The name is absent

path. We can measure the time difference between the transitions in line a and
in line n. Let us denote the total delay of the path Pi for the rising transition by
⅛(Fι)∙ ₄

,o The total path delay is an additive composition of the delays of its elements.
For example, delay of the path P₁ can be written as the summation of the delays
in line a, gate g₁, line k, line e, gate g⅛, and so on. i.e.,

d_r(Pι) — d(α) ÷ d_r(<7ι) ÷ d(z) ÷ d(e ) ÷ df(g3)

+ d(J ) + ⅛¼) + d(s ) + d_f(g₆) + d(k )

+ d_r(g₇) + d(n ),                                  (4.2)

where d{x) is the delay of the line x, and d_r(g_i) and df(g_i) are the rising and
falling delays of gate g⅛, respectively.

Here, we assume for presentation clarity that interconnect delays (line delays)
are zero. The proposed method can be easily extended to cases with non-zero
interconnect delays. Note that it maybe the case that variations in the inter-
connects have a separate statistical representation. In such scenarios, one may
consider compressed sensing methods that address the summation of two distinct
distributions in one framework [24]. Assuming zero interconnect delays, Equation
4.2 reduces to:

d_r(Pι) = ⅛∙(<7ι) ÷ df{gs) + d_r(g⅛) + df(gβ) + d_r(g₇).          (4.3)

In Section 4.1, we illustrated that because of the process variation, delays of

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