1. Introduction
The PDDAXLQUE DX-LR20-433Mmz-SET is a development kit featuring the Semtech LLCC68 chip, designed for long-range, low-power wireless communication using LoRa spread spectrum technology. This kit operates in the 410-475MHz/433MHz frequency band and offers enhanced performance, extended transmission distance, faster data rates, and lower power consumption compared to previous generation solutions. It includes features such as wake-on-radio, carrier sensing, communication encryption keys, and adjustable packet length settings, making it suitable for a wide range of IoT and industrial applications.
2. Product Overview
2.1 Key Features
- Chipset: Integrates Semtech LLCC68 chip for advanced LoRa capabilities.
- Frequency Band: Supports 410-475MHz / 433MHz communication.
- Transmission Distance: Achieves up to 8 km in open environments.
- Output Power: Features 22 dBm output power for robust signal strength.
- Interface: Programmable via SPI interface; requires user-developed firmware.
- Crystal Frequency: 32 MHz.
- IO Compatibility: TTL level output compatible with 3.3V–5V IO port voltage.
- Enhanced Protection: Equipped with an RF shielding cover for strong interference resistance, enhanced electrostatic protection, and excellent EMC performance.
- Advanced Functions: Supports wake-on-radio, carrier sensing, communication encryption keys, and adjustable packet length settings.
2.2 What's in the Box
The DX-LR20-433Mmz-SET development kit typically includes the following components:
- 2 x DX-LR20-433 Modules
- 2 x Antennas
- 24 x Dupont Wires
Image: Components included in the DX-LR20-433Mmz-SET development kit.
3. Setup Guide
3.1 Safety Precaution: Antenna Connection
Before powering on the module, it is crucial to connect the antenna. Operating the module without an antenna can prevent the radio frequency power from being properly dissipated, which may cause damage to the internal circuitry.
Video: DX-LR20/30 Product Quick Verification Tutorial. This video demonstrates the initial setup and verification process, including connecting the antenna and powering on the modules.
3.2 Driver Installation (Windows)
This feature has been verified on Windows 7 through Windows 11 systems. If you are using another operating system (such as macOS or Linux), please seek alternative tools or methods.
- Download the CH340 Driver from the official DX-SMART Google Drive or website (links provided in Section 6).
- Run the installer (e.g.,
CH341SER_drive.EXE) and follow the on-screen instructions to complete the installation. If the driver is already installed, you may skip this step.
3.3 Serial Tool Configuration
- Download and run the serial debugging tool, "UArtAssist", from the provided resource package (available on the official DX-SMART Google Drive or website).
- Connect both DX-LR20 modules to your computer via USB.
- In UArtAssist, select the corresponding serial port (COM port) for each module.
- Set the baud rate to 9600 for both modules.
- Click the "Open" port button for both modules.
- Press the "Reset" button on each module. The debugging tool should then receive raw information from the modules, indicating successful communication.
4. Operation
The DX-LR20 module utilizes an SPI interface for communication and requires custom firmware development by the user. Detailed technical documentation, sample programs, and reference design schematics are available to assist with development.
4.1 Frequency Band Selection
The DX-LR20-433Mmz-SET operates in the 410-475MHz frequency range. LoRa solutions primarily use unlicensed ISM frequency bands, and available frequency bands and center frequencies vary by region. Users must verify local RF spectrum regulations prior to operation.
Image: Global license-free ISM bands and regional frequency allocations.
4.2 Pin Definitions
Refer to the detailed pin definitions for proper integration with your microcontroller unit (MCU). The module provides TTL level output compatible with 3.3V–5V IO port voltage.
Image: LR20-SMD Pin Definition Diagram.
5. Specifications
| Attribute | Value |
|---|---|
| Brand | PDDAXLQUE |
| Model Number | DX-LR20-433Mmz-SET |
| Chip | Semtech LLCC68 |
| Frequency Band | 410-475MHz / 433MHz |
| Output Power | 22 dBm |
| Transmission Distance | Up to 8 km (open environment) |
| Interface | SPI |
| Crystal Frequency | 32 MHz |
| IO Port Voltage | 3.3V–5V compatible |
| Operating Temperature | -40°C to +85°C |
| Module Size | 35.6mm (L) x 18mm (W) x 3.2mm (H) |
Image: LR20-433M22SP Key Features and Specifications.
6. Technical Support & Resources
PDDAXLQUE provides comprehensive technical support and resources to assist users with the DX-LR20 development kit. As a manufacturer, we are committed to helping you solve any problems you encounter.
6.1 Available Resources
We offer a complete information package, including:
- Technical documentation
- Sample programs
- Module package drawings
- Reference design schematics
- Development and testing tools
These resources are available on our official website and Google Drive:
- Official Website: en.szdx-smart.com
- Google Drive: https://drive.google.com/drive/u/0/folders/1ThDbees2KQ4oRbOyQuTkcjaJWZ9tdry7
Image: Overview of available technical documentation and tools.
6.2 Contacting Support
If you have any questions or require assistance, please contact us directly. We also offer OEM and ODM services for customized solutions.
7. Maintenance
To ensure the longevity and optimal performance of your DX-LR20 modules, keep them in a clean, dry environment. Avoid exposure to extreme temperatures, humidity, or corrosive substances. Handle the modules with care to prevent physical damage.
8. Troubleshooting
If you encounter issues with your DX-LR20 development kit, consider the following:
- No Power Indicator: Ensure the USB cable is securely connected and the power source is active.
- Communication Failure: Verify that the antenna is correctly attached before powering on. Check that the CH340 driver is installed and the serial port settings (COM port, baud rate) in UArtAssist are correct. Ensure the modules are properly reset after opening the serial port.
- No Data Transmission: Confirm your custom firmware is correctly loaded and configured for the desired communication protocol. Refer to the technical documentation for sample programs and debugging guides.
- Interference Issues: The module features an RF shielding cover for interference resistance. Ensure proper grounding and avoid placing the module near strong electromagnetic sources.
For persistent issues, please consult the detailed technical documentation available on our official website or Google Drive, or contact our technical support team.
