CXLE86135E is a highly integrated single-segment high-voltage linear constant-current LED driver chip, which integrates high-voltage rectifier tube and JFET high-voltage power supply circuit, and can be directly connected to high-voltage AC power supply without external rectifier bridge. The chip supports a maximum output power of 9W and is compatible with mainstream silicon controlled dimmers. During the dimming process, the LED brightness is smooth and uniform, without flicker or jitter.
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[ CXLE86135 ]"
CXLE86135E: high performance linear thyristor dimming LED driver chip depth analysis
In the LED lighting drive scheme, the linear constant current architecture is gradually becoming the mainstream choice for small and medium power lighting applications because of its simple structure, no magnetic components and high reliability. As a high-voltage and high-precision linear thyristor dimming LED driver chip introduced by JTM-IC, CXLE86135E is widely used in bulb lamps, downlights, fluorescent lamps and other scenes with its high integration, no electrolytic capacitor design and excellent dimming compatibility. This article will comprehensively introduce the technical characteristics, working principle, design points and typical applications of the chip, and help engineers to build high-performance, long-life LED lighting systems.
1. Product Overview
CXLE86135E is a highly integrated single-segment high-voltage linear constant-current LED driver chip, which integrates high-voltage rectifier tube and JFET high-voltage power supply circuit, and can be directly connected to high-voltage AC power supply without external rectifier bridge. The chip supports a maximum output power of 9W and is compatible with mainstream silicon controlled dimmers. During the dimming process, the LED brightness is smooth and uniform, without flicker or jitter.
The chip uses a unique constant current control technology to achieve an output current accuracy better than ± 5%, and the current value can be flexibly set by an external sampling resistor. Due to its linear architecture, the system does not require transformers, inductors and high-voltage electrolytic capacitors, which greatly simplifies the peripheral circuit and is particularly suitable for the manufacture of mass, low-cost LED lighting products.
The CXLE86135E adopts heat dissipation enhanced ESOP-8 package, which has good thermal performance and power tolerance, combined with internal over-voltage and over-temperature protection mechanism to ensure stable and reliable operation of the system under various abnormal conditions.
2. core features and benefits
1. Highly integrated and minimalist peripheral
The chip integrates high-voltage rectifier tube and JFET power supply circuit, without external rectifier bridge, VCC capacitor and start-up resistor, the system only needs a small number of resistance and capacitance components and sampling resistor to work, greatly reducing BOM cost and PCB area.
2. No electrolytic capacitor design
The linear architecture eliminates the need for high-voltage electrolytic capacitors, which solves the problems of short life and poor temperature resistance of electrolytic capacitors in traditional switching power supplies, significantly improves the service life and reliability of the system, and is especially suitable for high-temperature working environments.
3. Excellent SCR dimming compatibility
The chip supports leading-edge phase cutting (TRIAC) dimming, wide dimming range, no flicker, compatible with most SCR dimmers on the market, to meet the needs of home, commercial places in the optical tuning.
4. High precision constant current output
Using accurate current sampling and control technology, the output current accuracy reaches ± 5%, supports dual parallel output, and can flexibly set the current value through an external resistor to adapt to different LED lamp bead combinations.
5. Comprehensive protection mechanisms
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Overtemperature Regulation (OTR): When the chip junction temperature exceeds 140 ℃, the output current is automatically reduced to prevent overheating damage.
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Overvoltage protection: The internal integrated overvoltage protection circuit ensures the safe operation of the system under open circuit and abnormal high voltage conditions.
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ESD ProtectionWith 2000V HBM ESD capability, improve the production and use of antistatic ability.
3. key parameters and package information
The CXLE86135E adopts ESOP-8 package, which has good heat dissipation performance and welding process adaptability. The main electrical parameters are as follows:
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Output current range：
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220V ± 20% input: 35mA @ VOUT = 250V
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110V ± 20% Input: 50mA @ VOUT = 130V
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Starting voltage: 5V typical
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Output withstand voltage：500V
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Maximum power：9W
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Thermal resistance (junction-ambient):145℃/W
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over-temperature regulating point: 140 ℃
4. working principle and system design
1. Power supply and start-up mechanism
After the system is powered on, the OUT pin provides the operating voltage to the chip through the internal JFET. When the OUT voltage exceeds 5V, the chip starts to work normally. In thyristor dimming applications, the OUT1 and OUT2 dual structure can provide a discharge circuit for the capacitor in the dimming circuit to ensure that the dimming process is stable and does not flicker.
2. Constant current control mechanism
The chip realizes high-precision constant current control by detecting the CS1/CS2 pin voltage. The output current is set by an external sampling resistor RCS, and its calculation formula is:
ILED = VREF /RCSwhere VREF is the internal reference voltage. The CS pin is equipped with a filter circuit to effectively suppress the on-noise interference.
3. Lamp string voltage matching
As a linear drive scheme, the CXLE86135E requires the LED string voltage to be close to the peak value of the input AC voltage. Taking 220VAC application as an example, if 18V high-voltage LED lamp beads are used, 14-15 lamps are usually connected in series to ensure that the system works in an efficient range.
4. Heat dissipation design and power improvement
In the linear architecture, the chip itself bears the voltage difference and power consumption, and the thermal design is very important. The following measures are recommended to improve output capacity:
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Using aluminum substrate PCB
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Increase the copper-clad area at the bottom of the chip
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Optimization of heat dissipation structure of lamps and lanterns
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Multi-chip parallel use
5. PCB Design Guide
In order to ensure system stability and thermal performance, PCB layout should pay attention to the following points:
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Heat dissipation design: The heat sink at the bottom of the chip should be connected to the underlying copper foil or aluminum substrate through multiple vias to make full use of the PCB for heat dissipation.
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Sampling Resistor Layout: The power ground wire of CS resistor should be as short and thick as possible, and star grounding method should be adopted to avoid noise interference.
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High voltage isolation: The OUT pin is a high-voltage node and should be far away from the low-voltage signal line to prevent coupling interference.
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current path optimizationPower loop area should be as small as possible to reduce EMI radiation and voltage ringing.
6. typical application scenarios
CXLE86135E widely used in the following LED lighting products:
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LED bulb lamp (A19, PAR lamp, etc.)
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LED downlights and spotlights
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T8/T5 LED fluorescent tube
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Candle lights and decorative lighting
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Other non-isolated linear drive LED lamps
Its simple architecture, good dimming compatibility and high reliability make it an ideal alternative to traditional resistance-capacitance step-down and simple linear solutions.
7. epilogue
With its high integration, no electrolytic capacitor design, excellent thyristor dimming performance and high-precision constant current output, the CXLE86135E provides a simple, reliable and low-cost drive solution for LED intelligent lighting systems. Whether upgrading traditional lamps or developing new smart dimming products, the chip can help engineers find the best balance between performance, cost and reliability.
For CXLE86135E samples, technical documentation or application support, please visitJTM-IC official websiteOr contact our technical support team. Jiatem Electronics (JTM-IC) is committed to providing global customers with high-quality, high-reliability power management integrated circuit products and solutions to help your lighting products stand out in the market competition.
