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MM54HC42/MM74HC42
BCD-to-Decimal Decoder
General Description
This decoder utilizes advanced silicon-gate CMOS technology. Data on the four input pins select one of the 10 outputs
corresponding to the value of the BCD number on the inputs. An output will go low when selected, otherwise it remains high. If the input data is not a valid BCD number all
outputs will remain high. The circuit has high noise immunity
and low power consumption usually associated with CMOS
circuitry, yet also has speeds comparable to low power
Schottky TTL (LS-TTL) circuits, and is capable of driving 10
LS-TTL equivalent loads.
January 1988
All inputs are protected from damage due to static discharge by diodes to V
and ground.
CC
Features
Y
Typical propagation delay: 15 ns
Y
Wide supply range: 2V –6V
Y
Low quiescent current: 80 mA (74HC)
Y
Fanout of 10 LS-TTL loads
MM54HC42/MM74HC42 BCD-to-Decimal Decoder
Connection Diagram
Dual-in-line Package
Top View
Order Number MM54HC42 or MM74HC42
Logic Diagram
TL/F/5301– 1
Truth Table
No.
INVALID
HeHigh Level, LeLow Level
Inputs Outputs
DCBA0123456789
0 LLLLLHHHHHHHHH
1 L L LHHLHHHHHHHH
2 L LHLHHLHHHHHHH
3 LLHHHHHLHHHHHH
4 LHLLHHHHLHHHHH
5 LHLHHHHHHLHHHH
6 LHHLHHHHHHLHHH
7 LHHHHHHHHHHLHH
8 H L L LHHHHHHHHLH
9 H L LHHHHHHHHHHL
HLHLHHHHHHHHHH
HL HHHHHHHHHHHH
HHL LHHHHHHHHHH
HHL HHHHHHHHHHH
HHHL HHHHHHHHHH
HHHHHHHHHHHHHH
TL/F/5301– 2
C
1995 National Semiconductor Corporation RRD-B30M105/Printed in U. S. A.
TL/F/5301
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Absolute Maximum Ratings (Notes1&2)
Operating Conditions
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.
Supply Voltage (V
CC
)
DC Input Voltage (VIN)
DC Output Voltage (V
OUT
)
Clamp Diode Current (IIK,IOK)
DC Output Current, per pin (I
OUT
)
DC VCCor GND Current, per pin (ICC)
Storage Temperature Range (T
STG
b
b
)
b
0.5 toa7.0V
1.5 to V
CC
0.5 to V
CC
g
g
b
g
65§Ctoa150§C
a
1.5V
a
0.5V
20 mA
25 mA
50 mA
Power Dissipation (PD)
(Note 3) 600 mW
Supply Voltage (V
)26V
CC
DC Input or Output Voltage 0 V
(V
IN,VOUT
)
Operating Temp. Range (T
MM74HC
MM54HC
Input Rise or Fall Times
e
2.0V(tr,tf) 1000 ns
V
CC
e
V
4.5V 500 ns
CC
e
V
6.0V 400 ns
CC
S.O. Package only 500 mW
Lead Temp. (T
) (Soldering 10 seconds) 260§C
L
DC Electrical Characteristics (Note 4)
Symbol Parameter Conditions V
CC
A
e
T
25§C
Typ Guaranteed Limits
V
IH
Minimum High Level 2.0V 1.5 1.5 1.5 V
Input Voltage 4.5V 3.15 3.15 3.15 V
6.0V 4.2 4.2 4.2 V
V
IL
Maximum Low Level 2.0V 0.5 0.5 0.5 V
Input Voltage** 4.5V 1.35 1.35 1.35 V
6.0V 1.8 1.8 1.8 V
V
OH
Minimum High Level V
Output Voltage
e
VIHor V
l
IN
I
OUT
IL
s
20 mA 2.0V 2.0 1.9 1.9 1.9 V
l
4.5V 4.5 4.4 4.4 4.4 V
6.0V 6.0 5.9 5.9 5.9 V
e
V
VIHor V
IN
I
l
OUT
I
l
OUT
l
IN
I
OUT
e
V
OL
Minimum Low Level V
Output Voltage
IL
s
4.0 mA 4.5V 4.2 3.98 3.84 3.7 V
l
s
5.2 mA 6.0V 5.7 5.48 5.34 5.2 V
l
VIHor V
IL
s
20 mA 2.0V 0 0.1 0.1 0.1 V
l
4.5V 0 0.1 0.1 0.1 V
6.0V 0 0.1 0.1 0.1 V
e
V
VIHor V
IN
I
l
OUT
I
l
OUT
I
IN
I
CC
Note 1: Absolute Maximum Ratings are those values beyond which damage to the device may occur.
Note 2: Unless otherwise specified all voltages are referenced to ground.
Note 3: Power Dissipation temperature derating Ð plastic ‘‘N’’ package:
Note 4: For a power supply of 5V
designing with this supply. Worst case V
I
**V
Maximum Input V
Current
Maximum Quiescent V
Supply Current I
, and IOZ) occur for CMOS at the higher voltage and so the 6.0V values should be used.
CC
limits are currently tested at 20% of VCC. The above VILspecification (30% of VCC) will be implemented no later than Q1, CY’89.
IL
e
IN
e
IN
OUT
g
10% the worst case output voltages (VOH, and VOL) occur for HC at 4.5V. Thus the 4.5V values should be used when
and VILoccur at V
IH
IL
s
4.0 mA 4.5V 0.2 0.26 0.33 0.4 V
l
s
5.2 mA 6.0V 0.2 0.26 0.33 0.4 V
l
VCCor GND 6.0V
g
0.1
VCCor GND 6.0V 8.0 80 160 mA
e
0 mA
b
12 mW/§C from 65§Cto85§C; ceramic ‘‘J’’ package:b12 mW/§C from 100§Cto125§C.
e
5.5V and 4.5V respectively. (The VIHvalue at 5.5V is 3.85V.) The worst case leakage current (IIN,
CC
74HC 54HC
eb
T
40 to 85§CT
A
g
1.0
Min Max Units
)
A
b
b
40
55
eb
A
55 to 125§C
g
a
a
1.0 mA
CC
85
125
V
C
§
C
§
Units
2