A paradigm shift has taken place with the introduction of digital power technology. As with many new technologies, there is resistance to change. Unfortunately, beyond the natural resistance to change, digital power solutions are also plagued by two key misconceptions.
The first misconception centers on cost. This issue will take care of itself as system designers weigh their options and realize they can now get all the benefits of digital power management for the same price as analog.
The second misconception presents the most significant obstacle for broader adoption of digital power solutions. This is the mistaken idea that digital solutions are too complex to customize into specific applications. Is the design time investment worth the effort? It could be argued that it is, but fortunately designers need not make that choice.
Digital power management solutions have emerged that shield designers from the underlying complexity of the solution. Just as PC users do not have to know the underlying code in order to use an application, power designers do not have to know how to program digital power solutions to reap their rewards. For mass adoption to occur, it requires better and more intuitive user interfaces.
The launch of the Internet browser, the Blackberry smartphone and the iPhone with their simplified, intuitive interfaces are just a few of the examples of highly successful new technologies. When the user interface becomes truly intuitive, technology reaches a mass audience.
Increasing chip-level complexity drains design time and adds development cost. In the datacom space, 36 to 40 voltage rails are appearing on a board. In the computing world, it is common for more than 20 voltage rails to operate various ASICs, memory and processor chip sets on a motherboard. This level of complexity requires fine-grained diagnostics, control and monitoring of various parameters.
The need for system-level efficiency has added even more complexity. System-level communications and monitoring require seamless interaction with the host controller, other power devices and load ICs. Unlike analog pulse-width modulation controllers, today's digital power ICs are addressing these complex system-level issues in addition to performing the basic functions of power delivery.
Nevertheless, power engineers don't want to bother with programming. So, because digital power offers unparalleled flexibility, a good graphical user interface (GUI) is required to simplify and streamline the implementation of a digital power system at both the converter and system levels.
A good GUI delivers design aid that organizes and streamlines the work flow, while not missing any important details. A good GUI is a necessity because it hides the system-level complexity and computations so that traditional analog designers can continue to work in the S-domain.
Take an example of loop compensation, the most complex task of the converter design. The analog design involves soldering and desoldering passive components several times before finalizing the design. Therefore, the analog design would take several hours or days whereas digital design using an intuitive GUI would take only a few minutes.
Digital design does not require any knowledge of Z transforms, as all the calculations are done by the GUI in the background. In short, a good GUI provides what power systems engineers are used to seeing — bode plots, timing diagrams and simplified design iteration (by eliminating external components).
A typical work flow that a power-system designer has to go through on a routine basis would involve design, simulation, hardware implementation, test/debug and release to production. A good GUI will simplify and streamline all the tasks that need to be addressed by power-system engineers. A good GUI, through an automated design wizard, guides the designers through a step-by-step design process in minimal time. The process should be nothing more than entering the design requirements and the associated parameters in the appropriate fields of the GUI.
A GUI that is intuitive and graphical is a critical tool in taking the complexity out of the designers' hands. With the emergence of such GUIs in the industry, the adoption of digital power will no longer be simply a topic of discussion; it will become a reality.
Deepak Savadatti is a semiconductor industry veteran whose product management, marketing and sales experience includes digital power startup iWatt, network security and flow classification company Hifn, Quality Semiconductor and California Micro Devices. He holds bachelor's and master's degrees in electronics and electrical/computer engineering.