Bluetooth Developer

What is Bluetooth Low Energy?

The Bluetooth specification's 4.0 version introduces Bluetooth Low Energy (LE), which incorporates a wholly new Link Layer specification. Bluetooth LE enables two devices to exchange data sparingly to conserve energy, while also facilitating the transmission of a series of packets for substantial data transfer. Additionally, it includes support for broadcasting data through advertisements. 

Bluetooth LE Architecture

At Silicon Labs, we are dedicated to delivering the best Bluetooth solutions for our customers. Our Bluetooth stack supports long range, 1M, and 2M PHY to enable devices to communicate over longer distances or at higher speeds. Our Bluetooth stack also supports direction finding and other locationing services enabling applications such as indoor navigation, asset tracking, and proximity detection. Moreover, our Bluetooth devices can operate in SoC, NCP, and RCP mode, three different modes of integration and functionality that offer different trade-offs between cost, performance, and flexibility. Whether you need a low-power, high-performance, or versatile Bluetooth solution, we have you covered.

Point-to-Point Connections

Just like Bluetooth Classic, Bluetooth LE can be used to connect two devices to exchange data. Bluetooth LE primarily supports data exchange by reading and writing characteristics in the GATT database, but bulk data transfer is also possible. Connections support 125k/500k/1M/2M symbol rate to let you choose between high range (hundreds of meters) and high data rate (up to 1.6 Mbps).

Location Services

While Bluetooth beacons can be used for asset tracking, the accuracy of the tracking is usually low (meters). Bluetooth 5.1 introduced a special beacon that brings submeter accuracy when it comes to location finding. This can be used for accurate tracking of assets. 

Bluetooth beacons are periodically sent short packets that can be used to signal the presence of an asset and send a limited amount of data (such as an ID). Bluetooth beacons are used in asset tracking, geofencing, product tagging and similar use cases.

Bluetooth Mesh

Even though the Bluetooth specification does not define a network layer, the multi-connection support lets you connect one device with many more, forming a star topology. Bluetooth LE Dual Topology even lets you make an extended star topology. You only have to take care of forwarding data between the nodes. If you need a real Bluetooth LE based network, check out our Bluetooth Mesh solution.

What’s New with Bluetooth 5.4

Broadcasting Data (PaWR)

Bluetooth LE advertisements let you send data to an unlimited number of devices. With extended advertisements you can send up to 1650 B at once, and choose to repeat or change the payload at any time. Periodic Advertisements eliminate the need for continuous scanning and Periodic Advertisements with Responses (PAwR) make it possible to transfer data to thousands of devices with acknowledgements.

Electronic Shelf Labels

Bluetooth 5.4 defines all features that are needed for extra low power data exchange between Access Points and thousands of ESL tags, and it aims to be the de-facto standard for ESLs.

Bluetooth Developer Journey with Silicon Labs

Silicon Labs can accelerate the development of Bluetooth devices, starting by outlining each step in the process and helping you along each stage of your project. We are here to simplify your development journey and help you get your devices to market faster and more efficiently.
We have outlined below three key stages of the Bluetooth Developer Journey, along with what is required to successfully complete each stage.

Getting Started
Deploy Product
  1. 1. Buy Kit: Examples & Hardware
  2. 2. Simplicity Connect Mobile App
  3. 3. Create User Accounts
  4. 4. Set Up Development Environment
  5. 5. Explore Demos
  1. 1. Create a Sample Application
  2. 2. Develop and Debug
  3. 3. Test and Iterate
  1. 1. Qualify Product
  2. 2. Manufacture Product

1. Buy Kit: Hardware and Examples

Silicon Labs offers several Bluetooth development kits ranging from ultra-low-cost, small form factor prototyping platforms to compact, feature-packed development platform kits for robust networks. Based on the demos you would like to explore, select which kit is the best fit for your needs below. For enabling in-depth evaluation and future development, Silicon Labs recommends choosing at least 2 development kits (2 BLE nodes). 

Kit BGM220 Explorer Kit EFR32BG22 Thunderboard Kit EFR32xG24 Dev Kit
OPN (BGM220-EK4314A) (SLTB010A) (xG24-DK2601B)
Description The BGM220 Explorer Kit is an ultra-low-cost, small form factor development and evaluation platform for the BGM220P Bluetooth Module. Thunderboard BG22 is a small form-factor, optimized development platform for adding Bluetooth connectivity to battery-powered IoT products.  The EFR32xG24 Dev Kit is a compact, feature-packed development platform. It provides the fastest path to develop and prototype wireless IoT products. 
Price $10 USD $45 USD $79 USD
Flash/RAM 512 kB / 32 kB 512 kB / 32 kB 1536 kB / 256 kB
EFR Connect Mobile App Demo Support/Coverage
Health Thermometer ✔*

 *demo - mock thermometer in the Explorer Kit

View the full list of Bluetooth development kits

Get Up and Running Quickly with Demos

Accelerate your Bluetooth development journey with our demos—Thunderboard's sensor array, health-thermometer for temperature readings, and Blinky for two-way communication. Quickly set up monitoring using your mobile phone as the client.


Support for various set of sensors that work together with an xG24 dev kit, or a thunderboard. Can be used to set-up environment (temperature, ambient light, humidity, UV, motion sensor and magnetic sensor) monitoring with mobile phone as client.


Support for a health-thermometer to get temperature values, and transfer it to a Bluetooth LE client. All our boards support this example (exception where thermometer chip is not connected). Can be used to set up temperature measurement monitoring with mobile phone as client.


Support for a two-way communication between server and client to demonstrate IO switching capabilities through Bluetooth LE. Can be used for remote switch of a relay/lamp/fan while get the status of a sensor.

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2. Simplicity Connect BLE Mobile App

Test and debug Bluetooth embedded applications quickly - including OTA updates, data throughput, and Android and iOS interoperability. Download Simplicity Connect app on your smartphone and speed up development now. 

Android/Google Play Store

iOS/Apple App Store

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3. Create User Accounts

While you wait for your Development Kit, we recommend setting up your user accounts.

Silicon Labs Account:

Silicon Labs Account: This account will offer you access to our developer community, Getting Started guides, private GitHub repositories and our Simplicity Studio development environment. You can create your account or verify access to your account here.

Silicon Labs + Matter

Join the Bluetooth SIG

To use the Bluetooth specification and qualify your Bluetooth product, you will need to be a member of the Bluetooth Special Interest Group (SIG). Visit the SIG and decide which membership level is best for you.

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3. Set Up Development Environment

We know you have many options when it comes to choosing your development environment, but we believe Simplicity Studio is the right choice for developing your device with Bluetooth. Here’s why:

  • Includes your programmer and debugger functions so you don’t have to worry about manual setup.
  • Recognizes boards you’ve purchased and identifies which sample apps you can use.

Need help setting up your environment? Our Getting Started Guide will have you up and running in no time. 

Download the Full Online Installer Version of Simplicity Studio v5:

System Requirements

Windows     Windows 10 (64-bit)
Windows 11
MacOS 10.14 Mojave
10.15 Catalina*
11.x Big Sur*
12.x Monterey*
*if trying to use the Keil 8051 or IAR toolchains, click here
Linux Ubuntu 20.24 LTS


CPU     1 GHz or better
Memory 1 GB RAM (8 GB rcommended for wireless protocol development
Disk Space 600 MB disk space for minimum FFD installation
7 GB for wireless dynamic protocol support
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4. Explore Demos

Here is a list of some additional ideas which could be easily realized with minimal coding, modifying the referenced example application as suggested below. These use cases are not provided as ready-to-go demos; instead they provide a perfect context for further evaluation.

Thermometer Client and Thermometer Server

Water Irrigation System

Based on outside temperature measured by the Thermometer example, the Thermometer Client example will open a valve to irrigate the houseplants during vacation period. GPIO handling can be seen in Blinky example.

Suggested Kits:

(*any board that has thermometer sensor)

Blinky Server and Thermometer Server

Environment and Remote Door-opener

The Thermometer example will provide the temperature data, while the Blinky example will provide the impulse to remotely open the front yard door. All can be controlled using Simplicity Connect Mobile app.

Suggested Kits:

(*any board that has thermometer sensor)

NCP Client, Thunderboard Server

Outside Environment Measurement Tool with Logging Capability to a Web-server on the PC

The Thermometer example will provide all temperature readings, while the NCP will be connected to the PC host, and PyBGAPI Thermometer Client example  will log all measurements on it.

Suggested Kits:

(*any board that has thermometer sensor)

NCP Client, Blinky Server

Garage Door Opener

Use  the Blinky example to drive the garage door opener (motor to be connected through relay), remotely using  the Simplicity Connect Mobile app, while logging the access to the garage on a PC as NCP host (through e.g. PyBGAPI). Drive the same server/actuator through two means: Simplicity Connect mobile and PC.

Suggested Kits:

NCP Client, Blinky and Thermometer Server

Shade Adjuster Based on Outside Temperature and Weather Forecast

The Thermometer example will measure outside temperature (if Thunderboard is used, the ambient light can be combined to this using the Thunderboard example) and send data to NCP. NCP host (through e.g. PyBGAPI) will command the SOC Blinky example using pre-defined algorithm that gets data from the internet to adjust the shades on the house. The Blinky will be connected to the motor of the shades. The best tool to evaluate this use-case might be to use PyBGAPI tool.

Suggested Kits:

(*any board that has thermometer sensor)

Additional Demos

Because starting application development from scratch is difficult, the Bluetooth SDK comes with a number of built-in demos and examples covering the most frequent use cases.

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1. Create a Sample Application

Developing a Bluetooth application consists of two main steps: defining the GATT database structure and defining the event handlers for events such as connection_opened, connection_closed, and so on.

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3. Test and Iterate

In this step, it is important to test your product before submitting to test labs to ensure your product will pass testing. These resources will help you ensure your product will pass testing compliance: 

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1. Qualify Product (Certification)

The Bluetooth Qualification Process promotes global product interoperability and reinforces the strength of the Bluetooth® brand and ecosystem to the benefit of all Bluetooth SIG members. Qualification helps member companies ensure their Bluetooth products comply with the Bluetooth Patent & Copyright License Agreement and the Bluetooth Trademark License Agreement (collectively, the Bluetooth License Agreement) and Bluetooth specifications.

*Login required

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2. Manufacture Product

Bluetooth DAC injection is required for end products. Silicon Labs can help simplify the DAC injection process for Bluetooth certification with our Custom Part Manufacturing Service (CPMS), keeping your private keys private – from the factory to the end user’s homes.

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Getting Started
1. Buy Kit: Examples & Hardware
2. Simplicity Connect Mobile App
3. Create User Accounts
4. Set Up Development Environment
5. Explore Demos
1. Create a Sample Application
2. Develop and Debug
3. Test and Iterate
Deploy Product
1. Qualify Product
2. Manufacture Product
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