Fairchild DM7446 Bcd to 7-segment decoders/driver Datasheet

Revised February 2000
DM7446A, DM7447A
BCD to 7-Segment Decoders/Drivers
General Description
Features
The DM7446A and DM7447A feature active-LOW outputs
designed for driving common-anode LEDs or incandescent
indicators directly. All of the circuits have full ripple-blanking input/output controls and a lamp test input. Segment
identification and resultant displays are shown on a following page. Display patterns for BCD input counts above nine
are unique symbols to authenticate input conditions.
■ All circuit types feature lamp intensity modulation capability
■ Open-collector outputs drive indicators directly
■ Lamp-test provision
■ Leading/trailing zero suppression
All of the circuits incorporate automatic leading and/or trailing-edge, zero-blanking control (RBI and RBO). Lamp test
(LT) of these devices may be performed at any time when
the BI/RBO node is at a HIGH logic level. All types contain
an overriding blanking input (BI) which can be used to control the lamp intensity (by pulsing) or to inhibit the outputs.
Ordering Code:
Order Number
Package Number
Package Description
DM7446AN
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
DM7446AN
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Connection Diagram
© 2000 Fairchild Semiconductor Corporation
DS006518
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DM7446A, DM7447A BCD to 7-Segment Decoders/Drivers
September 1986
DM7446A, DM7447A
Function Table
Decimal or
Inputs
BI/RBO
A
(Note 1)
Outputs
Function
LT
RBI
D
C
B
a
b
c
d
e
f
g
0
H
H
L
L
L
L
H
L
L
L
L
L
L
H
1
H
X
L
L
L
H
H
H
L
L
H
H
H
H
2
H
X
L
L
H
L
H
L
L
H
L
L
H
L
3
H
X
L
L
H
H
H
L
L
L
L
H
H
L
4
H
X
L
H
L
L
H
H
L
L
H
H
L
L
5
H
X
L
H
L
H
H
L
H
L
L
H
L
L
6
H
X
L
H
H
L
H
H
H
L
L
L
L
L
7
H
X
L
H
H
H
H
L
L
L
H
H
H
H
8
H
X
H
L
L
L
H
L
L
L
L
L
L
L
9
H
X
H
L
L
H
H
L
L
L
H
H
L
L
10
H
X
H
L
H
L
H
H
H
H
L
L
H
L
11
H
X
H
L
H
H
H
H
H
L
L
H
H
L
12
H
X
H
H
L
L
H
H
L
H
H
H
L
L
13
H
X
H
H
L
H
H
L
H
H
L
H
L
L
14
H
X
H
H
H
L
H
H
H
H
L
L
L
L
15
H
X
H
H
H
H
H
H
H
H
H
H
H
H
Note
(Note 2)
BI
X
X
X
X
X
X
L
H
H
H
H
H
H
H
(Note 3)
RBI
H
L
L
L
L
L
L
H
H
H
H
H
H
H
(Note 4)
LT
L
X
X
X
X
X
H
L
L
L
L
L
L
L
(Note 5)
H = HIGH level,
L = LOW level,
X = Don’t Care
Note 1: BI/RBO is a wire-AND logic serving as blanking input (BI) and/or ripple-blanking output (RBO).
Note 2: The blanking input (BI) must be OPEN or held at a HIGH logic level when output functions 0 through 15 are desired. The ripple-blanking input (RBI)
must be OPEN or 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 HIGH 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 H 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 or held HIGH and a LOW is applied to the lamp-test input, all segment outputs are
L.
Logic Diagram
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2
Supply Voltage
Note 6: The “Absolute Maximum Ratings” are those values beyond which
the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommended Operating Conditions” table will define the conditions
for actual device operation.
7V
Input Voltage
5.5V
Operating Free Air Temperature Range
Storage Temperature Range
0°C to +70°C
−65°C to +150°C
Recommended Operating Conditions
Symbol
Parameter
Min
Nom
Max
Units
4.75
5
5.25
V
0.8
V
DM7446A
VCC
Supply Voltage
VIH
HIGH Level Input Voltage
VIL
LOW Level Input Voltage
VOH
HIGH Level Output Voltage (a thru g)
30
V
IOH
HIGH Level Output Current (BI/RBO)
−0.2
µA
IOL
LOW Level Output Current (a thru g)
40
mA
IOL
LOW Level Output Current (BI/RBO)
8
mA
TA
Free Air Operating Temperature
70
°C
5.25
V
0.8
V
2
V
0
DM7447A
VCC
Supply Voltage
VIH
HIGH Level Input Voltage
4.75
5
VIL
LOW Level Input Voltage
VOH
HIGH Level Output Voltage (a thru g)
15
V
IOH
HIGH Level Output Current (BI/RBO)
−0.2
µA
IOL
LOW Level Output Current (a thru g)
40
mA
IOL
LOW Level Output Current (BI/RBO)
8
mA
TA
Free Air Operating Temperature
70
°C
2
0
3
V
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DM7446A, DM7447A
Absolute Maximum Ratings(Note 6)
DM7446A, DM7447A
DM7446A Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Symbol
Parameter
Conditions
VI
Input Clamp Voltage
VCC = Min, II = −12 mA
VOH
HIGH Level Output
VCC = Min
Voltage (BI/RBO)
IOH = Max
HIGH Level Output
VCC = Max, VO = 30V
Current (a thru g)
VIL = Max, VIH = Min
ICEX
VOL
II
IIH
IIL
IOS
ICC
Min
2.4
LOW Level
VCC = Min, IOL = Max
Output Voltage
VIH = Min, VIL = Max
Input Current @ Max
VCC = Max, VI = 5.5V
Input Voltage
(Except BI/RBO)
Typ
(Note 7)
Max
Units
−1.5
V
3.7
0.3
V
250
µA
0.4
V
1
mA
40
µA
HIGH Level Input
VCC = Max, VI = 2.4V
Current
(Except BI/RBO)
LOW Level Input
VCC = Max
BI/RBO
−4
Current
VI = 0.4V
Others
−1.6
Short Circuit
VCC = Max
Output Current
(BI/RBO)
VCC = Max
Supply Current
(Note 8)
mA
−4
mA
60
103
mA
Min
Max
Units
100
ns
100
ns
Note 7: All typicals are at VCC = 5V, TA = 25°C.
Note 8: ICC is measured with all outputs OPEN and all inputs at 4.5V.
DM7446A Switching Characteristics
at VCC = 5V and TA = 25°C
Symbol
tPLH
tPHL
Parameter
Conditions
Propagation Delay Time
CL = 15 pF
LOW-to-HIGH Level Output
RL = 120Ω
Propagation Delay Time
HIGH-to-LOW Level Output
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over recommended operating free air temperature range (unless otherwise noted)
Symbol
Parameter
Conditions
VI
Input Clamp Voltage
VCC = Min, II = −12 mA
VOH
HIGH Level Output
VCC = Min
Voltage (BI/RBO)
IOH = Max
ICEX
VOL
II
Min
2.4
HIGH Level Output
VCC = Max, VO = 15V
Current (a thru g)
VIL = Max, VIH = Min
LOW Level Output
VCC = Min, IOL = Max
Voltage
VIH = Min, VIL = Max
Input Current @ Max
VCC = Max, VI = 5.5V
Typ
(Note 9)
Max
Units
−1.5
V
3.7
0.3
V
250
µA
0.4
V
1
mA
Input Voltage
IIH
HIGH Level Input Current
VCC = Max, VI = 2.4V
IIL
LOW Level Input
VCC = Max
BI/RBO
−4
Current
VI = 0.4V
Others
−1.6
Short Circuit
VCC = Max
Output Current
(BI/RBO)
Supply Current
VCC = Max
IOS
ICC
40
(Note 10)
µA
mA
−4
mA
60
103
mA
Min
Max
Units
100
ns
100
ns
Note 9: All typicals are at VCC = 5V, TA = 25°C.
Note 10: ICC is measured with all outputs OPEN and all inputs at 4.5V.
DM7447A Switching Characteristics
at VCC = 5V and TA = 25°C
Symbol
tPLH
tPHL
Parameter
Conditions
Propagation Delay Time
CL = 15 pF
LOW-to-HIGH Level Output
RL = 120Ω
Propagation Delay Time
HIGH-to-LOW Level Output
5
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DM7446A, DM7447A
DM7447A Electrical Characteristics
DM7446A, DM7447A BCD to 7-Segment Decoders/Drivers
Physical Dimensions inches (millimeters) unless otherwise noted
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Package Number N16E
Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and
Fairchild reserves the right at any time without notice to change said circuitry and specifications.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD
SEMICONDUCTOR CORPORATION. As used herein:
2. A critical component in any component of a life support
device or system whose failure to perform can be reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the
body, or (b) support or sustain life, and (c) whose failure
to perform when properly used in accordance with
instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the
user.
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6
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