Gameboy Pocket Backlight Flicker

[batteries]

Hey Guys,

I bought a backlight from nonelectronics.com and it seems to work fine. However, following Bibin's tut at http://bibin.gg8.se/blog/projects-and-guides/how-to-backlight-a-game-boy-pocket/ , the screen flickers noticeably. And, the flicker seems to correspond with whats happening on the LCD. i.e. If I'm playing Zelda and I walk into a house, when it refreshes the whole screen to change to the inside of the house, the backlight dims, just for a second.

I know there is a way to stabilize the power supply to the backlight, but I don't know the details. Any experts out there care to help out?

Thanks!

 

[Ampersand]

This is due to the fact that both the CPU and the backlight will be drawing from the same power source (obviously, since they're both pulling from the batteries). When the CPU needs more power (i.e., to quickly buffer all the tiles for a new area, like when you walk in a house), it will draw more power, leaving your backlight with less power to draw.

The easiest way to get rid of this flicker is for a low-value resistor on the power line to your backlight. Do nonfinite backlights not come with a resistor? Each color takes different values, but 56 or 68 should be safe, removing the flicker without losing brightness.