Prema 公司的PR4010是10路LED恒流驱动器，可以用于单列LED和点阵LED显示器驱动.

      PR4010工作电压为5V，串行接口，由外部来控制LED的亮度，可用于LED状态显示器， 条形图显示器，符号指示器，仪表显示器和LED点阵文本显示器.本文介绍了PR4010的主要特性， 方框图， 典型应用电路以及在点阵显示器中应用电路.

      10-Channel LED Driver PR4010
      The PR4010 is a 10 channel constant current driver with serial interface for LED displayapplications. The LED current is programmable via an external resistor.
It can be used for single lines of LED， as well as for matrix displays.
The device is available in a 20-pin SSOP package.

      PR4010主要特性:
      10 constant current sink channels
      Supply voltage 5V
      Serial interface， shift register with latch
      External brightness control
      Current output with max. sink current of 10mA

      应用:
      LED status displays
      Bargraph displays
      Indicator signs
      Instrument displays
      LED matrix text displays

图1.PR4010方框图

图2.PR4010典型应用电路

图3.PR4010在点阵显示器中应用电路

      In this example， five outputs are used to select one line via an external PNP transistor.

      Two PR4010 are cascaded to provide a total of 20 drivers. When multiplexing the control signals more than 75 LEDs in the display matrix can be operated.