ESP32-WROOM-32
Midi LED Matrix Sequencer
Overview
A compact studio desktop MIDI-controlled 16x16 LED matrix sequencer powered by dual 18650 batteries with USB programming and TRS MIDI/SYNC interfaces.
GadySystem architecture
POWER
MCU
- POWER → MCUPowerPower supply
Bill of materials
| Part number | Type | Component | Manufacturer | Package | Qty | Datasheet | Match |
|---|---|---|---|---|---|---|---|
| UJ20-C-H-G-MSMT-P16-TR | POWER | USB-C Power Jack Power input | Same Sky | - | 1 | Matched | |
2 alternatives consideredAI verified | |||||||
| ESP32-WROOM-32 | MCU | ESP32-WROOM-32 Main controller | Espressif Systems | Reel | 1 | Matched | |
2 alternatives consideredAI verified | |||||||
Build guide
4-6 hoursIntermediate
1
Procurement & Preparation
- Source and verify all required components including UJ20-C-H-G-MSMT-P16-TR USB-C Power Jacks and ESP32-WROOM-32 modules according to the Bill of Materials.
- Inspect the dual 18650 battery holder, 16x16 LED matrix panels, TRS MIDI jacks, and custom PCB for defects or trace damage.
2
Hardware Assembly & Wiring
- Solder the UJ20-C-H-G-MSMT-P16-TR USB-C Power Jack onto the designated pads of the PCB using lead-free solder.
- Mount and solder the ESP32-WROOM-32 module onto the main PCB, ensuring proper pin alignment with power and data traces.
- Wire the 5V and GND power rails from the USB-C power input and dual 18650 battery management circuit to the ESP32-WROOM-32.
- Integrate the 16x16 LED matrix display and TRS MIDI/SYNC jacks, soldering data lines and audio connectors to the main controller board.
3
Firmware Setup
- Connect the Midi LED Matrix Sequencer to a host computer via the USB-C port using a data-capable USB cable.
- Configure the development environment (PlatformIO or Arduino IDE) with the required FastLED and MIDI libraries for the ESP32.
- Compile and flash the sequencer firmware binary onto the ESP32-WROOM-32 module.
4
Testing & Calibration
- Perform a power-on self-test (POST) by switching to battery power and verifying the 16x16 LED matrix initializes with a startup animation.
- Test MIDI input and output functionality by sending and receiving note data through the TRS MIDI jacks using an external MIDI controller.
- Calibrate LED matrix brightness levels and test charging circuit operation with dual 18650 cells installed.
Document
Midi LED Matrix Sequencer
A compact studio desktop MIDI-controlled 16x16 LED matrix sequencer powered by dual 18650 batteries with USB programming and TRS MIDI/SYNC interfaces.
Design Overview
| Item | Details |
|---|---|
| Product Type | Midi LED Matrix Sequencer |
| Key Functions | 16x16 WS2812B LED matrix driving over SPI, MIDI input via 3.5mm TRS jack, SYNC input for musical synchronization via 3.5mm TRS jack, Rechargeable dual 18650 Li-Ion battery power with power switch, USB interface for microcontroller programming and serial communication |
| Power Source | Dual 18650 Li-Ion Battery with USB Charging |
| Connectivity | USB, MIDI TRS, SYNC TRS |
| Size | Compact desktop enclosure |
| Environment | Studio desktop |
| Difficulty | Intermediate |
| Est. Time | 4-6 hours |
System Architecture
Power Topology: USB-C 5V → MCU 3.3V LDO
Module List
| Module ID | Type | Name | Function | Voltage |
|---|---|---|---|---|
| POWER | POWER | USB-C Power Jack | Power input | 5V |
| MCU | MCU | ESP32-WROOM-32 | Main controller | 3.3V |
Design Schemes
Midi LED Matrix Sequencer ★
Key IC selection
main MCU and matrix controller
- Need: Dual-core processing, Wi-Fi/BT optional, sufficient RAM for framebuffer, hardware UART for MIDI, and high-speed DMA for WS2812B timing.
- Class: 32-bit Wi-Fi/BLE MCU with rich peripherals
- Shortlist: ESP32-WROOM-32, ESP32-S3-WROOM-1
- Pick: Select ESP32-WROOM-32 module with integrated flash based on cost and robust peripheral availability.
Battery Management and Power Path
- Need: Safe charging for dual 18650 cells in parallel, USB-C power input handling, and high-current 5V boost converter for 256 WS2812B LEDs at peak brightness.
- Class: 1-cell Li-Ion Battery Charger + Synchronous Boost DC-DC Regulator
- Shortlist: BQ25606 + TPS61088, MP2639A dual-cell charger/boost IC
- Pick: Select monolithic dual-cell synchronous switch-mode charger and boost converter to minimize PCB footprint and handle high LED transient currents.
Risk register
| ID | Area | Severity | Detail | Mitigation |
|---|---|---|---|---|
| r1 | power | high | 256 WS2812B LEDs at full white draw upwards of 15A peak, which will cause severe voltage drop on a dual 18650 battery setup and trigger over-current protection or cause MCU resets. | Implement strict firmware brightness limiting, add bulk capacitance (low-ESR electrolytic + ceramic array) near the LED power distribution, and run thick copper power planes. |
| r2 | thermal | med | High sustained LED density in a compact enclosure will trap heat, potentially degrading battery life and causing thermal stress on linear regulators or power switches. | Incorporate thermal vias under the power ICs, ensure proper ventilation paths in the enclosure design, and add a dynamic thermal throttling routine in firmware. |
| r3 | emi | med | High-frequency PWM signals driving 256 WS2812B data lines act as antenna arrays, potentially corrupting sensitive optoisolated MIDI input streams. | Route MIDI optoisolator circuitry away from the LED data lines, use shielded 3.5mm jacks, and add series damping resistors (33-100 ohm) on ESP32 LED data output pins. |
Key Components
2/2 modules matched to real parts. See the BOM tab for the full component table.
USB-C Power Jack (UJ20-C-H-G-MSMT-P16-TR)
None of the candidates match the primary MPN UJ20-C-H-G-MSMT-4B-P16-TR closely enough, as they all have different featur
ESP32-WROOM-32 (ESP32-WROOM-32)
Candidate 2 exactly matches the primary MPN 'ESP32-WROOM-32' and is manufactured by Espressif Systems.
Build Summary
- Difficulty: Intermediate
- Estimated time: 4-6 hours
- Tools required: Soldering Iron, Lead-free Solder, Flux, Digital Multimeter, Wire Strippers, Flush Cutters
See the Build tab for the full step-by-step assembly guide.
Generated by YuanQi AI Design System · Query: 16x16 LED Matrix Driver with appropriate microcontroller. Matrix is over SPI. Must have MIDI and SYNC IN for musical purposes. Power switch, rechargeable using 18650 cells. USB Interface to program and talk to microcontroller.