“Hey everyone, what’s up?
So here’s something super interesting and cool: SANDWICH DOT IO.
It’s a Raspberry Pi system with onboard power, a dedicated cooling layer, and even RGB LEDs for aesthetics.
This setup was created to address a problem I encountered while working on a Raspberry Pi-based project:
I wanted to create a small game emulator using the RPI 3B+, but the problem was the power supply. A 5V adaptor was used for powering the Raspberry Pi.
A fan was also required to keep the Pi cool, but I had to add another 5V supply for it as we cannot plug it directly into the 5V of the Raspberry Pi.
So I made this simple system that consists of three layers, each made from FR4 PCB. The first layer, or battery layer, contains a power management IC (IP5306) with four Li-ion cells that give a stable 5V output for running the Pi and other stuff.
The second layer holds the Raspberry Pi in place by using the four mounting holes present on the Pi. I used PCB standoffs to hold the Pi in place.
It also has RGB LEDs (WS2812B) to make this setup look cool and hip; they are powered by the onboard Attiny85 MCU, and the color is controlled by a vertical push-button.
The third layer contains a cooling fan setup; a DC 5V fan is placed right on top of the Raspberry Pi processor and is powered by a proper fan driver made by using a Mosfet IC controlled by an Attiny13A; this concept was reused from one of my previous projects.
Because this setup has active cooling, the Raspberry Pi processor works great, and we could use this setup for power-hungry applications like running an emulation OS and playing DOOM, for example.
This Instructables is about the whole building process of this setup in-depth, so let’s get started.
Following were the materials used in this built-
Raspberry Pi Model 3B+ (can use any Pi version)
DC 5V Fan
AO4406 Mosfet IC
JST wire harness
Li-ion cell 18650 holder
Type C USB Port
Normal USB port
Slide switch ON OFF
indicator LEDs 0603 package