开机电路检修流程图

 

                                     |

                                  CMOS/跳线

                                     |

                      --------------------------------

                     |                                |

                    正确                             不正确

                     |                                |

          测Power 开关的3.3V或5V                  跳回正确位

                     |

                ---------------------

               |                      |

             正常                    不正常

               |                      |

测南桥旁边的晶振是否起振,

起振电压为0.5V到1.6V左右        查紫线到Power 开关之间电路

               |

           ----------------------

           |                          |

        不正常                       正常

           |                          |

更换晶振旁边的滤波电容以      测Power开关到南桥或I/O之间是

及晶振本身                     否有低电平输入南桥或I/O

                                      |

                      ----------------------------

                      |                           |

                     有                           无

                      |                           |

查绿线到南桥或I/O 之间的             查Power 开关到南桥或I/O

电路是否损坏                         之间的元件,更换损坏元件

              |

           ---------------------

           |                       |

          完好                    损坏

           |                       |

更换南桥或者I/O(视开机电     更换元器件,修复电路

路而言)

 

注：开机电路常坏元器件器有接绿线的三极管、与开机电路有关的门电路芯片， 还有紫色线给Power 开关供电的三级管或是二级管等。

Power-南桥或I/O-绿线(开机过程)

|________|_______ |____________(低电平)