Is HLK-LD2420 24GHz Presence Radar Compatible with Home Assistant (ESPHome)?
Electrical Specifications
Always confirm pin assignments against the manufacturer datasheet before wiring.
Compatibility Overview
Budget 24GHz mmWave presence module of the LD2410 family; newer firmware talks at 115200 baud where pre-v1.5.3 units ship locked to 256000.
Typical UART Wiring Reference
Standard UART signal names. This is a bus reference, not a pinout for this specific board — check the silkscreen and datasheet for its actual pin order.
Reference circuit only. A shifter is needed when the host and peripheral run at different logic levels — check both datasheets to confirm whether this applies to your pairing.
Technical Specification Matrix
| Feature / Attribute | Specification / Status |
|---|---|
| Hardware Protocol | UART Serial / 3.3V |
| Bridge Required | NO |
| Border Router Needed | None |
| Hardware Capabilities & Peripherals | Presence State Moving Target Distance (cm) Note: these entities come from the ESPHome configuration you flash — each one needs its matching component in that YAML before it appears. |
| Pairing Complexity | Intermediate |
| Factory Reset Instruction | Hold BOOT button for 3s. |
Wire, Flash, Adopt, Check
Wire it up
Follow the bus reference above. The host pins in the configuration are defaults — any free GPIO of the right kind will do, as long as the YAML names the pin you actually used.
Flash the configuration
Create a new device in the ESPHome dashboard (the Home Assistant add-on) and paste the configuration below into it, or save it as emb_esp32_ld2420_esphome.yaml and run esphome run emb_esp32_ld2420_esphome.yaml. The first flash goes over USB. If it is not detected, hold BOOT button for 3s to put it in download mode. Every update after that is over the air.
Adopt it in Home Assistant
Settings → Devices & Services. A node on the same network shows up as a discovered ESPHome device within a minute of joining Wi-Fi; choose Configure and enter the API encryption key from your secrets.yaml. If discovery does not find it, add the ESPHome integration by hand with the node's IP address.
Check it works
The entities on this page appear under the device in Home Assistant and update at the configured interval. The ESPHome log (Logs in the dashboard, or esphome logs) reports the setup of each component and any bus scan results at boot.
ESPHome Configuration
Starting configuration for HLK-LD2420 24GHz Presence Radar on ESP32. Untested on hardware — verify wiring and pins against your own board.
# ESPHome configuration for HLK-LD2420 24GHz Presence Radar
# Host: ESP32. Pin numbers below are host-side defaults — any free
# GPIO will do, and you should change them to match your own wiring.
esphome:
name: emb_esp32_ld2420_esphome
friendly_name: "HLK-LD2420 24GHz Presence Radar"
esp32:
board: esp32dev
framework:
type: esp-idf
logger:
api:
encryption:
key: !secret api_encryption_key
ota:
- platform: esphome
password: !secret ota_password
wifi:
ssid: !secret wifi_ssid
password: !secret wifi_password
uart:
rx_pin: GPIO16
tx_pin: GPIO17
baud_rate: 115200
# Firmware before v1.5.3 ships locked to 256000 baud — if the log shows
# nothing at 115200, change baud_rate above and reflash.
ld2420:
binary_sensor:
- platform: ld2420
has_target:
name: "Presence"
sensor:
- platform: ld2420
moving_distance:
name: "Moving Distance"
Before you flash:
the !secret values come from your
secrets.yaml, and the GPIO numbers are host-side
defaults rather than properties of this part — change them to match how you actually wired it.
Report a Pinout Error or Submit Tested Code Snippets
Found a pin mapping quirk or built a custom ESPHome YAML driver for HLK-LD2420 24GHz Presence Radar? Submit a pull request or report corrections to our index.