Fix for LCD Replacement Mod Blinking

You may have noticed that after you upgraded the LCD in your system to a new one, it starts to blink after a short time (it generally happens when using rechargeable batteries). The issue is that some replacement LCDs have a higher minimum voltage threshold than others. When ordering a replacement screen, it can be hard to figure out what the minimum voltage is. If you bought an LCD with a lower minimum voltage than the system you are using, the screen will blink as the battery voltage drops.

There are two ways to fix this problem. Method 2 is preferred and greatly increases battery life but method 1 is the easiest.

Method 1

This method uses an external DC to DC converter. You may be asking yourself, “Why would I want to convert DC to DC?” The answer is this: Because you can convert a lower voltage to a higher voltage. When using a DC to DC step up converter, as the battery voltage drops, your output voltage would remain the same. That means no more blinking LCDs! Battery life will be decreased when using a DC to DC converter to increase the voltage. Anyway, let’s get to it!

If you have not purchased your LCD yet, consider purchasing the LCD/Converter combo from our store (US residents only).

Here is a list of what you need along with affiliate links to purchase them:

• Digital Multimeter
• DC to DC Step-up Converter

Although I am using a Sega Nomad in my pictures, this applies to any system where the LCD can be replaced (assuming there is enough space for the converter).

Step 1:

Connect the inputs of the converter to your system (where your LCD normally gets power).

Step 2:

Turn on the system and measure the output voltage. Adjust the potentiometer until you get a reading of about 10.5 Volts.

Step 3:

Turn off the system and connect the outputs of the converter to the LCD you want to use. Also, make sure the composite input of the LCD is connected to the system.

Step 4:

Turn on the system with a game in it. If you see a picture, decrease the voltage with the potentiometer until the screen starts blinking. If the screen is off, make sure you have everything connected properly. If so, continue to step 5.

Step 5:

Now, increase the voltage with the potentiometer until the screen is on and not blinking, then turn it a tad more. This is where we are going to leave it.

Step 6:

If you were using an AC adapter, this is a good time to test it with the batteries. The ideal test would be letting it run until the batteries die. This way you can see that the LCD does not blink at all.

Step 7:

If the LCD did not blink, mount the converter in the system (I used hot glue to mount it). If you are concerned that the potentiometer might be moved when putting your system back together, you can use some hot glue on it to keep it in place. If the LCD did blink, increase the voltage output to the rated voltage of the LCD.

Method 2

In method 1 you add a DC-DC step up converter to increase the voltage for the LCD driver board. In method 2 you don’t use a DC-DC converter at all. Most of the LCDs you can buy are meant to be used with vehicle backup cameras. The LCD driver boards are designed to accept 12 VDC from a vehicle. The LCD driver board takes the 12 VDC and steps it down to around 5 VDC. In method 2 you use a 5 VDC source and bypass the DC-DC converter on the LCD driver board. If you are using the recommended LCD/driver board, solder a wire to jumper these points:

If you have a different LCD driver board you will have to figure out where the DC-DC step down converter is. If you aren’t up to it then I’d stick with method 1.

Once you do this DO NOT connect this to anything greater than 5 Volts! If you are doing the Sega Nomad Mod you need to use this voltage point instead of the one near the power connector to power the LCD:

You can reuse the connector from the old LCD when using this method which makes it a bit cleaner.

That is it! You now have a system with an upgraded LCD that doesn’t blink. Let me know if you have any questions.