7474

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The 7474 (variants 74LS74, 74HC74) is a 74-series logic IC with two independent D flip-flops.[1]

Pinout

         .--\/--.
/1RST -> |01  14| -- +5V
   1D -> |02  13| <- /2RST
 1CLK -> |03  12| <- 2D
/1SET -> |04  11| <- 2CLK
   1Q <- |05  10| <- /2SET
  /1Q <- |06  09| -> 2Q
  Gnd -- |07  08| -> /2Q
         `------'

Signal descriptions

For each flip-flop:

Inputs Outputs
/RST /SET CLK D Q /Q
L H X L H
H L H L
L N
H L X U
H H L
L L H

L = low, H = high, ↑ = low to high, X = don't care, N = nonstable, U = unchanged.

References