RTD2660-TV_液晶电视驱动板应用电路原理图纸见百度云盘。
RTD2660-TV_LCD TV driver board application circuit schematic drawings see Baidu Yunpan.
以rtd2660液晶驱动板为例说明(自己的电视)
Take rtd2660 LCD driver board as an example to illustrate (own TV)
现象:电源板输出电压正常，但是按开关没反应:
Phenomenon: The output voltage of the power supply board is normal, but the switch does not respond:
从先易后难的顺序着手检查
Start with the sequence of easy and difficult.
1、目测板子有无元件异常，通电用手触摸板子各处，看有无温度异常，有时处理芯片坏了温度很高，一摸就发现了
1. Whether there are abnormal components in the visual inspection board, touch the board everywhere with the power-on hand to see if there is abnormal temperature. Sometimes the processing chip breaks down and the temperature is very high.
2、然后我习惯先检查驱动板上的各个供电。
2. Then I used to check the power supply on the drive board first.
由于电源板输出通常只有12v和5v，所以驱动板上都有几个DC/DC稳压器来转换驱动板所需的电压。
Since the output of the power board is usually only 12V and 5v, there are several DC/DC regulators on the drive board to convert the required voltage of the drive board.
(少量机型的电源板也会输出3.3v,2.5v等电压给驱动板)
(A small number of power boards will also output 3.3v, 2.5V equal voltage to the drive board)
稳压器的样子看图一目了然
The shape of the regulator is clear at a glance.
一般有5v,3.3v,2.5v,1.8v等，测量一下几个稳压芯片的输入和输出电压，此机如果是供电问题引起的故障那么很快就找到故障点了。
Generally, there are 5v, 3.3v, 2.5v, 1.8v, etc. to measure the input and output voltage of several regulator chips. If this machine is caused by power supply problems, it will find the fault point quickly.
3、如果各稳压器电压都正常，那么继续查，还是先简单的来，
3. If the voltage of each regulator is normal, then continue to check, or simply come first.
供电都正常，那么按键板上的各个按键应该已经有电压了，然后用万用表测量，当按开关件时，按键上的电压有没有被拉低0v，如果没有，那么开关键坏了,换个按键就能修复故障了。
Power supply is normal, then the buttons on the keyboard should have voltage, and then use a multimeter to measure whether the voltage on the keyboard has been pulled down by 0 V when pressing the switch. If not, the switch key is broken and a change of key can repair the fault.
4、如果有开关电压跳变，那么开关按键也排除了，继续检查，供电有了，那么再查芯片工作所需要的时钟。(不同的处理芯片所需要的晶振频率是不同的)
4. If there is switching voltage jump, then the switch button is excluded. Continue to check. If the power supply is available, then check the clock needed for the chip to work again. (Different processing chips require different crystal frequencies)
用万用表测晶振两端电压有无压差，当然这样只能大概判断下，有示波器看波形当然最好。
Measuring the voltage difference between the two ends of crystal oscillator with multimeter, of course, this can only be judged roughly. It is of course the best to have oscilloscope to see the waveform.
5、mcu芯片工作所需的时钟也有了，再检查芯片工作所需条件复位，因为芯片pdf不好找，而且即使找到了，不同厂商定义的引脚可能也不同，费时间。
5. The clock needed for the MCU chip to work is also available. It takes time to check the condition reset for the chip to work again, because the PDF of the chip is not easy to find, and even if it is found, the pins defined by different manufacturers may be different.
|
