We live in an era where saving energy is a topic that receives considerable attention. For design engineers, there are many different motivations for saving energy from your company being able to claim your newest gizmo has longer battery life than any of its competitors to conserving natural resources to reducing the air pollution and greenhouse gas emissions associated with generating electricity. Until recently, reducing energy usage in electronic circuit designs was primarily a concern for designers of battery power products. Today, legislative restrictions on energy usage are covering more and more types of products and the marketplace pressures for reducing energy usage are impacting nearly all types of electronic products from consumer electronics to IT equipment and even industrial and manufacturing equipment. In our “instant on” world where few things are ever really turned completely off, the energy a device uses when it is doing nothing is becoming more important than the energy it uses while operating. These so called phantom loads drive megawatts of electricity generation daily and are squarely in the sights of legislators writing energy efficiency regulations.
There are a number of ways to reduce the energy usage of your designs. Your hardware design will establish a baseline for the minimum amount of power your product consumes but for many types of products the firmware will really determine the overall power usage. Sophisticated software power management schemes that were once mainly employed in laptop computers and cell phones are being implemented in increasingly less complex products to reduce power usage. However, simply selecting the latest low power micro and implementing sophisticated power management is the “big stick” approach to power savings. There are dozens of hardware design decisions and hundreds of firmware design decisions that will either enhance or sabotage your power saving efforts. The accumulation of these smaller savings can often save more power than the big stick savings.
There are many things to consider in your designs, some will have big pay-offs in power savings but . The over-riding theme in the tips and techniques I will present is anything your design does that it doesn’t need to do is wasting energy. That sounds very obvious but many of the things we do in our designs that waste energy often are not obvious. Some of the information that will be presented can be found in other places on the Internet but newcomers to low power design may not have seen it. Many of the tips and techniques that I’ll discuss were learned through years of developing low power products. I look forward to helping with your power saving efforts.