Enable Pin

Similarly if you toggle the enable pin at a certain rate in many ICs you can get to see current overshoots too. This often depends on allowing the input capacitor to discharge below the UVLO threshold, but not to the point where it hits the internal POR (power on reset) threshold. Because in that case, if you suddenly enable the IC, it has no soft-start anymore, and you will hit max duty cycle, and possibly staircase if the current limit circuitry is not well designed. 

There is no constraints on the enable (clock) line since there are no setup requirements on the clock pin. Consider a two step constraint approach using the set output delay and the set max delay commands. The path from the enable pin of the latch to the primary output can be constrained using the set output delay command. The path to the enable pin of the latch can be constrained using the set max delay command. 

Example 7.1 shows a VHDL and Verilog code template that can be used to infer flops with clock enables. The flops available in CLBs already have a clock enable pin, hence, one can use the code template in Example 7-1 for design scenarios that need gated clocks. The intent is to exploit all the dedicated logic resources available rather than use the limited combinational resources to implement the gated clock logic. 

TC identifies and breaks combinational feedback loops automatically. The selection of the point in the combinational feedback loop chosen is reported in the check test output. Heuristics have been incorporated into check test that determine the point at which combinational feedback loops are broken. Further, TC understands functionally broken loops. The nodes at which check test avoids breaking combinational feedback loops in order of priority are as follows tristate/bidir enable pins, pins directly feeding asynchronous inputs of sequential elements, pins directly feeding other inputs of sequential elements, and gates with a large fan-out. 

TC infers a clock by backtracking from pins which have setup and hold arcs specified. If the reset signal is connected to either enable pins of latches (which might be classified as black boxes), synchronous RAM piits, or any pins which have setup and hold arcs specified in the libraiy, it shall be inferred as a clock by TC. If these cells are already classified as black-boxes, specify a testjsolate attribute on them using the seMest lsolate command. This will prevent the reset line from being inferred as a clock. 

The untested faults are most likely the faults associated with the enabling logic of the bidirectionals. Any fault at the enable pin of the three-state cell will cause a good machine (or faulty machine) value of Z on output of the three-state cell. This will... 

Quick Opening Devices. Breech block, tapered or interrupted thread, or pinned closures are often used when an end cover has to be removed quickly, as with some isostatic presses (126,136), or to enable the end cover to be removed easily after the vessel has been heated to high temperatures. 

For similar human reasons, we should document every single oscilloscope plot carefully the moment we capture it (assuming it seems meaningful of course). Write down the input and output voltages, currents, specific applied conditions (i.e., power-up into short circuit), the state of the other pins, and so on. Don t forget to keep close track of what each channel represented (or later, just watch yourself suffer Hey look, by moving the pole-zero pair apart, I now have negligible overshoot at start-up. Oops, that must have been the Enable... 

The incorporation of an earth pin is not only desirable for safety, it also enables us to know the potential of the other pins, because we cite them with respect to the earth pin. 

Enabled by the high resolution of spectra, which is enhanced by the use of spatial filter assembly having a small (200 pm) pin hole, the principle of the strain-induced band shift in Raman spectra has been further extended to the measurement of residual thermal shrinkage stresses in model composites (Young et al., 1989 Filiou et al., 1992). The strain mapping technique within the fibers is employed to study the... 

Ex situ (also known as spotted or printed) arrays have become very popular formats, especially for the building of custom noncommercial arrays used primarily by academic laboratories [see Association of Biomolecular Resource Facilities (ABRF) surveys on microarrays atwww.abrf.org]. The printed cDNA microarray was largely developed from gene expression work originating in the laboratories of RO. Brown and R.W. Davis at Stanford University (Schena et al., 1995). Plans for the construction of the microarrayer and split pin designs were available at the Brown lab website at http //cmgm.stanford.edu/ pbrown/mguide/index.html. This enabled researchers to prepare their own microarrays appropriate for their particular experiments. 

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