3.3 V ECL Programmable Delay Chip

The MC100EP195B is a Programmable Delay Chip (PDC) designed primarily for clock deskewing and timing adjustment. It provides variable delay of a differential NECL/PECL input transition. The delay section consists of a programmable matrix of gates and multiplexers as shown in the logic diagram, Figure 2. The delay increment of the EP195B has a digitally selectable resolution of about 10 ps and a net range of up to 10.2 ns. The required delay is selected by the 10 data select inputs D(9:0) values and controlled by the LEN (pin 10). A LOW level on LEN allows a transparent LOAD mode of real time delay values by D(9:0). A LOW to HIGH transition on LEN will LOCK and HOLD current values present against any subsequent changes in D(10:0). The approximate delay values for varying tap numbers correlating to D0 (LSB) through D9 (MSB) are shown in Table 6 and Figure 3.