Philips Semiconductors
Product specification
Dual D-type flip-flop with set and reset;
positive-edge trigger
FEATURES
•
Wide supply voltage range from 2.0 to 6.0 V
•
Symmetrical output impedance
•
High noise immunity
•
Low power dissipation
•
Balanced propagation delays
•
ESD protection:
HBM EIA/JESD22-A114-A exceeds 2000 V
MM EIA/JESD22-A115-A exceeds 200 V.
74HC74; 74HCT74
GENERAL DESCRIPTION
The 74HC/HCT74 is a high-speed Si-gate CMOS device
and is pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
The 74HC/HCT74 are dual positive-edge triggered, D-type
flip-flops with individual data (D) inputs, clock (CP) inputs,
set (SD) and reset (RD) inputs; also complementary
Q and Q outputs.
The set and reset are asynchronous active LOW inputs
and operate independently of the clock input. Information
on the data input is transferred to the Q output on the
LOW-to-HIGH transition of the clock pulse. The D inputs
must be stable one set-up time prior to the LOW-to-HIGH
clock transition for predictable operation.
Schmitt-trigger action in the clock input makes the circuit
highly tolerant to slower clock rise and fall times.
QUICK REFERENCE DATA
GND = 0 V; T
amb
= 25
°C;
t
r
= t
f
= 6 ns
TYPICAL
SYMBOL
t
PHL
/t
PLH
PARAMETER
propagation delay
nCP to nQ, nQ
nSD to nQ, nQ
nRD to nQ, nQ
f
max
C
I
C
PD
Notes
1. C
PD
is used to determine the dynamic power dissipation (P
D
in
µW).
P
D
= C
PD
×
V
CC2
×
f
i
×
N +
Σ(C
L
×
V
CC2
×
f
o
) where:
f
i
= input frequency in MHz;
f
o
= output frequency in MHz;
C
L
= output load capacitance in pF;
V
CC
= supply voltage in Volts;
N = total load switching outputs;
Σ(C
L
×
V
CC2
×
f
o
) = sum of the outputs.
2. For 74HC74 the condition is V
I
= GND to V
CC
.
For 74HCT74 the condition is V
I
= GND to V
CC
−
1.5 V.
maximum clock frequency
input capacitance
power dissipation capacitance per flip-flop
notes 1 and 2
CONDITIONS
HC
C
L
= 15 pF; V
CC
= 5 V
14
15
16
76
3.5
24
15
18
18
59
3.5
29
ns
ns
ns
MHz
pF
pF
HCT
UNIT
2003 Jul 10
2
PHILIPS [ NXP SEMICONDUCTORS ]
