Devlog 2: ESP32 Handheld Calculator Power Subsystem

Author: Ibrahim Qureshi

Overview

This log details the three-stage power delivery system designed for the custom terminal device. Generating a stable, noise-free supply is critical to prevent brownouts during wireless transmission and to prevent artifacts on the ILI9341 display.

System Architecture

[ 18650 Battery ] 
       |
[ TP4056 Charger ] -> (Protection & USB Charging)
       |
[ MT3608 Boost ]   -> (Steps up to 5V)
       |
[ AMS1117 LDO ]    -> (Drops to clean 3.3V)
       |
[ ESP32 ]