Pattern-Directed Circuit VirtualPartitioning for Test PowerReductionDianwei Hu and Dong XiangQiang XuTsinghuaUniversityTheChineseUniversityofBeijing,ChinaHong KongTG清华大学Tsinghua University
Pattern-Directed Circuit Virtual Partitioning for Test Power Reduction Qiang Xu The Chinese University of Hong Kong Dianwei Hu and Dong Xiang Tsinghua University Beijing, China
Outline■BackgroundPattern-Directed Virtual PartitioningRouting-Aware Virtual Partitioning■ExperimentalResults■Conclusion
Outline ◼Background ◼Pattern-Directed Virtual Partitioning ◼Routing-Aware Virtual Partitioning ◼Experimental Results ◼Conclusion
TestPowerTogglerate intest mode may be significantlyhigherthan that in functional modeExcessiveaccumulatedpower->permanentdamageExcessiveinstantaneouspower->testyieldlossExcessive test power is a major concern!
Test Power ◼ Toggle rate in test mode may be significantly higher than that in functional mode ◆Excessive accumulated power -> permanent damage ◆Excessive instantaneous power -> test yield loss Excessive test power is a major concern!
PriorWork onTestPowerReductionScan chainmanipulationScan chainpartitioning (e.g.,Whetsel ITCo2)Scan chain reordering (e.g., Bonhomme ITC'02)TestvectormanipulationPower-awareATPG (e.g.,Wang TCAD'98)Low-powerX-filling(e.g.,ButlerITC'04,WenITC'05)Test vector reordering(e.g.,DabholkarTCAD'98Test schedulingCircuitmodification
Prior Work on Test Power Reduction ◼ Scan chain manipulation: ◆ Scan chain partitioning (e.g., Whetsel ITC’02) ◆ Scan chain reordering (e.g., Bonhomme ITC’02) ◼ Test vector manipulation: ◆ Power-aware ATPG (e.g., Wang TCAD’98) ◆ Low-power X-filling (e.g., Butler ITC’04, Wen ITC’05) ◆ Test vector reordering (e.g., Dabholkar TCAD’98) ◼ Test scheduling ◼ Circuit modification
Circuit Partitioning for Test Power ReductionCircuitunderTestwrapperScan chainDataScan chainScanchainPTesterGlue LogicwrapperScan chainScanchainSETCKP2
Circuit Partitioning for Test Power Reduction Tester Data SE TCK Glue Logic Circuit under Test wrapper Scan chain Scan chain Scan chain P1 wrapper Scan chain Scan chain P2