Overview
Silicon Labs RAIL (Radio Abstraction Interface Layer) provides an intuitive and easily-customizable radio interface that is designed to support proprietary or standards-based wireless protocols. RAIL allows customers to adopt the latest RF technology without sacrificing the previous development investment and future-proofs the code migration to future EFR32 ICs. The unified radio software API abstracts the significant number of hardware registers and complexity of the lower-level radio block, allowing customers to focus on their proprietary wireless application development instead of mastering device-specific details.
RAIL Software Features and Benefits
| Features | Benefits | |
|---|---|---|
| Unified Radio API across SoCs | Application portability; Simple APIs for complex radio register level configurations | |
| Multi-Protocol and Multi-PHY Support | Develop innovative applications like Dynamic Multi-Protocol BLE + Proprietary | |
| Ready to use and customizable PHYs | Simplify & shorten the development process with dozens of validated PHYs | |
| Support for WM-BUS, SigFox and Wi-SUN | Develop standard-based stacks using Silicon Labs hardware | |
| Support for low power energy modes | Develop very low power battery operated applications |
RAIL SDK Specification Support
Sample Applications
RAILtest
Range Test
Simple TRX
Empty Example
Duty Cycle
Energy Mode
Light and Switch
Wireless M-bus Meter/Collector
Enablement
Bootloader
In-Field Upgrade
Secure Boot
Signed Upgrade Images
Encrypted Upgrade Images
RTOS
Micrium
Command Line Interface
Development Tools
Simplicity Studio IDE
Radio Configurator
Network Analyzer
Energy Profile
Application Builder
Hardware Configurator
Supported Toolchains
IAR Embedded Workbench for ARM
GCC (The GNU Compiler Collection)
Mobile Apps
DMP BLE+RAIL Mobile App for iOS and Android
Downloads
Download and Install Simplicity Studio
Get up and running quickly with precompiled demos, application notes and examples. Use advanced tools including energy profiling and network analysis to optimize your wireless systems. Choose your software package below.
GitHub
Silicon Labs wireless IoT SDKs and code examples are also available for download on GitHub.
VS Code IDE Support
In addition to the Simplicity Studio IDE, we also support VS Code that can be used in companion with all of our unique development tools.
Related Software
Tech Docs
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Simplicity SDK
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Gecko SDK
Simplicity SDK Release Notes (2024.12.0)
Latest Release - Q2/2025 (April 2025)
RAIL SDK Version 2.18.2.0
- RAIL Tutorial moved to docs.silabs.com, view tutorial here
- RAIL SDK supported on BRD4276A radio board with EFR32FG25 and SKY66122-11 frontend module for high TX power applications
- Improved RangeTest Sample Application to fully support multi-PHY configurations and added new feature to control measurements on RX side – in alpha quality
- Sigfox TX PHYs and RX PHYs supported on EFR32FG23 and EFR32FG28 parts for EU and NA region
| Release | Date | Release Notes |
|---|---|---|
| 2025 | 2025/04 | Version 2.18.2.0  |
| 2025/02 | Version 2.18.1.0 |
|
| 2024 | 2024/12 | Version 2.18.0.0 |
Gecko SDK Release Notes (4.4.6.0)
Latest Release - Q1/2025 (February 2025)
Proprietary Flex Version 3.7.6.0
Rail Apps and Libraries
- Connect OFDM support for some applications
- EFR32xG28 Proprietary 2.4 GHz 15.4 Standard PHY support
- Added hardware support: MG24 QFN40, EFRBG22-E, EFR32xG28 Explorer Kit
Connect Apps and Stack
- SUN-FSK and SUN-OFDM support
- Long message reception and transmission
| Release | Date | Release Notes |
|---|---|---|
| 2025 | 2025/02 | Version 3.7.6.0 |
| 2025/01 | Version 3.5.7.0 |
|
| 2024 | 2024/10 | Version 3.7.5.0 |
| 2024/08 | Version 3.7.4.0 |
|
| 2024/07 | Version 3.5.6.0 |
|
| 2024/05 | Version 3.7.3.0 |
|
| 2024/04 | Version 3.7.2.0 |
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| 2024/03 | Version 3.6.3.0 |
|
| 2024/02 | Version 3.7.1.0 |
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| 2024/01 | Version 3.5.5.0 |
- AN1254: Transitioning from the v2.x to the v3.x Proprietary Flex SDKv0.212/2/2020
- AN700.1: Manufacturing Test Guidelines for the EFR32v0.29/2/2022
- AN1113: Porting RAIL Applications to RAIL Version 2.xv0.48/17/2020
- AN1119: Using RAIL for Wireless M-Bus Applications with EFR32v1.26/6/2024
- AN1253: EFR32 Radio Configurator Guide for Simplicity Studio 5v0.712/13/2023
- QSG168: Proprietary Flex SDK v3.x Quick-Start Guide v0.66/8/2023
- UG103.01: Wireless Networking Application Development Fundamentals v1.53/6/2022
- UG103.07: Non-Volatile Data Storage Fundamentals v1.73/6/2022
- UG409: RAILtest User's Guide v4.22/14/2024
- UG103.19: Machine Learning in Embedded Applications Fundamentals v0.14/26/2022
- UG103.6: Bootloader Fundamentals v2.17/27/2023
- Flex SDK Release Notesv2.5.27/21/2020
- Proprietary Flex Release Notesv3.3.1.01/28/2022
- Proprietary Flex Release Notesv2.7.1.07/21/2020
- Proprietary Flex Release Notesv2.7.8.010/29/2020
- Proprietary Flex Release Notesv2.7.3.07/21/2020
Community & Support
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