Open source headphone design based on RP2040 and PCM3060

All files are open source, including software, hardware and 3D printing shells, and how to make and assemble them are described in detail, especially the EQ equalization filter test and frequency response test are explained in detail. The main control uses RP2040 + TI 24-bit asynchronous stereo audio codec PCM3060 with 96/192kHz sampling rate.

Schematic PCB

QN9090DK: Development platform for QN9090/30(T) wireless MCU

Highly Scalable QN Wireless MCU Application Development Platform This development kit is enabled by the QN9090T which supports Bluetooth 5 and NFC.

Schematic PCB

255 W, 80PLUS® Silver Certified ATX Power Supply GreenPoint® Reference Design

OPen Book: a fully open source e-book that supports all languages ​​and breaks down working principles (schematics, PCB, source code, etc.)

Open Book is an open hardware device for reading books in all languages ​​of the world. It includes a large screen and navigation buttons, as well as audio options for accessibility and ports to expand its functionality. Its fine screen printing aims to demystify Open Book's own design, breaking down for curious readers how the book works and how they can create one for themselves.

Schematic PCB

OM13536: SA639DH Demonstration Board

Plant Bot: an open source project for caring for potted plants based on ESP32

Plant Bot is an open source project based on ESP32 that allows a single PCB to perform the functions of detecting humidity, watering, providing lighting, and controlling and communicating with the user via WiFi/BLE.

Schematic PCB

Wireless charger

This is a reference design for a wireless charger. The working principle is: power transmission between objects through electromagnetic induction. A fully analog RL78/G11 microcontroller, ISL28006 current sense amplifier and HIP2106A MOSFET driver are used.

MCU-based Alexa voice service solution

The i.MX RT AVS solution based on Alexa Built-in MCU is a turnkey hardware and single-source software solution for adding voice control with Alexa.

Schematic PCB

NxH3670 SDK board

This user manual describes the different user configurations of the NxH3670 SDK board.

Tracer: ESP32-based wearable sports tracker

Have you ever thought about attaching an inertial measurement unit (IMU) to an object to track its posture and motion? Tracer provides high-performance, safe, reliable and low-cost object tracking. Tracer can be easily attached to objects using Velcro. It can tilt and track rhythm as the bike's frame tilts, it can record the number of shots taken with a tennis racquet, and it can even differentiate between topspin and chip shots. Let your imagination run wild and explore more interesting applications of Tracer!

Schematic PCB

snapVCC: 3.3/5 V ultra-efficient voltage regulator that mounts directly on your 9 V battery (schematic, PCB, etc. included)

snapVCC is a highly portable and convenient power supply for your electronics projects. It's designed to fit a 9V battery and provide you with 3.3V or 5V power wherever you need it. What can you do with snapVCC? Many circuits require a regulated 3.3 or 5 volt power supply. 9V batteries are an easily available power option. A common method of using a 9V battery to power a circuit is to use a linear regulator IC circuit to step down the voltage.

Schematic PCB

CN0281

Using ADuC7060/ADuC7061 precision analog microcontroller to build a thermocouple temperature sensor with cold junction compensation based on automotive SENT interface

Schematic PCB

Tah: Arduino-compatible BLE platform, which can be used as beacons, microcontrollers and HID devices (including schematics, source code, etc.)

Tah - Control anything from your smartphone, open source, Arduino-compatible Bluetooth Low Energy (BLE) platform that can be used as a beacon, microcontroller, and HID device.

Schematic PCB

CN0234

Single-supply, micropower toxic gas detector using electrochemical sensors

Schematic PCB

60 W USB-PD and Quick Charge 3.0 Buck-Boost Reference Design Documentation Package

battery powered fluorescent lamp

Battery-operated fluorescent lighting projects often appeared in hobby electronic magazines in the 1980s. I always thought that fluorescent lamps were devices that only used AC power at that time. Those articles about using batteries to light miniature fluorescent lamps attracted me. I made some fluorescent lights, but I couldn't get good practical use out of them from a lamp efficiency and longevity perspective. That's because I was just reading the article and knew nothing about the theory of discharge lamps or even electronics. I don't know what to change to get good results, and I'm losing interest in it. However I found a battery powered fluorescent light project online that was identical to the schematic I was working on. So I "revived" the project after 30 years with modern driver circuits and correct theory.

Schematic PCB

pmod-gnss：GNSS PMOD、GPS + Glonass

This design is a PMOD with the ublox NEO GNSS receiver footprint. Able to receive GPS and GLONASS simultaneously.

Schematic PCB

BPW34 photodiode acts as a solar cell to make a supercapacitor watch (schematic diagram, etc.)

The standby time is acceptable and in good condition, more than 7 days.

Schematic PCB

PNEV512R: EXPLORE-NFC - Exclusively supplied by element14

EXPLORE-NFC - exclusively supplied by element14

CN0280

Integrated isolated power supply, powerful fully isolated current sensing circuit for solar photovoltaic converters

Schematic PCB