October 1987
Revised January 1999
MM74C48 BCD
-
t
o-
7 Segm
ent
D
e
coder
© 1999 Fairchild Semiconductor Corporation
DS005883.prf
www.fairchildsemi.com
MM74C48
BCD-to-7 Segment Decoder
General Description
The MM74C48 BCD-to-7 segment decoder is a monolithic
complementary MOS (CMOS) integrated circuit con-
structed with N- and P-channel enhancement transistors.
Seven NAND gates and one driver are connected in pairs
to make binary-coded decimal (BCD) data and its comple-
ment available to the seven decoding AND-OR-INVERT
gates. The remaining NAND gate and three input buffers
provide test-blanking input/ripple-blanking output, and rip-
ple-blanking inputs.
Features
s
Wide supply voltage range:
3.0V to 15V
s
Guaranteed noise margin:
1.0V
s
High noise immunity:
0.45 V
CC
(typ.)
s
Low power TTL compatibility:
fan out of 2 driving 74L
s
High current sourcing output (up to 50 mA)
s
Ripple blanking for leading or trailing zeros (optional)
s
Lamp test provision
Ordering Code:
Connection Diagrams
Pin Assignments for DIP
Top View
Segment Identification
Numerical Designations
and Resultant Displays
Order Number
Package Number
Package Description
MM74C48N
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300" Wide
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2
MM
74C48
Truth Table
H
=
HIGH Level
L
=
LOW Level
X
=
Irrelevant
Note 1: One BI/RBO is wire-AND logic serving as blanking input (BI) and/or ripple-blanking output (RBO).
Note 2: The blanking input (BI) must be open when output functions 015 are desired. The ripple-blanking input (RBI) must be HIGH, if blanking of a decimal
zero is not desired.
Note 3: When a LOW logic level is applied directly to the blanking input (BI), all segment outputs are LOW regardless of the level of any other input.
Note 4: When ripple-blanking input (RBI) and inputs A, B, C, and D are at a LOW level with the lamp-test input HIGH, all segment outputs go LOW and the
ripple-blanking output (RBO) goes to a LOW level (response condition).
Note 5: When the blanking input/ripple-blanking output (BI/RBO) is open and a LOW is applied to the lamp-test input, all segment outputs are HIGH.
Decimal
Inputs
Outputs
or
BI/RBO Note
Function
LT
RBI
D
C
B
A
(Note 1)
a
b
c
d
e
f
g
0
H
H
L
L
L
L
H
H
H
H
H
H
H
L
(Note 2)
1
H
X
L
L
L
H
H
L
H
H
L
L
L
L
(Note 2)
2
H
X
L
L
H
L
H
H
H
L
H
H
L
H
3
H
X
L
L
H
H
H
H
H
H
H
L
L
H
4
H
X
L
H
L
L
H
L
H
H
L
L
H
H
5
H
X
L
H
L
H
H
H
L
H
H
L
H
H
6
H
X
L
H
H
L
H
L
L
H
H
H
H
H
7
H
X
L
H
H
H
H
H
H
H
L
L
L
L
8
H
X
H
L
L
L
H
H
H
H
H
H
H
H
9
H
X
H
L
L
H
H
H
H
H
L
L
H
H
10
H
X
H
L
H
L
H
L
L
L
H
H
L
H
11
H
X
H
L
H
H
H
L
L
H
H
L
L
H
12
H
X
H
H
L
L
H
L
H
L
L
L
H
H
13
H
X
H
H
L
H
H
H
L
L
H
L
H
H
14
H
X
H
H
H
L
H
L
L
L
H
H
H
H
15
H
X
H
H
H
H
H
L
L
L
L
L
L
L
BI
X
X
X
X
X
X
L
L
L
L
L
L
L
L
(Note 3)
RBI
H
L
L
L
L
L
L
L
L
L
L
L
L
L
(Note 4)
LT
L
X
X
X
X
X
H
H
H
H
H
H
H
H
(Note 5)
3
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MM74C48
Absolute Maximum Ratings
(Note 6)
Note 6: "Absolute Maximum Ratings" are those values beyond which the
safety of the device cannot be guaranteed. Except for "Operating Tempera-
ture Range" they are not meant to imply that the devices should be oper-
ated at these limits. The Electrical Characteristics table provides conditions
for actual device operation.
DC Electrical Characteristics
Voltage at Any Pin
-
0.3V to V
CC
+
0.3V
Operating Temperature Range
-
40
°
C to
+
85
°
C
Storage Temperature Range
-
65
°
C to
+
150
°
C
Power Dissipation
Dual-In-Line
700 mW
Small Outline
500 mW
Operating V
CC
Range
3.0V to 15V
Absolute Maximum V
CC
18V
Lead Temperature
(Soldering, 10 seconds)
260
°
C
Symbol
Parameter
Conditions
Min
Typ
Max
Units
CMOS to CMOS
V
IN(1)
Logical "1" Input Voltage
V
CC
=
5.0V
3.5
V
V
CC
=
10V
8.0
V
V
IN(0)
Logical "0" Input Voltage
V
CC
=
5.0V
1.5
V
V
CC
=
10V
2.0
V
V
OUT(1)
Logical "1" Output Voltage
V
CC
=
5.0V, I
O
=
-
10
µ
A
4.5
V
(RB Output Only)
V
CC
=
10V, I
O
=
-
10
µ
A
9.0
V
V
OUT(0)
Logical "0" Output Voltage
V
CC
=
5.0V, I
O
=
10
µ
A
0.5
V
V
CC
=
10V, I
O
=
10
µ
A
1.0
V
I
IN(1)
Logical "1" Input Current
V
CC
=
15.0V, V
IN
=
15V
0.005
1.0
µ
A
I
IN(0)
Logical "0" Input Current
V
CC
=
15.0V, V
IN
=
0V
-
1.0
-
0.005
µ
A
I
CC
Supply Current
V
CC
=
15V
0.05
300
µ
A
CMOS/LPTTL INTERFACE
V
IN(1)
Logical "1" Input Voltage
V
CC
=
4.75V
V
CC
-
1.5
V
V
IN(0)
Logical "0" Input Voltage
V
CC
=
4.75V
0.8
V
V
OUT(1)
Logical "1" Output Voltage
V
CC
=
4.75V, I
O
=
-
50
µ
A
2.4
V
(RB Output Only)
V
OUT(0)
Logical "0" Output Voltage
V
CC
=
4.75V, I
O
=
360
µ
A
0.4
V
OUTPUT DRIVE (See Family Characteristics Data Sheet)
I
SOURCE
Output Source Current
V
CC
=
4.75V, V
OUT
=
0.4V
-
0.80
mA
(P-Channel) (RB Output Only)
V
CC
=
10V, V
OUT
=
0.5V
-
4.0
mA
I
SINK
Output Sink Current
V
CC
=
5.0V, V
OUT
=
V
CC
1.75
3.6
mA
(N-Channel)
T
A
=
25
°
C
I
SINK
Output Sink Current
V
CC
=
10V, V
OUT
=
V
CC
8.0
16
mA
(N-Channel)
T
A
=
25
°
C
I
SOURCE
Output Source Current
V
CC
=
5.0V, V
OUT
=
3.4V
-
20
-
50
mA
(NPN Bipolar)
V
CC
=
5.0V, V
OUT
=
3.0V
-
65
mA
V
CC
=
10V, V
OUT
=
8.4V
-
20
-
50
mA
V
CC
=
10V, V
OUT
=
8.0V
-
65
mA
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4
MM
74C48
AC Electrical Characteristics
(Note 7)
T
A
=
25
°
C, C
L
=
50 pF, unless otherwise specified
Note 7: AC Parameters are guaranteed by DC correlated testing.
Typical Applications
Typical Connection Utilizing
the Ripple-Blanking Feature
First three stages will blank leading zeros, the fourth stage will not blank zeros.
Blanking Input Connection Diagram
When RBO/BI is forced LOW, all segment outputs are off regardless of the state of any other input condition.
Symbol
Parameter
Conditions
Min
Typ
Max
Units
t
pd0,
t
pd1
Propagation Delay to a "1" or "0" on
V
CC
=
5.0V
450
1500
ns
Segment Outputs from Data Inputs
V
CC
=
10V
160
500
ns
t
pd0
Propagation Delay to a "0" on
V
CC
=
5.0V
500
1600
ns
Segment Outputs from RB Input
V
CC
=
10V
180
550
ns
t
pd0
Propagation Delay to a "0" on
V
CC
=
5.0V
350
1200
ns
Segment Outputs from Blanking Input
V
CC
=
10V
140
450
ns
t
pd1
Propagation Delay to a "1" on
V
CC
=
5.0V
450
1500
ns
Segment Outputs from Lamp Test
V
CC
=
10V
160
500
ns
t
pd1
Propagation Delay to a "1" on RB
V
CC
=
5.0V
600
2000
ns
Output from RB Input
V
CC
=
10V
250
800
ns
t
pd0
Propagation Delay to a "0" on RB
V
CC
=
5.0V
140
450
ns
Output from RB Input
V
CC
=
10V
50
150
ns
5
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MM74C48
Light Emitting Diode (LED) Readout
Incandescent Readout
**A filament pre-warm resistor is recommended to reduce filament thermal
shock and increase the effective cold resistance of the filament.
Fluorescent Readout
Gas Discharge Readout
Liquid Crystal (LC) Readout
Direct DC drive of LC's not recommended for life of LC readouts.
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