Online Design for FPGA Power

Devin Crawford, PhD, Transim Technology


Cloud-based online design tools leverage the latest Internet technology

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Figure 1: High-level schematic showing the power tree for an Altera Stratix III FPGA.

The Internet has become a key resource used by engineers to obtain information. In spite of the wealth of data, the assimilation and practical application of information remains a challenge. Cloud based online design tools leverage the latest Internet technology to provide an innovative solution to help engineers efficiently address this challenge. For example, the free Arrow Embedded Systems Power Designer is an online tool that exemplifies this approach. Functional flexibility along with reasonable expense for moderate volume applications have made programmable logic commonplace in modern embedded design. The successful operation of any FPGA, however, is contingent on proper design of the power distribution network. FPGA Designers are often faced with stringent requirements for voltage stability and ripple. The challenge of designing the right power supply network for a given rail often lies outside the expertise of engineers designing products and devices, as they are primarily focused on system performance and may miss some of the nuances of power efficiencies within it. Tools like the Embedded Systems Power Designer simplify this complex task by guiding users through sequential design steps. A wealth of knowledge that would otherwise require careful examination of data sheets and application notes is built into each step. The first step in the design process is the selection of an FPGA. The supply voltage and ripple requirements automatically linked to the appropriate nets for the selected device. The current requirements for each voltage rail can then be specified. For Altera FPGAs, the tool provides an option to import data from the "Early Power Estimator" which loads current requirements based on the initial functional specifications. The supply rail voltages and pin grouping conform to values recommended in the FPGA datasheet. These standard values and the corresponding pin groups are used to generate the high-level power tree in a schematic view (see Figure 1). Input and output requirements for individual converter circuits are passed through the hierarchy to create the circuit that meets the requirements of the specific voltage rail. The topology of the regulated converter circuits as described in the part-specific application notes is used by the design tool to generate a suitable converter. Component values can be modified and cloud based simulation provides additional confidence in the design. The resulting circuit schematic and bill of materials are available for download. After only minutes the Embedded Systems Power Designer provides engineers with circuit schematics and a bill of materials for the converter circuits that fulfill the requirements of the specific FPGA. Design tools like the Embedded Systems Power Designer demonstrate a new paradigm in online engineering solutions that promises to revolutionize the way engineers access information on the Internet. Transim Technology