This posting will be an initial discussion on creating energy efficient products. There is no silver bullet for energy reduction meaning that you can’t attack the power problem on a single front. Power is distributed and should be optimized at all levels of the system for the system to be energy efficient. The teams in Freescale are working in multiple areas to enable low power products. These areas are highlighted in the Freescale Energy Efficiency Target
Figure 1: Freescale Energy Efficiency Target.
Process Technology
At the lowest level, the process technology is the foundation of integrated circuits. As the digital process technology continues to scale to smaller dimensions, the leakage current is increasing exponentially which means leakage is becoming a very big problem for components made in deep sub-micron CMOS technologies.
Packaging
Packaging and PCB design can detrimentally impact product power due to the large parasitic capacitances, inductances, and impedances that the circuit IOs must drive to transfer information between components.
Circuit and Module Design
For power reduction in circuit and module designs, we target both active and static power savings. In order to reduce active power, we use techniques such as clock gating or dynamic voltage and frequency scaling in our products. In order to reduce static power, we reduce the voltage or use some form of power gating on high leakage modules. These techniques have trade-offs and many require software to enable these techniques in a platform.
Component Design
The architecture and implementation of components such as microprocessors, application processors, baseband processors, power management ICs, and RF components will dictate the power of the component. We work hard to ensure that only modules to enable the required use cases are used at the lowest frequencies to meet the performance targets.
Platform Design
Platforms are made up of components and software to form an end product. The components you select and how you connect them up for a final product can have a significant impact to the system power.
System and Application Software
Software plays a key role in power consumption. Energy in your system can be squandered away if your software does not take advantage of all power reduction techniques implemented within the hardware.
Tools and Modeling
Tools and modeling are key to understanding where the power is being consumed in a system. This understanding allows us to identify areas in the hardware and software to optimize and to design out the power of the system.
In future posts, I will discuss each area in more detail and provide example techniques that can be employed to reduce power of the overall system. Please let me know if there are any specific topics regarding low power that is of interest and that I may address in a future post.
- Chris
