Datasheet
SN54HC74, SN74HC74
DUAL D-TYPE POSITIVE-EDGE-TRIGGERED FLIP-FLOPS
WITH CLEAR AND PRESET
SCLS094D – DECEMBER 1982 – REVISED JULY 2003
5
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
PARAMETER MEASUREMENT INFORMATION
VOLTAGE WAVEFORMS
SETUP AND HOLD AND INPUT RISE AND FALL TIMES
VOLTAGE WAVEFORMS
PULSE DURATIONS
t
h
t
su
50%
50%50%
10%10%
90% 90%
V
CC
V
CC
0 V
0 V
t
r
t
f
Reference
Input
Data
Input
50%
High-Level
Pulse
50%
V
CC
0 V
50%
50%
V
CC
0 V
t
w
Low-Level
Pulse
VOLTAGE WAVEFORMS
PROPAGATION DELAY AND OUTPUT TRANSITION TIMES
50%
50%50%
10%10%
90% 90%
V
CC
V
OH
V
OL
0 V
t
r
t
f
Input
In-Phase
Output
50%
t
PLH
t
PHL
50% 50%
10% 10%
90%90%
V
OH
V
OL
t
r
t
f
t
PHL
t
PLH
Out-of-Phase
Output
Test
Point
From Output
Under Test
C
L
= 50 pF
(see Note A)
LOAD CIRCUIT
NOTES: A. C
L
includes probe and test-fixture capacitance.
B. Phase relationships between waveforms were chosen arbitrarily. All input pulses are supplied by generators having the following
characteristics: PRR ≤ 1 MHz, Z
O
= 50 Ω, t
r
= 6 ns, t
f
= 6 ns.
C. For clock inputs, f
max
is measured when the input duty cycle is 50%.
D. The outputs are measured one at a time with one input transition per measurement.
E. t
PLH
and t
PHL
are the same as t
pd
.
Figure 1. Load Circuit and Voltage Waveforms