Wled 2 digi 1 analog

WLED LED Controller Board

A 4-channel WLED controller board built around the custom ESP32-S3 dev board. It supports two digital LED strips (e.g. WS2812B / SK6812 via level-shifted data lines) and one analog/PWM-dimmed strip (5-channel RGBWW), with individually fused power lines per strip output. Total sustained current capacity is ~10A, with 3–4A recommended per strip.

Overview

This board was designed to be a clean, self-contained controller unit. It plugs the ESP32-S3 board into a socket, handles all power routing, level shifting, MOSFET switching, and fusing in one place. Two power inputs are available, but only one should be active at a time — a Schottky diode (D2) and TVS diode (D1) protect the board when switching sources.

Motivation & Design Decisions

• Two power inputs, one at a time: A 5.5×2.1 mm barrel jack (J1) and a screw terminal input are both present for flexibility (bench supply vs. PSU). The Schottky diode D2 (SS34) on one path prevents backfeed between sources.
• TVS protection (D1, SMBJ26A): A 26V transient voltage suppressor clamps voltage spikes on the main 5V bus — important with longer LED strip wiring that can generate inductive kickback.
• Individually fused power lines: Each LED strip's 5V supply line runs through a dedicated ATO blade fuse holder (FH2/FH3/FH4). This isolates fault conditions to a single channel. ATO fuses are cheap, universally available, and hot-swappable.
• Level shifter (U1, 74AHCT125): The ESP32-S3 runs at 3.3V. WS2812B and similar LEDs expect 5V logic. The 74AHCT125 quad buffer shifts both DATA lines and clock signals to proper 5V levels reliably, without needing a dedicated 3.3V-compatible LED strip.
• N-channel MOSFETs for PWM dimming (Q1, Q6–Q9, IRLR7843TR): Five low-side N-channel MOSFETs handle the analog RGBWW channels. The IRLR7843TR has an extremely low RDS(on) (< 3 mΩ), so it barely heats up even at 3–4A per channel.
• P-channel MOSFETs for high-side switching (Q2, Q5): High-side switches on the digital strip power rails, driven by NPN transistors (Q3/Q4, MMBT4401). This allows the ESP32-S3 to cut power to strips entirely, useful for preventing LED ghost-lighting when WLED is in an "off" state.
• 5V buck for board logic (U2, AP63205WU): Derives a clean regulated 5V from the main bus specifically for the 74AHCT125 and the ESP32-S3 board's own regulator input. Uses a 4.7 µH / 1210 inductor (L1) on the switching output.
• Screw terminals in 2- and 3-pin configurations: Instead of using hard-to-find 1- or 5-pin terminals, standard KF301 2-pin, 3-pin and 4-pin blocks (5.0 mm pitch) are used throughout.

ESP32-S3 Pinout (Signal Mapping)

The controller board uses the following signals from the ESP32-S3 board headers:

Digital LED Strip Signals

Analog / PWM Strip Signals

Schematic

PCB Layout

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Bill of Materials

LCSC links point to the exact parts used. Where no LCSC link is listed, the part is a generic passive available from stock.

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Power Budget

Always size your ATO fuses to the strip's maximum draw, not the board's maximum. A 3A fuse per digital strip and a 5A fuse for the analog strip are good starting points.