0 Appreciate Project

Retro Gaming Handheld

I am a student in High School attempting to build a portable emulation machine. I walked into this with a tiny bit of knowledge of pcb work, and a couple years of cadding experience. This device is run off of the esp32 s3 wroom 1 module with 16mb of storage and a 8mb ram. I added an rgb screen, a mono sound system, and a charging system, along with a module for inserting sd cards. The goal was to make a complete emulation machine that is completely self sufficient with the only things coming from the computer being the code and games.

Power Systems

The power system was built off of a 3.7 lipo battery, but since the esp32 uses 3.3v, the voltage was too close to the working voltage of the esp32, so I used the BQ25895RTWR to act as the charging system along with the conversion to 5v. This module will convert the power to 5v so a buck converter can scale it back down to 3.3v. I lose a lot of power due to this conversion, but the power is sacrificed for more stability.

Display and Sound

This system uses a 40pin rgb screen that uses rgb666, but i downgraded to rgb444, mainly due to lack of pins on the esp32. This screen is 7 in and has a display resolution of 800x480. This system uses another buck converter that powers the backlight of the display, converting it from 5v to 9.9v. The sound is created by a 8ohm speaker, driven by the MAX98357AETE. This system could support 2 speakers, but due to power and spacing constraints, I decided on using only 1.

Computing and Interface

This system is powered off of an esp32 s3 wroom 1 n16r8. I added a 24pin i2c expansion to allow for more buttons and pins to interface with the esp32. The 24 pin i2c expansion drives the entire system of buttons for the user to interface with. This is powered by the TCA6424ARGJR.

Case

The case was cadded by me, using onshape. The case has support for a 7in lcd screen, a speaker, and buttons and the pcb. The case itself has a chamber containing the speaker, this is to isolate the sound and enhance it through the isolation and air behind the speaker. This case also has aeration through passive intake of air to reduce the temperatures of the parts.