When it comes to putting devices in hard to reach places, power consumption plays a major role. Depending on the application, the device needs to either operate independently for a very long period of time or needs to be sufficiently small so as to not be intrusive, which requires very low power usage. The number of low power applications is extensive and growing all of the time, making this a high demand area. And given the complexity of the solutions, it is also a challenging one.
Remote Locations
The first application for low power devices is in areas that are hard to reach in the first place or that do not have power sources readily available. The most extreme example of this is the Mars Rovers. Once the rovers were launched and landed on the red planet, there was little chance of someone being able to change the batteries to keep them going. They relied on initial battery power and supplemented it with solar power. In order to perform the research and analysis, and transmit the results back to Earth, ultra low power techniques were implemented.
A little closer to home, many industrial applications are not easily accessible but still need electronic devices, such as sensors, to monitor the situation. While some of these sensors rely on alternative power generators, such as piezoelectric, solar, or thermal electric, the need to maximize the power that is created still exists.
Medical Applications
The medical arena is one area where low power is a necessity. The US accounts for an estimated 60% of the world market for medical procedures with an annual average growth rate of 7.2%. The demand for minimally invasive surgery, which accounts for 80% of all surgeries, is on the rise, so smaller devices were created to enable surgeons in the operating arena.
As an example, a typical pacemaker functions only when necessary to prolong the battery life. However, at some point the battery needs to be changed and the entire pacemaker is replaced. Currently, around 100,000 pacemakers are replaced annually at a cost of about $10K each. If a pacemaker could last even one year longer, that would result in a considerable saving each year, especially as the population ages and more pacemakers are implanted.
A second example that requires ultra low power is a camera pill. As the name implies, this is a small pill shaped camera. While the application is relatively new, it is expected to generate over $500M in revenue in 2013 with a growth rate of 5%. While the dimensions vary from company to company, it is not unheard of to see a 22mm x 11mm "pill", which is no larger than an extra strength Advil capsule. The camera pill can take a few pictures every second for around 8 hours. However, as technology enables lower power consumption, more pictures can be taken in the same amount of time to provide better diagnostics as it works its way through your system.
Consumer Product
It is not only niche markets that can benefit from ultra low power devices. As consumer devices get smaller and smaller, the capabilities seem to grow exponentially. This means that the batteries have less space but must be able to last for a longer amount of time before needing to be recharged. Can you imagine your iPhone only lasting 1 hour on a charge?
Low power techniques are implemented in almost every device we use. While not "ultra" low power, compared to some of the other applications discussed, five years ago they would have been considered such. I am sure that when we look back 5 years from now, these techniques will be considered extremely conservative on power consumption.
Greg Quirk has been a technical writer since 2004 focusing on semiconductor components, consumer devices and business trends. He has written numerous articles for industry publications and presented at technical conferences. His expertise has been sought by the financial community on multiple occasions to predict design-wins in popular consumer products.
By Greg Quirk, Mouser Electronics