting and performance equipment
• Advertising signage and decorative lighting system
7、 Conclusion
CXLE87206 provides a highly reliable and flexible driving solution for outdoor LED display and lighting systems with its twelve channel high-voltage output, intelligent dual-mode switching, high-precision dimming, and powerful cascading capability. Whether it is a performance scene that requires precise control or a landscape project that requires autonomous operation, this chip can achieve complex light effect control in a single-chip form, significantly reducing system complexity and maintenance costs.
JTMIC（jtm-ic.com） As the official technical partner of this chip, we provide one-stop services from sample application, design support to bulk supply. For detailed data manuals, design guidelines, or technical assistance, please visit our official website or contact our professional technical team
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