Path delay

Zeitoun, A., C. N. Chuah, S. Bhattacharyya, and C. Diot, An AS-level study of Internet path delay characteristics, technical report, 2003, available at http //ipmon.sprint.com/pubs trs/trs/RR03-ATL-051699-AS-delay.pdf... 

Notice that with sharing an ALU, a multiplexer has been introduced at one of the inputs of the ALU that contributes to the path delay. However,... 

Multiphoton absorption cross sections as functions of entanglement times and path delayes reflect quantum correlations among the optical fields constituting an entangled state [93,94]. There may occur entanglement-induced multiphoton transparency—the value of absorption cross section drops to zero for some values of entanglement times and path delayes (see Fig. 22 for entangled three-photon absorption cross section). 

The dependence of multiphoton absorption cross sections on entanglement times and path delayes may, in principle, be used for the determination of spectrum and dipol moments of the absorbing material (for two-photon (three-photon) absorption, see Ref. 95 (Ref. 94). 

According to the analysis presented in the previous section, we realized that the most effective way to reduce critical path delay is to fold the fabric into two stacked chips under the 2.5-D scenario. Therefore, we vertically split the chip into two halves and the resultant two chips can be bonded in a face-to-face manner. The layouts of the two chips in 2.5-D system are shown in Fig. 3.9. Note that the size... 

Lumped Capacitance of inter-chip contact (fF) Bus Wire Delay (ns) Critical Path Delay (ns) Clock Frequency (MHz) Improvement to 2D Solution... 

D placement tools have to be able to optimize multiple cost objectives in addition to the traditional wire length and critical path delay. 

There exists several definitions of the Quality Of Service (QoS) innetwork systems literature. Among of them, there is the path delay between a node and a user-station along a multi-hop route. The number of hops traduces the latency of a network to carry information between these nodes which is a critical indicator in the case of safety application where a decision has to be taken in time. The shorter this number is, the more efficient this network is. Table.2 summarizes useful... 

Autocorrelation, background-free Method of measuring mode-locked laser pulse lengths, in which the pulse train is split into two beams, one of which is delayed, and in which the two beams are focused to overlap in a crystal whose phase-matching conditions permit frequency summing only when one photon is taken from each beam. The summed or doubled power, versus path delay, is proportional to the autocorrelation in time of the pulse with itself and so gives the pulse length, if the functional form of the pulse shape is known. 

Linear Buffered-Path Delay Model. Recall the linear-delay model introduced in Chap. 3. The delay along an optimally buffered interconnect of length I is given by delay(/) = t I, where t is a technology dependent constant. In general, t depends on the buffer library size and the input slew rate. In this chapter, we refer to T = delay(wire)/length(w/re). 

Resynthesize the system to balance to the critical path delay of different combinational clusters. 

Simulation Models. Simulation models are extended versions of functional models.They contain all the functional information as well as detailed information about path delays through a part and rise and faU times. They are used to ensure that worst-case timing conditions result in a properly operating design. 

Let us analyze these timing reports. The report gives the point in the design, which is usually a poit or a pin of a libraiy cell, the incremental delay through the cell (listed in the Incr column), and the Path delay (listed under the Path column) or the delay in the path up to that point. In other words, the path delays are calculated by adding up the incremental delays. 

Once the max delay requirements imposed due to the setup constraints for the sequential cells have been met, DC can be used to fix the minimum path delay requirements. Since the path delays are the maximum in the worst case timing analysis or worst case operating conditions, max delay requirements must be met in the worst case operating conditions. 

The minimum delay requirements are set by the hold constraints for the sequential cells. Hold time problems are caused due to short delay paths between registers which cause the data signal to propagate through two adjacent flip-flops on a single clock edge. Since path delays are the shortest under best-case operating conditions, hold time problems are maximum in these conditions. Hence, hold violations have to be fixed under these conditions. 

Hold time problems will generally occur in shift register structures or scan chains. Since by default DC treats the clock as ideal with no path delays, one must account for the network delay by using the set clock skew -propagated command. 

Major advances in semiconductor technologies have made possible ICs under 0.3 micron technology. As a result of these shrinking geometries, net delay is fast becoming a major component of path delays. Hence, it is essential that synthesis tools take into consideration information provided by tools used downstream in the design flow like floor-planners and place and route tools. This chapter discusses the links from and to DC and backend tools like floorplanners and place and route tools. 

Structural Adjustment Get critical path delay for the current stage by including multiplexer delay. If the critical path delay exceeds the clock cycle, undo sharing for a least expensive multiplexed operation that is on the critical path and go to step 7. Otherwise, go to next step. 

W. Donath et. al Timing Driven Placement Using Complete Path Delays. In Proc. of 27th Design Automation Conference, June 1990. 

In Akkin et al, a polarization-sensitive low coherence fiber interferometer was used to measure -0.5 nm, 1 ms displacements in crayfish leg nerves. Calcite prisms are used to compensate for optical path delay between the nerve reflection and a reference cover glass. The authors suggested that the technology may allow noninvasive detection of various neuropathies. 

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