led lcd tv power supply module connection.

Summary

In this video, the host demonstrates how to correctly install a power supply model in an LED TV. The video explains two installation methods, highlighting the common mistakes technicians make and the proper way to avoid damaging the TV. Viewers learn how to connect various components such as MOSFETs and feedback wires, discharge capacitors safely, and ensure stable power output. The host emphasizes safety precautions and provides insights on how to protect the power supply and improve TV functionality. The video is designed for technicians and electronics enthusiasts looking to improve their skills.

Takeaways

• 😀 Proper installation of a model in an LED TV's power supply is crucial to ensure its functionality.
• 💡 There are two common methods used by technicians for installing the model, with one being correct and the other incorrect.
• ⚠️ An incorrect installation may cause the TV to function briefly but ultimately lead to power supply voltage reduction and TV shutdown.
• 🔧 The correct installation involves careful handling of the model's MOSFET and feedback wires to maintain stable voltage output.
• ⚙️ Before installation, the main filter capacitor should be discharged to prevent potential damage to the circuit.
• 📏 The model's preset should be adjusted to limit the output voltage from the power supply to prevent damage to the TV's circuit or display.
• 🔌 The black and red wires of the model should be connected to the negative terminal of the capacitor and the positive terminal of the MOSFET drain, respectively.
• 🛠️ Proper connection of the blue and yellow wires to the secondary side of the power supply ensures correct feedback voltage and stability.
• 🔋 The model helps stabilize the power supply's output at 12V, ensuring safe operation of the TV’s backlight driver and other components.
• 📦 Once installed, the model can be secured inside the TV's body using double tape and housed in a protective box to prevent further damage.

Q & A

What is the main purpose of the video?

The main purpose of the video is to demonstrate how to correctly install a model into an LED TV power supply, highlighting both the wrong and right methods.

What is the common mistake technicians make when installing the model in an LED TV's power supply?

The common mistake technicians make is incorrectly connecting the feedback voltage, which leads to voltage drop and causes the TV to shut down after a short period.

Why is it important to discharge the filter capacitor before working on the power supply?

It is important to discharge the filter capacitor to avoid short circuits and prevent damage to the circuit, ensuring the model is safely installed.

What is the role of the MOSFET in the model, and how should it be handled?

The MOSFET helps regulate the power supply. If it gets too hot, a heat sink can be attached to it, but it can function well without a heat sink under normal conditions.

How does the feedback voltage affect the performance of the power supply and TV?

Incorrect feedback voltage causes the power supply to underperform, reducing the output voltage over time, which leads to the TV shutting down. Correct feedback ensures stable voltage and proper TV function.

What precautions should be taken when connecting the model to the TV’s power supply?

Precautions include discharging the filter capacitor, correctly wiring the model's red and black wires to the appropriate terminals, and ensuring proper feedback connection to avoid voltage fluctuations.

Why is it necessary to adjust the preset before supplying 220V input to the TV?

Adjusting the preset is necessary to reduce the initial output voltage from the power supply. If not adjusted, a higher-than-normal voltage could damage the TV’s circuit board or display.

What is the correct method to connect the blue and yellow wires of the model?

The blue wire should be connected to the ground terminal on the secondary side of the power supply, while the yellow wire should be connected to the positive 12V terminal.

What is the function of the feedback region in this model?

The feedback region in the model helps regulate the output voltage by ensuring the power supply provides a stable voltage to the TV, similar to how feedback regulators work in CRT TVs.

What steps should be followed after installing the model to ensure the TV works properly?

After installing the model, check the output voltage, ensure the connections are correct, and test the TV by turning it on. Once verified, the model should be placed inside its protective box to safeguard it from damage.