Skip to content

Electronics Design and Production

Before designing and Producing PCB board I first calculated the approximate power consumption by components required for my final board.

Components Required:

  • Input Sensors: Ultrasonic sensor for detecting motion near the door and distance measurement. Xiao Camera to capture images.
  • Output Devices: DFMini PLayer + Speaker for Audio Prompts, , LED indicator for status.
  • MCU Features: XIAO ESP32-S3 MCU for processing, with built-in Wi-Fi for data transmission to the mobile app.

Power Requirements:

  • Voltage Requirements: Ultrasonic Sensor (HC-SR04): 5V, XIAO ESP32-S3 with Camera Module: 3.3V (regulated from 5V USB), DFMini Player: 3.2V to 5V, Speaker: Powered through DFMini Player
  • Combined Power Draw: Estimated total power draw around 500mA. Ultrasonic Sensor: 15 mA + XIAO ESP32-S3 with Camera Module: 300 mA + DFMini Player: Assuming average usage, let’s take 100 mA + 1k Resistors (4x): 20 mA + 3 Blue SMD LEDs: 60 mA.
  • Power Source: 5V, 2A USB power source

So after rough calculation, the power source of 5V, 2A (2000 mA) USB power source is well within the capacity of the estimated total power draw that is 500 mA.

First Iteration Final Board

  • For my initial final board iteration, I took inspiration from Jonne’s example and utilized KiCad for the PCB design. In this version, I integrated an ESP32 MCU along with an FTDI chip for programming and power management, alongside various breakout pins.
  • Here’s how it looks after milling and soldering.
  • Additionally, I created a separate bottom board specifically tailored for testing the ESP32 camera module.

Final Version Final Board

At some point, I thought about using the XIAO ESP32S3, which is pretty cool because it comes with a built-in camera, microphone, and SD card support. So, I made a board for it with inspiration from Quentorres.

Below you can see image of my final version final board with scematic: alt text alt text alt text - And to make sure everything was working, I tested it with a program that makes an LED blink on and off.

DFPlayer - A Mini MP3 Player:

The DFPlayer Mini MP3 Player is an affordable module that plays MP3 files and connects directly to a speaker. It can work alone with a battery and buttons or be integrated with microcontrollers like Arduino, ESP32, or Raspberry Pi using UART communication.

Pin Map:

image from google source

Specifications:

image from google source

The most simple way to use this module.

image from google source

For Testing DFPlayer, I went through this source:

For Testing of Blynk App to control LED ON-OFF, I followed this Youtube Tutorial: