7474中文資料仙童半導(dǎo)體數(shù)據(jù)手冊(cè)PDF規(guī)格書

General Description

This device contains two independent positive-edge-triggered D-type flip-flops with complementary outputs. The information on the D input is accepted by the flip-flops on the positive going edge of the clock pulse. The triggering occurs at a voltage level and is not directly related to the transition time of the rising edge of the clock. The data on the D input may be changed while the clock is LOW or HIGH without affecting the outputs as long as the data setup and hold times are not violated. A LOW logic level on the preset or clear inputs will set or reset the outputs regardless of the logic levels of the other inputs.