Bluetooth Low Energy (LE) is gaining support from an increasing number of component and module suppliers. No wonder: this ultra-low power, short-range RF technology will offer a simple means to connect any slave device to, in future, billions of smartphones, tablets and laptop computers.
The fact is, however, that electronics design engineers are already well served by a wide choice of industry-standard, short-range RF technologies, such as ZigBee and Wi-Fi. So does Bluetooth LE have an advantage over these existing standards?
In fact it does, provided the application requires the transmission of short pulses of data and long battery life. But design engineers will only gain the advantages of using Bluetooth LE if they make the right choice of components for their application and market.
Something new, something old
Despite sharing the ‘Bluetooth’ name with Classic Bluetooth, Bluetooth LE is different in many important ways. Classic Bluetooth is designed to provide an always-on wireless pipe for streaming audio and other streamed data, and supports data rates of up to 3 Mbps. It also features a complex protocol stack, required in part to support the complicated methods for establishing and maintaining a connection between two paired devices.
Bluetooth LE has completely different attributes: it features a simple protocol stack which makes and breaks connections extremely fast, enabling short pulses of data to be transmitted intermittently. It achieves very low power consumption – months or years of operation on a single coin cell – because its mode of operation enables the device to be in a deep sleep mode, with the radio switched off, for most of the time.