Delay Time Characteristics

For VDA-xx15 devices, the accuracy of delay time increments is specified as either ±0.5ns or ±5%, whichever is greater. An illustrative sequence of values would be as follows: 1.0ns±0.5ns, 2.0ns±0.5ns... 10.0ns±0.5ns (=±5%), 11.0ns±5%... 15.0ns±5%. There are a total of 31 incremental steps, but the guaranteed delay times are derived from 15 output values comprising two incremental steps each. Typically, the specified delay outputs are derived from even-numbered steps (step 0, 2, 4, etc). However, delay time accuracy is guaranteed on the basis of pairs of odd-numbered steps in combination. The variation in delay time corresponding to each step is illustrated in the diagram to the right. The black dots in the diagram represent the stable contact points for the selector mechanism, and define each respective step. The dotted lines indicate the delay time selected when moving between steps. The delay time of the even-numbered steps is selected when the selector knob is moved. Even-numbered steps correspond to the tap outputs of earlier tapped-style delay lines, and the odd-numbered steps are supplementary steps achieved through ELMEC's proprietary variability mechanism. Odd numbered steps are interspersed between even-numbered steps at a ratio of approximately 2:8. Printable Version - High Resolution PDF