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Relation between input transition, clock transition and set up and hold time of a FF

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biju4u90

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The set up and hold times of a FF are function of clock transition time and input transition times. What is the relation actually?? It seems the setup and hold times increase with high clock transition values. Is it correct? What about the input transition time?

Code:
timing () {
				related_pin : "CLK";
				timing_type : "hold_rising";
				rise_constraint ("hold_template_6x7") {
					index_1("1, 30, 60, 110, 220, 440");
					index_2("1, 40, 80, 165, 330, 660, 1320");
					values("-2.315, -19.627, -36.098, -65.848, -109.046, -172.896, -259.683","5.767, -10.608, -27.015, -55.778, -97.961, -161.904, -249.602","11.97, -5.299, -20.8, -48.6, -90.8, -153.7, -242.4","22.098, 4.8, -11.7, -39.45, -80.65, -141.65, -231.25","37.811, 20.498, 4.077, -22.75, -63.05, -122.95, -211.65","61.583, 44.253, 28.715, 0.95, -38.35, -97.25, -183.05");
				}
				fall_constraint ("hold_template_6x7") {
					index_1("1, 30, 60, 110, 220, 440");
					index_2("1, 40, 80, 165, 330, 660, 1320");
					values("-2.313, -18.656, -34.133, -62.933, -105.133, -151.394, -220.541","11.628, -4.712, -20.257, -50.004, -92.184, -138.445, -206.637","22.72, 8.381, -8.1, -36.9, -78.078, -124.4, -192.53","41.634, 26.23, 10.81, -17.05, -57.238, -102.55, -170.75","75.87, 60.553, 46.05, 18.25, -21.011, -64.35, -133.55","131.848, 116.476, 102, 77.153, 37.85, -10.371, -78.55");
				}
			}
			timing () {
				related_pin : "CLK";
				timing_type : "setup_rising";
				rise_constraint ("setup_template_6x7") {
					index_1("1, 30, 60, 110, 220, 440");
					index_2("1, 40, 80, 165, 330, 660, 1320");
					values("37.313, 54.64, 71.096, 100.846, 144.046, 207.844, 295.533","29.262, 45.569, 62.05, 90.784, 132.991, 196.871, 284.602","22.956, 40.297, 55.799, 83.6, 125.8, 188.7, 277.3","12.889, 30.217, 46.636, 74.45, 115.65, 176.55, 266.263","-2.811, 14.447, 30.918, 57.75, 97.95, 157.95, 246.65","-26.583, -9.273, 6.227, 34.05, 73.25, 132.25, 218.05");
				}
				fall_constraint ("setup_template_6x7") {
					index_1("1, 30, 60, 110, 220, 440");
					index_2("1, 40, 80, 165, 330, 660, 1320");
					values("57.813, 73.155, 89.646, 117.433, 156.633, 208.834, 272.134","44.901, 61.186, 76.699, 105.538, 144.7, 196.881, 259.2","31.78, 47.169, 63.581, 91.4, 131.6, 183.8, 247.1","12.867, 28.236, 43.713, 72.45, 111.75, 164.85, 229.15","-17.47, -2.145, 13.367, 41.15, 80.45, 133.55, 197.773","-60.77, -45.4, -29.9, -3.05, 36.15, 89.3, 154.55");
				}

This is a piece of my .lib file where index 1 represents clock transition time and index 2 represents input transition time. It seems, according to the library, the set up time decreases with increased clock transition times!! Is it so?
 

Too many question and it seems to me that you have not made enough experiments to understand it.
Let put some transition value to the FF/CLK driver and see what happen in timing report.
Let check out the form of the matrix and input factor that vary up and down.
I believe you have tool, lib and design. Why dont you try ?
 

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