LM3445
- TRIAC Dim Decoder Circuit for LED Dimming
- Application Voltage Range 80 VAC to 277 VAC
- Capable of Controlling LED Currents Greater
Than 1 A - Adjustable Switching Frequency
- Low Quiescent Current
- Adaptive Programmable Off-Time Allows for
Constant Ripple Current - Thermal Shutdown
- No 120-Hz Flicker
- Low Profile 10-Pin VSSOP Package or 14-Pin
SOIC - Patented Drive Architecture
The LM3445 is an adaptive constant off-time AC/DC buck (step-down) constant current controller designed to be compatible with TRIAC dimmers. The LM3445 provides a constant current for illuminating high power LEDs and includes a TRIAC dim decoder. The dim decoder allows wide range LED dimming using standard TRIAC dimmers. The high frequency capable architecture allows the use of small external passive components. The LM3445 includes a bleeder circuit to ensure proper TRIAC operation by allowing current flow while the line voltage is low to enable proper firing of the TRIAC. A passive PFC circuit ensures good power factor by drawing current directly from the line for most of the cycle, and provides a constant positive voltage to the buck regulator. Additional features include thermal shutdown, current limit and VCC under-voltage lockout.
技术文档
| 顶层文档 | 类型 | 标题 | 格式选项 | 下载最新的英语版本 | 日期 | |
|---|---|---|---|---|---|---|
| * | 数据表 | LM3445 TRIAC Dimmable Offline LED Driver 数据表 (Rev. M) | PDF | HTML | 2015-11-30 | ||
| 白皮书 | 常见 LED 功能和 LED 驱动器设计注意事项 | 英语版 | 2020-9-21 | |||
| 选择指南 | 电源管理指南 2018 | 2018-7-31 | ||||
| EVM 用户指南 | 120Vac Valley Fill Buck Triac Dimmable LED Driver | 2015-5-12 | ||||
| 应用手册 | AN-1656 Design Challenges of Switching LED Drivers (Rev. A) | 2013-5-3 | ||||
| EVM 用户指南 | AN-1935 LM3445 Off-Line TRIAC Dimmer LED Driver Demo Board (Rev. I) | 2013-5-1 | ||||
| 用户指南 | AN-2061 LM3445 A19 Edison Retrofit Evaluation Board (Rev. C) | 2013-5-1 | ||||
| 应用手册 | AN-2034 LM3445 -120VAC, 8W Isolated Flyback LED Driver (Rev. C) | 2013-5-1 | ||||
| 用户指南 | AN-1995 LM3445 208-277V AC Non-Isolated Evaluation PCB (Rev. B) | 2013-5-1 | ||||
| 应用手册 | An Improved Line Regulation Solution Used in LM3444/5 Non-Isolated LED Lighting | 2012-10-25 | ||||
| 用户指南 | 230 Vac Off-line Triac Dimmer Retrofit with 6 LEDs Reference Design User Guide | 2012-1-27 | ||||
| 应用手册 | AN-2069 LM3445 - 230VAC, 6W- 15W Isolated Flyback LED Driver (Rev. B) | 2010-11-23 |
设计与开发
如需其他信息或资源，请点击以下任一标题进入详情页面查看（如有）。
LM3445EVM-695 — LM3445 120Vac 谷填降压型可控硅调光 LED 驱动器评估模块
LM3445EVM-695 采用德州仪器 (TI) 的 LM3445 集成电路实现调光解决方案。LM3445 是一款自适应恒定关断时间交流/直流降压恒流控制器，具有内置相位调光解码器。内部低功耗数字控制器会持续分析线路周期的形状和对称性。然后生成模拟电流基准，供电源转换器级用于调节输出电流。使用为优化调光器兼容性、功率因数和 THD 而开发的控制算法来操控模拟基准。使用恒定关断时间控制，该解决方案可实现较少的器件数和高效率，并固有地带来开关频率变化。这种变化会产生仿真展频效应，从而降低转换器 EMI 特征，并允许使用较小的输入滤波器。
PMP30439 — 采用 230V 输入和 180V 输出的 200 mA 恒流 LED 驱动器参考设计
| 封装 | 引脚 | CAD 符号、封装和 3D 模型 |
|---|---|---|
| VSSOP (DGS) | 10 | Ultra Librarian |
| SOIC (D) | 14 | Ultra Librarian |