12V LED strips (RGB or RGBW) are one of the easiest ways to add smart lighting to a room – behind the TV, under cabinets, around the bed, or as indirect ceiling lighting.

With an ESP32, a few MOSFETs, and either ESPHome or WLED, you can:

• Control colour, brightness, and effects
• Integrate with Home Assistant (HA)
• Run everything locally, no cloud

This guide covers:

• Safe MOSFET wiring for 12V strips
• ESPHome light: configuration for RGB/RGBW
• A practical comparison to WLED (when to use which)

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1. Hardware Overview

For a classic 12V common-anode strip (RGB or RGBW):

• ESP32 DevKit
• 12V RGB or RGBW LED strip (common anode)
• 12V DC power supply (size: roughly strip watts ÷ 10 = amps)
• 3 or 4 × N-channel logic-level MOSFETs
  • e.g. IRLZ44N, IRLZ34N, AO3400, AOZ1284, etc. (logic-level important)
• 3 or 4 × gate resistors (100–220 Ω)
• Optional pull-down resistors (100 kΩ) from gate to GND for default OFF
• Wires, terminals, and enclosure

Important:
We’re controlling low-voltage 12V DC only here, not mains.

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2. 12 V RGB/RGBW Strip Basics

Most 12 V non-addressable strips are:

• Common anode (+12V shared)
• One separate channel per colour

RGB:

+12V  R  G  B

RGBW:

+12V  R  G  B  W

We will:

• Connect +12V directly to strip’s +12V
• Use MOSFETs on the low side (ground side) of each channel

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3. MOSFET Wiring (Low-Side Switching)

3.1 Basic Channel Wiring (One Colour)

For each channel (R, G, B, W):

12V PSU +  -----> LED strip +12V (common anode)

Strip R pin -----> Drain of MOSFET_R
MOSFET_R Source -> GND (shared with ESP32 and PSU)

ESP32 GPIOX --[220Ω]--> MOSFET_R Gate
MOSFET_R Gate --[100kΩ]--> GND (optional pull-down)

Repeat for G, B, and W with different GPIO pins and MOSFETs.

Shared ground is critical:
ESP32 GND, MOSFET sources, and PSU negative must be connected together.

3.2 Example GPIO Mapping

Let’s pick:

• Red → GPIO 25
• Green → GPIO 26
• Blue → GPIO 27
• White → GPIO 14 (for RGBW only)

You can adjust pins to avoid strapping or ADC pins as needed.

[Image idea: ESP32 → MOSFETs → 12V RGB strip wiring diagram]

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4. ESPHome RGB Controller

ESPHome can create a single light entity with RGB or RGBW channels that show up natively in Home Assistant.

4.1 Base ESPHome Config

esphome:
  name: esp32-rgb-strip
  platform: ESP32
  board: esp32dev

wifi:
  ssid: "YOUR_WIFI"
  password: "YOUR_PASSWORD"

logger:
api:
ota:

4.2 Define PWM Outputs (RGBW)

We’ll use LEDC PWM (hardware PWM on ESP32).

output:
  - platform: ledc
    pin: 25
    id: output_red

  - platform: ledc
    pin: 26
    id: output_green

  - platform: ledc
    pin: 27
    id: output_blue

  - platform: ledc
    pin: 14
    id: output_white

You can specify frequency: if needed (default is fine for strips).

4.3 RGBW Light Entity

light:
  - platform: rgbw
    name: "Living Room LED Strip"
    red: output_red
    green: output_green
    blue: output_blue
    white: output_white
    default_transition_length: 0.5s
    restore_mode: RESTORE_DEFAULT_OFF

For RGB only, use platform: rgb and drop the white channel.

ESPHome → HA:

• Creates light.living_room_led_strip
• Fully supports:
  • Brightness
  • Colour (HS / RGB)
  • Colour temperature (via white channel mixing)
  • On/off, transitions

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5. Home Assistant Usage (ESPHome)

Once the ESP32 is online, HA will auto-discover the light.

5.1 Lovelace Card

type: light
entity: light.living_room_led_strip
name: TV Backlight

Or as part of an entities card:

type: entities
entities:
  - light.living_room_led_strip

You can:

• Pick colours from the wheel
• Adjust brightness
• Use it in scenes and automations like any other HA light.

5.2 Simple Automation Example

Turn strip on at sunset in warm white:

automation:
  - alias: "TV Backlight at Sunset"
    trigger:
      - platform: sun
        event: sunset
        offset: "-00:15:00"
    action:
      - service: light.turn_on
        target:
          entity_id: light.living_room_led_strip
        data:
          brightness: 150
          color_temp: 370   # warm-ish

Turn off at 01:00:

  - alias: "TV Backlight Off at Night"
    trigger:
      - platform: time
        at: "01:00:00"
    action:
      - service: light.turn_off
        target:
          entity_id: light.living_room_led_strip

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6. ESPHome vs WLED – Which One Should I Use?

Both ESPHome and WLED work very well with Home Assistant, but they have different strengths.

Below is a practical comparison, specifically for 12V RGB/RGBW strips (non-addressable).

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6.1 ESPHome – Pros & Cons

Pros

• Single firmware for everything: you already use ESPHome for sensors, relays, etc.
• All configuration in YAML, versionable and consistent across devices.
• Can combine in one node:
  • LED control
  • Sensors (e.g. temp behind TV, ambient light)
  • Buttons (physical switches)
• Fine-grained integration with HA:
  • Native light entity
  • Additional outputs, sensors, binary sensors, etc.

Cons

• Effects support is basic compared to WLED (simple transitions, a few effects via addressable and effects:, but not dozens of fancy animations).
• No nice built-in web UI for live effect selection.
• If you want heavy effect usage (party / holiday lights), you’ll have to configure manually or move to WLED.

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6.2 WLED – Pros & Cons (for this use case)

WLED is a dedicated LED firmware, mostly targeting addressable LEDs (WS2812B, SK6812, etc.), but it also supports “analog” RGB/RGBW (like 12V strips with MOSFETs).

Pros

• Fantastic web UI with:
  • Dozens of effects, palettes, playlists
  • Intensity, speed, presets
• Excellent Home Assistant integration (WLED integration):
  • light entity
  • Effect selection directly from HA
  • Sync with other WLED instances
• Very easy to install using WLED web flasher

Cons

• Firmware focused purely on lighting:
  • Harder to “merge” with your sensor/relay logic.
  • If the same ESP32 also needs to be a sensor node, it’s messier.
• Configuration is web-based, not YAML; harder to keep in Git with the rest of your ESPHome configs.
• Overkill for a “set colour once and forget” indirect light.

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6.3 Summary Table

Feature	ESPHome RGB/RGBW	WLED (Analog RGB/RGBW)
Config style	YAML	Web UI / JSON presets
HA integration	Native ESPHome API	WLED integration + light entity
Effects	Basic	Extensive (dozens)
Best for	Mixed nodes (sensors + LEDs)	Pure lighting, effects-heavy setups
Version control	Very easy (YAML)	Possible but more manual
Learning curve	Easy if you already use ESPHome	Easy for non-coders via web UI

Rule of thumb:

• Use ESPHome if:
  • This ESP32 also handles sensors, relays, fans, etc.
  • You want everything consistent in YAML.
  • You mainly want static colours and simple transitions.
• Use WLED if:
  • The ESP32’s only job is LED effects.
  • You care about rich, configurable animations.
  • You want an easy UI for non-technical family members.

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7. Bonus: Basic WLED Wiring for 12 V RGB Strip

The hardware wiring for WLED in analog mode is the same:

• ESP32 PWM pins → MOSFET gates
• MOSFETs → strip channels
• 12 V PSU → strip + common ground

In WLED’s web UI:

1. Go to Config → LED Preferences
2. Set “LED Outputs” to Analog
3. Assign pins:
   • Red GPIO 25
   • Green GPIO 26
   • Blue GPIO 27
   • White GPIO 14 (for RGBW)
4. Select “RGBW” mode if needed.

Home Assistant will auto-discover the WLED instance and create light.wled_xxx.

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8. Practical Notes

• Logic-level MOSFETs only: ensure the chosen MOSFET fully turns on at 3.3 V gate drive.
• Strip power: feed 12 V directly to strip, not through ESP32 or USB.
• Fusing: add a small inline fuse on the 12 V output to the strip, especially for long runs.
• Ground loops / noise: always tie ESP32 GND to PSU negative at a single solid point.
• Heat: MOSFETs can run warm at high currents – mount them so they can dissipate some heat.

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Final Thoughts

For a Home Assistant–centric home where you’re already using ESPHome for sensors and relays, an ESPHome-based RGB/RGBW controller is usually the cleanest choice: one YAML file, one firmware, fully integrated.

If you’re building a pure lighting / effect-heavy installation (TV backlight, party lights, holiday decorations), WLED on an ESP32 plus MOSFETs is hard to beat.

The good news: the wiring is almost identical. You can even start with ESPHome and later reflash to WLED (or vice versa) without changing the hardware.