LED电子显示屏维修手册

LED电子显示屏维修手册 判断问 题 快递公司问题件快递公司问题件货款处理关于圆的周长面积重点题型关于解方程组的题及答案关于南海问题 必须先主后次方式的处理，将明显的、严重的先处理，小问题后处理。短路应为最高优先级。 1、 电阻检测法，将万用表调到电阻档，检测一块正常的电路板的某点的到地电阻值，再检测另一块相同的电路板的同一个点测试与正常的电阻值是否有不同，若不同则就确定了问题的范围。 2、 电压检测法，将万用表调到电压档，检测怀疑有问题的电路的某个点的到地电压，比较是否与正常值相似，否则确定了问题的范围。 3、 短路检测法，将万用表调到短路检测挡(有的是二极管压降档或是电阻档，一般具有报警功能)，检测是否有短路的现象出现，发现短路后应优先解决，使之不烧坏其它器件。该法必须在电路断电的情况下操作，避免损坏表。 4、 压降检测法，将万用表调到二极管压降检测档，因为所有的IC都是由基本的众多单元件组成，只是小型化了，所以在当它的某引脚上有电流通过时，就会在引脚上存在电压降。一般electricity at no cost, revenue from electricity sales. Poverty alleviation to the removal, to desperate farmers out of poverty, in conjunction with urbanization, new communities are centrally placed. Poverty in the enterprise, enterprise more powerful, more social responsibility, they should allow more people to enjoy the fruits of development. Conditions to encourage private enterprises to establish Charity Fund for poverty alleviation, employment, grants, financial aid and other forms of poverty alleviation activities, let poverty alleviation aid corporate social responsibility in the specific embodiment, the proper meaning of giving back to the community. Finally reveals to implement poverty alleviation policies, older age, incapacity, cannot be achieved through industry support and employment support, such as poverty, children and unable to support the poor, Lo-Fi policy reveals the role to play, eventually incorporated into the low range, and fundamentally solve the problem of poverty. (C) establishing and perfecting retreat mechanism. Poverty alleviation is a dynamic project, we must strengthen the farmers ' information management, dynamic management of poor, really "poor" no place to hide, "poverty" a timely exit, "poor" and "return to the poor" get maximum support and help. To build up the information network system of the poor, poverty the basic information and dynamic entry to the system, to implement dynamic management. According to pro-poor development, timely adjustment on 同一型号的IC相同引脚上的压降相似，根据引脚上的压降值比较好坏，必须电路断电的情况下操作。该 方法 快递客服问题件处理详细方法山木方法pdf计算方法pdf华与华方法下载八字理论方法下载 有一定的局限性，比如被检测器件是高阻的，就检测不到了。 LED电子显示屏维修手册，单元板常见问题的处理步骤，单元板故障: A.整板不亮 1、 检查供电电源与信号线是否连接。 2、 检查测试卡是否以识别接口，测试卡红灯闪动则没有识别，检查灯板是否与测试卡同电源地，或灯板接口有信号与地短路导致无法识别接口。(智能测试卡) 3、 检测74HC245有无虚焊短路，245上对应的使能(EN)信号输入输出脚是否虚焊或短路到其它线路。注:主要检查电源与使能(EN)信号。 B.在点斜扫描时，规律性的隔行不亮显示画面重叠 1、 检查A、B、C、D信号输入口到245之间是否有断线或虚焊、短路。 2、 检测245对应的A、B、C、D输出端与138之间是否断路或虚焊、短路。 electricity at no cost, revenue from electricity sales. Poverty alleviation to the removal, to desperate farmers out of poverty, in conjunction with urbanization, new communities are centrally placed. Poverty in the enterprise, enterprise more powerful, more social responsibility, they should allow more people to enjoy the fruits of development. Conditions to encourage private enterprises to establish Charity Fund for poverty alleviation, employment, grants, financial aid and other forms of poverty alleviation activities, let poverty alleviation aid corporate social responsibility in the specific embodiment, the proper meaning of giving back to the community. Finally reveals to implement poverty alleviation policies, older age, incapacity, cannot be achieved through industry support and employment support, such as poverty, children and unable to support the poor, Lo-Fi policy reveals the role to play, eventually incorporated into the low range, and fundamentally solve the problem of poverty. (C) establishing and perfecting retreat mechanism. Poverty alleviation is a dynamic project, we must strengthen the farmers ' information management, dynamic management of poor, really "poor" no place to hide, "poverty" a timely exit, "poor" and "return to the poor" get maximum support and help. To build up the information network system of the poor, poverty the basic information and dynamic entry to the system, to implement dynamic management. According to pro-poor development, timely adjustment on 3、 检测A、B、C、D各信号之间是否短路或某信号与地短路。注:主要检测ABCD行信号。 C.全亮时有一行或几行不亮 1、检测138到4953之间的线路是否断路或虚焊、短路。 D.在行扫描时，两行或几行(一般是2的倍数，有规律性的)同时点亮 1、 检测A、B、C、D各信号之间是否短路。 2、检测4953输出端是否与其它输出端短路。 E.全亮时有单点或多点(无规律的)不亮 1、 找到该模块对应的控制脚测量是否与本行短路。 2、 更换模块或单灯。 F.全亮时有一列或几列不亮 1、 在模块上找到控制该列的引脚，测是否与驱动IC(74HC595/TB62726)输出端连接。 G.有单点或单列高亮，或整行高亮，并且不受控 1、 检查该列是否与电源地短路。 electricity at no cost, revenue from electricity sales. Poverty alleviation to the removal, to desperate farmers out of poverty, in conjunction with urbanization, new communities are centrally placed. Poverty in the enterprise, enterprise more powerful, more social responsibility, they should allow more people to enjoy the fruits of development. Conditions to encourage private enterprises to establish Charity Fund for poverty alleviation, employment, grants, financial aid and other forms of poverty alleviation activities, let poverty alleviation aid corporate social responsibility in the specific embodiment, the proper meaning of giving back to the community. Finally reveals to implement poverty alleviation policies, older age, incapacity, cannot be achieved through industry support and employment support, such as poverty, children and unable to support the poor, Lo-Fi policy reveals the role to play, eventually incorporated into the low range, and fundamentally solve the problem of poverty. (C) establishing and perfecting retreat mechanism. Poverty alleviation is a dynamic project, we must strengthen the farmers ' information management, dynamic management of poor, really "poor" no place to hide, "poverty" a timely exit, "poor" and "return to the poor" get maximum support and help. To build up the information network system of the poor, poverty the basic information and dynamic entry to the system, to implement dynamic management. According to pro-poor development, timely adjustment on 2、 检测该行是否与电源正极短路。 3、 更换其驱动IC。 H.输出有问题 1、 检测输出接口到信号输出IC的线路是否连接或短路。 2、检测输出口的时钟锁存信号是否正常。 3、 检测最后一个驱动IC之间的级连输出数据口是否与输出接口的数据口连接或是否短路。 4、 输出的信号是否有相互短路的或有短路到地的。 5、 检查输出的排线是否良好。 J.显示混乱，但输出到下一块板的信号正常 1、 检测245对应STB锁存输出端与驱动IC的锁存端是否连接或信号被短路到其它线路。 K显示混乱，输出不正常 1、 检测时钟CLK锁存STB信号是否短路。 2、 检测245的时钟CLK是否有输入输出。 3、 检测时钟信号是否短路到其它线路。 electricity at no cost, revenue from electricity sales. Poverty alleviation to the removal, to desperate farmers out of poverty, in conjunction with urbanization, new communities are centrally placed. Poverty in the enterprise, enterprise more powerful, more social responsibility, they should allow more people to enjoy the fruits of development. Conditions to encourage private enterprises to establish Charity Fund for poverty alleviation, employment, grants, financial aid and other forms of poverty alleviation activities, let poverty alleviation aid corporate social responsibility in the specific embodiment, the proper meaning of giving back to the community. Finally reveals to implement poverty alleviation policies, older age, incapacity, cannot be achieved through industry support and employment support, such as poverty, children and unable to support the poor, Lo-Fi policy reveals the role to play, eventually incorporated into the low range, and fundamentally solve the problem of poverty. (C) establishing and perfecting retreat mechanism. Poverty alleviation is a dynamic project, we must strengthen the farmers ' information management, dynamic management of poor, really "poor" no place to hide, "poverty" a timely exit, "poor" and "return to the poor" get maximum support and help. To build up the information network system of the poor, poverty the basic information and dynamic entry to the system, to implement dynamic management. According to pro-poor development, timely adjustment on 注:主要检测时钟与锁存信号。 L.显示缺色 1、 检测245的该颜色的数据端是否有输入输出。 2、 检测该颜色的数据信号是否短路到其它线路。 3、 检测该颜色的驱动IC之间的级连数据口是否有断路或短路、虚焊。注:可用电压检测法较容易找到问题，检测数据口的电压与正常的是否不同，确定故障区域。 electricity at no cost, revenue from electricity sales. Poverty alleviation to the removal, to desperate farmers out of poverty, in conjunction with urbanization, new communities are centrally placed. Poverty in the enterprise, enterprise more powerful, more social responsibility, they should allow more people to enjoy the fruits of development. Conditions to encourage private enterprises to establish Charity Fund for poverty alleviation, employment, grants, financial aid and other forms of poverty alleviation activities, let poverty alleviation aid corporate social responsibility in the specific embodiment, the proper meaning of giving back to the community. Finally reveals to implement poverty alleviation policies, older age, incapacity, cannot be achieved through industry support and employment support, such as poverty, children and unable to support the poor, Lo-Fi policy reveals the role to play, eventually incorporated into the low range, and fundamentally solve the problem of poverty. (C) establishing and perfecting retreat mechanism. Poverty alleviation is a dynamic project, we must strengthen the farmers ' information management, dynamic management of poor, really "poor" no place to hide, "poverty" a timely exit, "poor" and "return to the poor" get maximum support and help. To build up the information network system of the poor, poverty the basic information and dynamic entry to the system, to implement dynamic management. According to pro-poor development, timely adjustment on