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.