CAJ | 학술논문

为了准确评估工艺参数偏差对电路延时的影响，该文提出一种考虑空间关联工艺偏差的统计静态时序分析方法。该方法采用一种考虑非高斯分布工艺参数的二阶延时模型，通过引入临时变量，将2维非线性模型降阶为1维线性模型；再通过计算到达时间的紧密度概率、均值、二阶矩、方差及敏感度系数，完成了非线性非高斯延时表达式的求和、求极大值操作。经ISCAS89电路集测试表明，与蒙特卡洛仿真(MC)相比，该方法对应延时分布的均值、标准差、5%延时点及95%延时点的平均相对误差分别为0.81%,-0.72%,2.23%及-0.05%，而运行时间仅为蒙特卡洛仿真的0.21%，证明该方法具有较高的准确度和较快的运行速度。
위료준학평고공예삼수편차대전로연시적영향，해문제출일충고필공간관련공예편차적통계정태시서분석방법。해방법채용일충고필비고사분포공예삼수적이계연시모형，통과인입림시변량，장2유비선성모형강계위1유선성모형；재통과계산도체시간적긴밀도개솔、균치、이계구、방차급민감도계수，완성료비선성비고사연시표체식적구화、구겁대치조작。경ISCAS89전로집측시표명，여몽특잡락방진(MC)상비，해방법대응연시분포적균치、표준차、5%연시점급95%연시점적평균상대오차분별위0.81%,-0.72%,2.23%급-0.05%，이운행시간부위몽특잡락방진적0.21%，증명해방법구유교고적준학도화교쾌적운행속도。
To evaluate effects of process variations on circuit delay accurately, this study proposes a Statistical Static Timing Analysis (SSTA) which incorporates process variations with spatial correlations. The algorithm applies a second order delay model that taking into account the non-Gaussian parameters - by inducting the notion of ‘conditional variables’, the 2D non-linear delay model is translated into 1D linear one; and by computing the tightness probability, mean, variance, second-order moment and sensitivity coefficients of the circuit arrival time, the sum and max operations of non-linear and non-Gaussian delay expressions are implemented. For the ISCAS89 benchmark circuits, as compared to Monte Carlo (MC) simulation, the average errors of 0.81%,-0.72%, 2.23% and-0.05%, in the mean, variance, 5% and 95% quantile points of the circuit delay are obtained respectively for the proposed method. The runtime of the proposed method is about 0.21% of the value of Monte Carlo simulation. The experimental results prove that the high accuracy of the SSTA is reliable.