The Chimer 03

C
PCB
Hardware
Junior Design
Audio
ESP32
Spring 2026
Timer
Recording

This is a musical detection timer. It functions as both a timer and a small electronic musical instrument that can record and play a short melody. It uses the ESP32, VL53L0X time of flight sensor, TM1637 display, CDS-4528-44XX speaker, LM386 audio amplifier, and Adafruit LED arcade buttons. The ESP32, time of flight sensor, display, and arcade buttons all communicate over I2C, while the audio amplifier receives a sine wave from the ESP32. This project also features a custom audio amplifier PCB that cleans and attenuates the sine wave from the ESP32 for louder and cleaner sound quality. Notable achievements from this project include music recording, case design and printing, and sound state logic. While computationally simple, the music recording is robust and accurate. The design of the case was a fun way to “break” the “no bread boards at verification rule”, as we modeled our case off of a bread board. Our state logic is very simple yet prevents state errors by routing all other states through standby mode.

9 Lifts 

Artifacts

Name Description
System Design Document This is the design document of the chimer. It contains documentation of all the blocks, as well as our verification process.   Download
Project Sumary Video Short video discussing the challenges our team faced as well as successes and future goals.   Link
LM386 Audio Amplifier PCB This is an audio amplifier based on the design within the LM386 datasheet. It has a voltage gain of 20 V/V, signal attenuation, and signal filtering.   Download
Project Timeline This is the project timeline with major dates.   Download
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