LTC3207

peculiarity

• 低噪声、多模式充电泵 (1x、1.5x、2x) 提供了高达91% 的效率
• 转换速率受限的开关操作降低了传导噪声和辐射噪声 (EMI)
• 高达 600mA 的总输出电流
• 具 64 级线性亮度控制能力的 12 个 28mA 通用电流源
• 具 16 级线性亮度控制能力和两秒高电流安全定时器的 425mA CAM (相机) LED 电流源
• 采用两线式 I2C^TM 接口来实现每个电流源的独立接通/关断、亮度电平、闪烁和灰度等级控制
• 内部电流基准
• 提供了两个 I²C 地址 (LTC3207 00110110，LTC3207-1 00110100)
• 用于异步 LED 接通/关断控制的可配置ENU引脚
• 自动或强制模式切换
• 内部软起动功能可限制浪涌电流
• 短路/热保护
• 4mm x 4mm 24 引脚 QFN 塑料封装

• description

  The LTC®3207/LTC3207-1 is a highly integrated multi-display LED driver. The device includes a high-efficiency, low-noise charge pump to power 12 general-purpose LED current sources and one camera LED current source. The LTC3207/LTC3207-1 requires only 5 small ceramic capacitors to form a complete LED power supply and current controller. In addition, two I2C addresses are provided. The display current is set by an internal accurate current reference. Independent dimming, on/off, flickering, and grayscale control of all common current sources is achieved via an I2C serial interface. A 6-position linear DAC can be used to adjust the brightness level of each common LED current source. The CAM current source features a 4-position linear DAC for brightness regulation. The LTC3207/LTC3207-1 charging pump optimizes efficiency based on the voltage across the LED current source. The device is powered on in 1x mode and will automatically switch to boost mode when either enabled LED current source begins to enter a voltage drop state. The first voltage drop will convert the IC to 1.5x mode, and the subsequent voltage drop will switch LTC3207/LTC3207-1 to 2x mode. When a data register is updated through the I2C port, the device is reset to 1x mode.

• apply

  • 采用QVGA⁺ 显示屏的可视电话