
© 2005 Fairchild Semiconductor Corporation DS005106 www.fairchildsemi.com
September 1983
Revised January 2005
MM74HC74A Dual D-Type Flip-Flop wit h Preset and Clear
MM74HC74A
Dual D-Type Flip-Fl op wit h Preset and Clear
General Description
The MM74HC74A utilizes advanced silicon-gate CMOS
technology to achieve operating speeds similar to the
equivalen t LS-T TL par t. It possesse s the high no ise imm u-
nity and low power consumption of standard CMOS inte-
grated circuits, along with the ability to drive 10 LS-TTL
loads.
This flip-flop has independent data, preset, clear, and clock
inputs and Q and Q outputs. The logic level present at the
data input is transferred to the output during the positive-
going transition of the clock pulse. Preset and clear are
indepen dent of the clock a nd accomplished b y a low level
at the appropriate input.
The 74HC logic family is functionally and pinout compatible
with the standard 74LS logic family . All inputs are protected
from damage due to static discharge by internal diode
clamps to VCC and ground.
Features
■Typical propagation delay: 20 ns
■Wide power supply range: 2–6V
■Low quiescent current: 40 µA maximum ( 74HC S erie s)
■Low input current: 1 µA maximum
■Fanout of 10 LS-TTL loads
Ordering Code:
Devices also available in Tape and R eel. Speci fy by append ing the suffix let t er “X” to the ordering code.
Pb-F ree packag e per JEDE C J- ST D -020 B.
Connection Diagram
Pin Assignments for DIP, SOIC, SOP and TSSOP
Truth Table
Note: Q0 = the level of Q before the indicated input conditions were estab-
lished.
Note 1: This configuration is nonstable; that is, it will not persist when pre-
set and clear inputs return to their inactive (HIGH) level.
Order Number Package Package Description
Number
MM74HC74AM M14A 14-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150" Narrow
MM74HC74AMX_NL M14A Pb-Free 14-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150" Narrow
MM74HC74ASJ M14D Pb-Free 14-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
MM74HC74AMTC MTC14 14-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
MM74HC74AMTCX_NL MTC14 Pb-Free 14-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm
Wide
MM74HC74AN N14A 14-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300" Wide
Inputs Outputs
PR CLR CLK D Q Q
LHXX H L
HL XX L H
L L X X H (Note 1) H (Note 1)
HH ↑HH L
HH ↑LL H
HH LX Q0 Q
0