Power board packaging manufacturer: What is the LCD power board

Power board packaging manufacturer: after startup, filter the interference, rectification, PFC inductance and filter of the clutter in the mains power supply through the anti-interference circuit, and output 300 V DC voltage to the auxiliary power supply circuit. The auxiliary power supply starts to work, outputs 5v voltage, and sends it to the digital board CPU circuit through the output plug-in port 1 of the power board. The CPU circuit outputs a high-level start voltage after reading data. Through pin 2 of the power board plug-in port, to the power board voltage stabilizing on-off control circuit, work, output voltage to the PFC oscillation circuit, and output high-frequency square wave pulse to drive the PFC switch tube to work. The reverse pulse generated by PFC inductance is used to generate 400V PFC voltage through rectification and filtering. The power factor correction voltage is sent to the main power supply circuit and the power factor correction voltage detection circuit to detect that the power factor correction voltage reaches 400V. The power factor correction detection switch circuit outputs the voltage to the main power supply oscillation circuit, and the main power supply oscillation circuit outputs the high-frequency square wave pulse to the main power supply power switch circuit. The switch tube works to drive the switch transformer to work. The secondary induction outputs two sets of voltage, and after rectification and filtering, the output voltage is 12V and 24V. So far, the whole power board startup process is completed

Power panel packaging manufacturer: power panel principle - maintenance experience of LCD power panel

Power board packaging manufacturer: 1. When repairing the LCD power supply, first confirm the status of the safety tube and whether the safety tube is intact. Generally, the switch tube in the PFC correction circuit has no fault. Then measure whether there is a short circuit between the large electrolytic capacitor and the ground. The charging resistance is more than tens of kiloohms, indicating that there is no power failure. If the fuse is damaged, the first should check the switch tube of the PFC correction circuit, and the second should check the auxiliary power IC

Power board packaging manufacturer: 2. The power board can be removed from the TV for independent maintenance. During maintenance, it is only necessary to short circuit the triode C and E of the closing control circuit (or connect a resistance of about 1.5K at the 5V output end of the auxiliary power supply), and the whole machine is in the power-on state and outputs all voltages. In some switching power supply of LCD TV, the main switching power supply can work normally only when the 12V or 24V output terminal carries a certain power load. Therefore, at 24 V output, 36 V bulb dummy load of electric bicycle (or motorcycle bulb dummy load at 12 V output) can be connected

The editor mentioned above will tell you the working principle and maintenance experience of the LCD power panel. After reading these two aspects, you should have a simple understanding of the LCD power panel. Bian Xiao hopes that this knowledge can help you