DIY Power Outlet Fix and LED Backlight Modification

If you're interested in DIY power outlets, you might want to check out this article.

When encountering a power socket issue caused by a faulty SC662K-3.3V three-terminal regulator (U4), the original chip is in an SOT-23 package. If you don't have a small 3.3V chip, you can remove the second pin of the SOT-89 package MD7133H and directly solder it in place to successfully fix the issue.

Here's a teardown image for reference:

To modify the backlight, first find an LED strip, connect it in series, and place it across the original 8.2V voltage regulator (D1) on the screen side. This will keep the backlight always on.

After testing, from the power supply to the purely resistive load, the power, current, and voltage accuracy are all up to standard. The measured power is 1.5% higher than what is shown on a home electric meter, with a minimum measurement of 0.5W. However, home electric meters can only measure loads above 5W, and below that, they show zero.

Here is an example of a 2.3W desk lamp, which cannot be displayed on the electric meter.

Below is the desk lamp at its maximum brightness, measuring 5.5W.

Completed.