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SN54F74, SN74F74 DUAL POSITIVE-EDGE-TRIGGERED D-TYPE FLIP-FLOPS
WITH CLEAR AND PRESET
SDFS046A – MARCH 1987 – REVISED OCTOBER 1993
• Package Options Include Plastic
Small-Outline Packages, Ceramic Chip Carriers, and Standard Plastic and Ceramic 300-mil DIPs
description
These devices contain two independent positiveedge-triggered D-type flip-flops. A low level at the preset (PRE) or clear (CLR) inputs sets or resets the outputs regardless of the levels of the other inputs. When PRE and CLR are inactive (high), data at the data (D) input meeting the setup time requirements is transferred to the outputs on the positive-going edge of the clock pulse. Clock triggering occurs at a voltage level and is not directly related to the rise time of the clock pulse.