LTC3783PWM LED drivers and boost, flyback, and SEPIC type controllers
peculiarity
- True Color PWMTM 提供了恒定的彩色和 3000:1 的调光比
- 用于实现高功率 LED 的 PWM 调光控制的全集成化负载 FET 驱动器
- 从模拟输入进行 100:1 的调光
- 宽 FB 电压范围：0V 至 1.23V
- 恒定电流或恒定电压调节
- 低停机电流：IQ = 20µA
- 精度为 1% 的 1.23V 内部电压基准
- 具有 100mV 迟滞的 2% RUN 引脚门限
- 可利用一个外部电阻器来设置工作频率 (范围为 20kHz 至 1MHz)
- 可与一个频率高达 1.3fOSC 的外部时钟同步
- 内部 7V 低压差稳压器
- 可编程输出过压保护
- 可编程软起动
- 可在一种无检测电阻 (No RSENSETM) 模式中使用 (VDS
- 16 引脚 DFN 和 TSSOP 封装
description
The LTC®3783 is a current-mode LED driver and boost, flyback, and SEPIC-type controller used to drive an N-channel power MOSFET and an N-channel load PWM switch. When an external load switch is employed, the PWMIN input not only drives PWMOUT, but also enables the controller GATE switch and error amplifier operation, allowing the controller to store load current information when PWMIN is low. This feature (patent pending) enables extremely fast, true PWM load switching operation without transient overvoltage or undervoltage issues; The 3000:1 LED dimming ratio can be achieved digitally, avoiding the color shift phenomenon common with LED current dimming. The FBP pin provides simulated dimming of the load current, resulting in an effective dimming ratio of 100:1 compared to PWM alone.
In applications where the output load current must return to the VIN, an optional constant current/constant voltage regulation is used to control the output (or input) current or output voltage and provide a limit value for another parameter. ILIM offers a 10:1 analog dimming ratio.
For low- to medium-power applications, the no-sense resistor mode takes advantage of the on-resistance of the power MOSFET and eliminates the need for a current-sense resistor to maximize efficiency.
The IC can be set to a frequency range of 20kHz to 1MHz via an external resistor and can be synchronized with an external clock using the SYNC pin.
LTC3783 is available in 16-pin DFN and TSSOP packages.
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- 高电压 LED 数组
- 电信电源
- 42V 汽车系统
- 24V 工业控制
- IP 电话电源