Altera power analyzer aims at FPGAs

Power analysis is no longer just for ASIC designers. FPGAs based on 90nm technology also have dynamic and leakage power issues, and altera Corp. recently addressed these issues by adding a power analysis capability to its quartus II design software.

Quartus II ver 4.2 introduces the PowerPlay technology suite, which includes what Altera calls the industry's most advanced tools for programmable logic power analysis and optimization. Included are a spreadsheet that gives early power consumption estimates and an analyzer that yields more detailed and accurate estimations after placement and routing. Altera intends to add automated optimization software to Quartus II in the first half of 2005.

The driver behind the new software is Altera's high-end 90nm FPGAs, including the Stratix II and Cyclone II devices, said Chris Balough, director of software and tool marketing at Altera. A large and growing market for these devices is consumer electronics, where concerns about power consumption run high, he said.

Like 90nm ASICs, 90nm FPGAs exhibit both leakage and dynamic power. "We do a lot to manage leakage when we design the device ourselves," said Balough. "We design transistors, so we pay for high performance with a little bit of leakage." There's not much the end user can do about leakage current, Balough said, though the new analysis tools can at least show what the power loss will be. But the user has more control over dynamic and I/O power, and the PowerPlay tools analyze that as well.

The suite starts with the Early Power Estimator spreadsheet, available online free and not built into Quartus II. Users input such data as number of registers, transition rates, clocks and frequency, I/O and memory, temperature, airflow and heat sinking.

The spreadsheet's power reports can help users make critical architectural decisions, such as which parts of a design to put in an FPGA and what functionality belongs there, Balough said. "You can decide if you really want to run that clock at 300MHz or if you really need that functionality."

Phil Simpson, Altera's senior manager for software product planning, noted that the accuracy of the spreadsheet depends on the information the user puts into it. Typically, he said, its reports are within 20 to 35 percent of the actual power numbers.

Once an architecture is chosen and an FPGA is placed and routed, users can turn to the PowerPlay Analyzer tool, which is built into Quartus II 4.2. With added input-simulation results, placement and routing results and node activity, the analyzer can return more accurate reports than the spreadsheet.

Quartus II ver 4.2 is now available.

- Richard Goering

EE Times