Teardown pictures of the GB BOY from GangFeng (also randomly transliterated to GongFeng or KangFeng). This is the monochrome "pocket" version.
Power requirements are close to the original GameBoy Pocket.
My model was apparently made in January 2013.
The infamous self-oscillating DC-DC voltage converter board, providing 5V for logic, along with 9V and 20V for the LCD. The coil is on the back.
Close up of the interesting parts. In traditional Chinese style, the main ASIC is custom KF branded and runs on 5MHz (not sur if it's PLL adjusted to the original GB frequency or just needed to compensate for video logic quirks). Two 6264 8kB SRAM chips probably making up WRAM and VRAM. A Princeton PT2308 headphone amp and a super common LM324 for the built-in speaker. Also a HC74 and a HC86 either for reset, link communication or LCD signals. Go figure.