Nordic Power Profiler Kit allows easy and affordable power measurement during embedded software development with nRF51 and nRF52 Bluetooth low energy SoCs

2016-10-13
The Power Profiler Kit is a development tool designed to allow embedded software engineers to profile power consumption of embedded solutions during development. This can be done easily at a cost low enough to allow every engineer to have a kit on their desk


Nordic Semiconductor today announces the availability of its ‘Power Profiler Kit’, a development tool comprising PC-based software and an extension board for the company’s nRF51 and nRF52 Series Development Kits (nRF51 DK and nRF52 DK). Targeting software and hardware engineers designing embedded solutions, the low-cost Power Profiler Kit development tool provides a simple method to measure dynamic power consumption in embedded solutions.

A simple ampere meter is insufficient for obtaining a comprehensive overview of the power consumption of embedded devices when such devices continuously change between low power- and active-modes. In addition, precise power consumption measurement becomes even more difficult as duty cycle decreases. In some Bluetooth® low energy (previously known as Bluetooth Smart) applications power mode changes are frequent and the duty cycle may be less than 1 percent, making the use of standard power measurement tools impractical.

The Power Profiler Kit overcomes these challenges and is designed to be used for the entire wireless product development cycle - from proof of concept to final product completion. The low cost of the Power Profiler Kit allows every engineer working on a project to have their own unit, something that’s not practical with a lab-grade power profiling tools. The PC-based tool also makes it easy to detect flawed- or non optimized-software because it clearly indicates unusually high power consumption, for example from active modules that the software should have disabled.

During the initial phase of product design, the kit can be employed to measure the power consumption of the nRF51 or nRF52 Series Bluetooth low energy System-on-Chip (SoC) while the prototype product is developed on the nRF51 DK and nRF52 DK. For later stages it is possible to measure the power consumption for the entire design on the final PCB. Continuous power consumption measurement at all stages of software development ensures power problems are identified early in the engineering cycle making it easier to avoid time-consuming revisions of code at a later stage.

The Power Profiler Kit includes an advanced auto-ranging analog measurement circuit to support high speed current measurement across a large dynamic input range. The kit supports an input range from 0 to 70mA with a resolution of just 0.2µA for the lowest range. Sampling is performed every 13µs in order to ensure even the shortest periods of activity are captured.

The PC-based software supporting the Power Profiler Kit provides several ways of assessing the power consumption, both instantaneous and averaged over a set time period. The user can set up the kit to take readings over a period of up to 20 seconds, while simultaneously zooming in on a millisecond interval of interest. Over both these time periods the user can select points for instantaneous measurement as well as areas over which to average. Measured data can also be exported for post processing.

The Power Profiler Kit PC software is based the Python programming language and is delivered via an installer that includes all the required Python scripts. The use of Python enables non-expert programmers to easily modify and customize software. The software output can generate logs that can be processed directly by other tools.

“Many customers repeatedly tell us that they find power consumption measurement difficult because ampere meters are not able to measure precisely across the large dynamic range and low duty cycle exhibited by Nordic’s nRF51 and nRF52 Series SoCs,” explains Pål Kastnes, Technical Marketing Manager with Nordic Semiconductor.

“Combined with the high cost of lab tools for accurately measuring power consumption, this difficulty often means tests are conducted infrequently and late in the software development process. This all too often leads in significant development in the wrong direction before excessive power consumption is detected. Providing an affordable development tool to mitigate this challenge is just one of the ways Nordic helps customers accelerate their development processes,” adds Kastnes.