TECHNICAL DATA
79
Dual D Flip-Flop with Set and Rese t
High-Perform ance Silicon-Gate C MOS
The IN74HC74A is identical in pinout to the LS/ALS74. The
device inputs are compatible with standard CMOS outputs; with pullup
resistors, they are compatible with LS/ALSTTL outputs.
This device consists of two D flip-flops with individual Set, Reset,
and Clock inputs. Information at a D-input is transferred to the
corresponding Q output on the next positive going edge of the clock
input. Both Q and Q outputs are available from each flip-flop. The Set
and Reset inputs are asynchronous.
• Outputs Directly Interface to CMOS, NMOS, and TTL
• Operating Voltage Range: 2.0 to 6.0 V
• Low Input Current: 1.0 µA
• High Noise Immunity Characteristic of CMOS Devices
IN74HC74A
ORDERING INFORMATION
IN74HC74AN Plastic
IN74HC74AD SOIC
TA = -55° to 125° C for all packages
LOGIC DIAGRAM
PIN 14 =VCC
PIN 7 = GND
PIN ASSIGNMENT
FUNCTION TABLE
Inputs Outputs
Set Reset Clock Data Q Q
LH X XHL
HL X XLH
LL X XH
*H*
HH HHL
HH LLH
H H L X No Cha nge
H H H X No Change
H H X No Change
*Both outputs will remain high as long as Set
and Reset are low, but the output states are
unpre dictable if Set a nd Reset go hi gh
simultaneously.
X = don’t care
IN74HC74A
80
MAXIMUM RATINGS*
Symbol Parameter Value Unit
VCC DC Supply Voltage (Referenced to GND) -0.5 to +7.0 V
VIN DC Input Voltage (Referenced to GND) -1.5 to VCC +1.5 V
VOUT DC Output Voltage (Referenced to GND) -0.5 to VCC +0.5 V
IIN DC Input Current, per Pin ±20 mA
IOUT DC Output Current, per Pin ±25 mA
ICC DC Supply Current, VCC and GND Pins ±50 mA
PDPower Dissipation in Still Air, Plastic DIP+
SOIC Package+ 750
500 mW
Tstg Storage Temperature -65 to +150 °C
TLLead Temperature, 1 mm from Case for 10 Seconds
(Plastic DIP or SOIC Package) 260 °C
*Maximum Ratings are those values beyond which damage to the device may occur.
Functional operation should be restricted to the Recommended Operating Conditions.
+Derating - Plastic DIP: - 10 mW/°C from 65° to 125°C
SOIC Package: : - 7 mW/°C from 65° to 125°C
RECOMMENDED OPERATING CONDITIONS
Symbol Parameter Min Max Unit
VCC DC Supply Voltage (Referenced to GND) 2.0 6.0 V
VIN, VOUT DC Input Voltage, Output Voltage (Referenced to GND) 0 VCC V
TAOperating Temperature, All Package Types -55 +125 °C
tr, tfInput Rise and Fall Time (Figure 1) VCC =2.0 V
VCC =4.5 V
VCC =6.0 V
0
0
0
1000
500
400
ns
Thi s device contains p rote ction c ircuitr y to guard a gainst damage due to hi gh static voltage s or electr ic
fields. However, precautions must be taken to avoid applications of any voltage higher than maximum rated
voltages to this high-impedance circuit. For proper operation, VIN and VOUT should be constrained to the range
GND≤(VIN or VOUT)≤VCC.
Unused inputs must always be tied to an appropriate logic voltage level (e.g., either GND or VCC).
Unused outputs must be left open.
IN74HC74A
81
DC ELECTRICAL CHARACTERISTICS(Voltages Referenced to GND)
VCC Guaranteed Limit
Symbol Parameter Test Conditions V 25 °C
to
-55°C
≤85
°C≤125
°CUnit
VIH Minimum High-Level
Input Voltage VOUT=0.1 V or VCC-0.1 V
IOUT≤ 20 µA2.0
4.5
6.0
1.5
3.15
4.2
1.5
3.15
4.2
1.5
3.15
4.2
V
VIL Maximum Low -
Level Input Voltage VOUT=0.1 V or VCC-0.1 V
IOUT ≤ 20 µA2.0
4.5
6.0
0.5
1.35
1.8
0.5
1.35
1.8
0.5
1.35
1.8
V
VOH Minimum High-Level
Output Voltage VIN=VIH or VIL
IOUT ≤ 20 µA2.0
4.5
6.0
1.9
4.4
5.9
1.9
4.4
5.9
1.9
4.4
5.9
V
VIN=VIH or VIL
IOUT ≤ 4.0 mA
IOUT ≤ 5.2 mA 4.5
6.0 3.98
5.48 3.84
5.34 3.7
5.2
VOL Maximum Low-Level
Output Voltage VIN=VIH or VIL
IOUT ≤ 20 µA2.0
4.5
6.0
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
V
VIN=VIH or VIL
IOUT ≤ 4.0 mA
IOUT ≤ 5.2 mA 4.5
6.0 0.26
0.26 0.33
0.33 0.4
0.4
IIN Maximum Input
Leakage Current VIN=VCC or GND 6.0 ±0.1 ±1.0 ±1.0 µA
ICC Maximum Quiescent
Supply Current
(per Package)
VIN=VCC or GND
IOUT=0µA6.0 2.0 20 80 µA
IN74HC74A
82
AC ELECTRICAL CHARACTERISTICS(CL=50pF,Input tr=tf=6.0 ns)
VCC Guaranteed Limit
Symbol Parameter V 25 °C
to
-55°C
≤85°C≤125°CUnit
fmax Maximum Clock Fr equency (50% Duty Cycle)
(Figures 1 and 4) 2.0
4.5
6.0
6.0
30
35
4.8
24
28
4.0
20
24
MHz
tPLH, tPHL Maximum Prop agatio n Delay, Clo ck to Q or Q
(Figures 1 and 4) 2.0
4.5
6.0
100
20
17
125
25
21
150
30
26
ns
tPLH, tPHL Maximum Propagation Delay, Set or Reset to Q
or Q (Figures 2 and 4) 2.0
4.5
6.0
105
21
18
130
26
22
160
32
27
ns
tTLH, tTHL Maximum Output Transition Time, Any Output
(Figures 1 and 4) 2.0
4.5
6.0
75
15
13
95
19
16
110
22
19
ns
CIN Maximum Input Capacitance - 10 10 10 pF
Power Dissipation Capacitance (Per Flip-Flop) Typical @25°C,VCC=5.0 V
CPD Used to determine the no-load dynamic power
consumption:
PD=CPDVCC2f+ICCVCC
39 pF
TIMING REQUIREMENTS(CL=50pF,Input tr=tf=6.0 ns)
VCC Guaranteed Limit
Symbol Parameter V 25 °C to-55°C≤85°C≤125°CUnit
tsu Minimum S et up Time, Data to Clock
(Figure 3) 2.0
4.5
6.0
80
16
14
100
20
17
120
24
20
ns
thMinimum Hold Time, C lock to Data
(Figure 3) 2.0
4.5
6.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
ns
trec Minimum Recovery Time, Set or
Reset Inactive to Clock (Figure 2) 2.0
4.5
6.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
ns
twMinimum Pulse Width, Clock ( Figure
1) 2.0
4.5
6.0
60
12
10
75
15
13
90
18
15
ns
twMinimum Pulse W idth, S et or Reset
(Figure 2) 2.0
4.5
6.0
60
12
10
75
15
13
90
18
15
ns
tr, tfMaximum Input Ri se and F al l Times
(Figure 1) 2.0
4.5
6.0
1000
500
400
1000
500
400
1000
500
400
ns
IN74HC74A
83
Figure 1. Switching Waveform Figure 2. Switching Waveform
Figure 3. Switching Waveform Figure 4.Test Circuit
EXPANDED LOGIC DIAGRAM
