Bluetooth® connects us to the world through our smartphones. We can interface with door locks, thermostats and even our cars. But are all bluetooths the same? Do you unlock your car using the Bluetooth you use to stream music from your phone to your smart speaker?
The answer is “yes”, it may be “no”. Bluetooth® Low Energy is a standards-based protocol that enables interoperability between different devices and products, with optional additional features to extend the capabilities of more complex solutions. When choosing the right Bluetooth solution for an application, there are three basic aspects to consider: software capabilities, hardware, and cost.
Software function
There are two important technical details to consider on the software side:
Which core specification can a device be certified to?
What feature sets does the device support?
The core specification defines the basic functionality of Bluetooth® Low Energy. These features must work to create an interoperable experience for consumers when their phones interact with products made by hundreds of different companies. These features are required to release BTX.X certified products such as BT5.0. Additional features associated with different Bluetooth® Low Energy specification versions (outside of the core specification) are optional. For example, BT5.0 adds high-speed mode, long-range mode, and extended advertising, but your app doesn’t have to support these features to be BT5.0 certified. Likewise, BT5.1 added orientation as an extra feature.
hardware
The hardware that runs the Bluetooth stack also varies widely. Some basic devices have a single core that can be used for both application and RF functions, while integrated devices provide an application core and a microcontroller (MCU) core, respectively. Additionally, one-time programmable devices are based on read-only memory and cannot be updated after programming, while flash-based devices can be upgraded thousands of times, even wirelessly in the field.
If you are aiming to design a scalable and reliable application, it is important to evaluate cost-effective, high-quality devices with a variety of hardware options including integrated application MCU and flash memory architectures. Such evaluations allow you to choose the right features at the right price.
The table below shows some of the key features of Bluetooth® Low Energy devices in TI’s portfolio.
Certain applications, such as wearables, require the smallest possible size to avoid intrusion. Other applications require higher performance, such as longer distances or multi-protocol operation, and are insensitive to size. TI’s portfolio offers hardware options that scale across memory footprint, performance, Bluetooth capabilities and packaging. For example, the smallest form factor is the CC2640R2F-Q1 in a 2.7mm x 2.7mm WCSP package. The most cost-effective product is the CC2640R2L in a 5mm x 5mm QFN package. For multi-protocol support and long-distance transmission, the best choice is the CC2652P and its integrated power amplifier.
cost
When designing a Bluetooth® Low Energy product, choosing the right features is as important as considering the price. Devices in the SimpleLink portfolio come in a variety of price, feature and performance options. The latest device in TI’s Bluetooth platform, the CC2640R2L, is a flash-based Bluetooth wireless system-on-chip that starts at $0.85. Additionally, the CC2652RB saves system cost by eliminating the need for an external crystal. It integrates this critical system component into the device’s package, resulting in an average overall system savings of $0.10 to $0.20 compared to crystal-based solutions.
Remember – all Bluetooth is standard, but not identical. When designing an application, it’s important to cover the basics of Bluetooth (software capabilities, hardware, and cost) so that you can find the right solution whether you’re unlocking your car or setting the room temperature. The TI portfolio covers all bases by offering a variety of software options (BT5.0, positioning, coexistence) and hardware options (memory, packaging, performance).