CCD相机系统中驱动电路的设计

Design of Drive Circuit for CCD Camera System

目前,线阵CCD图像传感器的种类很多,驱动时序的产生方法也是多种多样。CCD时序驱动电路的设计是CCD应用的关键,只有设计出符合要求的驱动时序,CCD器件才能稳定可靠的工作。常用的驱动方法存在某些缺点。在详细了解线阵CCD器件μPD795,分析其驱动时序与电路逻辑后,没有使用常规方法,而是使用CPLD进行功能的实现。该方法采用CPLD产生驱动,按要求写好VHDL代码产生可执行文件,通过JTAG接口下载到可编程器件中。实验结果表明该电路稳定可靠,在线阵CCD驱动电路中具有一定的代表性。

At present,there are many different types in linear arr.ay CCD image sensor, and the timing - driven method is multiplex. The design of drive circuit is the key for application of CCD. Only to design right timing - pulse can CCD device work stably and reliably. There are some shortcomings in the routine driven approach. For linear CCD μPD795,after analysing the timing - pulse and Circuit logic, using the CPLD for the functional realization. This method does not use the routine approach but use CPLD to create pulse. VHDL code is written and then the operational file is produced,through the JTAG interface downloaded to programmable devices. The experimental results show that the circuit is stable and reliable. It is representative in linear array CCD circuit driver.