Design_World_-_Internet_of_Things_Handbook_April_2020

34 DESIGN WORLD — EE NETWORK 4 • 2020 eeworldonline.com | designworldonline.com

Tricks of the trade for optimizing

the energy consumption of BLE

chips affect memory size, clock

speed, operating modes, and

other factors determined during

the initial design.

Emmanuel Sambuis

Silicon Lab

Selecting the right

Bluetooth Low Energy SoC

It can be challenging to optimize

Bluetooth Low Energy (BLE) applications

for minimal energy consumption. An

understanding of BLE and the underlying

system-on-chip (SoC) architecture is critical

for realizing extended battery life. Particularly

important are insights into the BLE modes of

operation (such as Advertising and Sleep).

There are different ways to minimize the

power consumption of the entire system by

providing the right inputs to the stack and

taking advantage of hardware features of

BLE SoCs.

Within Bluetooth, BLE has secured a

significant number of sockets. One of the

most critical reasons for selecting BLE in a

wireless design is its ubiquity thanks to its

large deployment in smartphones and its

ability to extend the battery life-time. Long

battery life is extremely valuable as most IoT

end nodes are battery operated.

Though it may sound obvious, the

selection of a BLE device starts with the

evaluation of its documentation. While the

initial data-mining process seems trivial, the

comparison of semiconductor device data-

sheets can quickly turn into a complicated task.

Consider, for example, the active current

in the wireless SoC’s receive or transmit

modes. Many BLE SoCs report a current

consumption of a few milliamps. For instance,

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