74Ls47
July 1992
DM54LS47 DM74LS47 BCD to 7-Segment Decoder Driver with Open-Collector Outputs
General Description
The ’LS47 accepts four lines of BCD (8421) input data generates their complements internally and decodes the data with seven AND OR gates having open-collector outputs to drive indicator segments directlyEach segment output is guaranteed to sink 24 mA in the ON (LOW) state and withstand 15V in the OFF (HIGH) state with a maximum leakage current of 250 mA Auxiliary inputs provided blanking lamp test and cascadable zero-suppression functions
Features
Y Y Y Y
Open-collector outputs Drive indicator segments directly Cascadable zero-suppression capability Lamp test input
Connection DiagramDual-In-Line Package
TL F 9817 – 1
Order Number DM54LS47J DM54LS47W DM74LS47M or DM74LS47N See NS Package Number J16A M16A N16E or W16A
Pin Names A0–A3 RBI LT BI RBO a–g
OC Open Collector
Description BCD Inputs Ripple Blanking Input (Active LOW) Lamp Test Input (Active LOW) Blanking Input (Active LOW) or Ripple Blanking Output (Active LOW) Segment Outputs (Active LOW)
C1995 NationalSemiconductor Corporation
TL F 9817
RRD-B30M115 Printed in U S A
Absolute Maximum Ratings (Note)
If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications Supply Voltage 7V Input Voltage 7V Operating Free Air Temperature Range b 55 C to a 125 C DM54LS DM74LS 0 C to a 70 C b 65 C to a 150C Storage Temperature Range Note 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’’ table are not guaranteed at the absolute maximum ratings The ‘‘Recommended Operating Conditions’’ table will define the conditions foractual device operation
Recommended Operating Conditions
Symbol VCC VIH VIL IOH IOH IOL TA Parameter Min Supply Voltage High Level Input Voltage Low Level Input Voltage High Level Output Current a b g 15V e VOH High Level Output Current BI RBO Low Level Output Current Free Air Operating Temperature
b 55
DM54LS47 Nom 5 Max 55 Min 4 75 2 07
b 50
DM74LS47 Nom 5 Max 5 25
Units V V 08
b 250b 50
45 2
V mA mA mA C
12 125 0
24 70
OFF state at a–g
Electrical Characteristics
Over recommended operating free air temperature range (unless otherwise noted) Symbol VI VOH Parameter Input Clamp Voltage High Level Output Voltage Output High Current Segment Outputs Low Level Output Voltage Conditions VCC e Min II e b18 mA VCC e Min IOH e Max VIL e Max BI RBO VCC e 5 5V VO e 15Va b g VCC e Min IOL e Max VIH e Min a b g IOL e 3 2 mA BI RBO IOL e 12 mA a– g IOL e 1 6 mA BI RBO II Input Current Input Voltage Max VCC e Max VI e 7V VCC e Max VI e 10V VCC e Max VI e 2 7V VCC e Max VI e 0 4V VCC e Max (Note 2) IOS at BI RBO VCC e Max DM54 DM74
b0 3 b0 3
Min
Typ (Note 1)
Max
b1 5
Units V V
DM54 DM74
24 27 34 250
IOFF VOL
mA
DM54 DM74 DM74 DM74 DM74DM74 DM54 0 25 0 35
04 05 05 04 04 100 20
b0 4 b2 0 b2 0
V
mA mA mA mA mA
IIH IIL IOS
High Level Input Current Low Level Input Current Short Circuit Output Current Supply Current
ICC
13
Note 1 All typicals are at VCC e 5V TA e 25 C Note 2 Not more than one output should be shorted at a time and the duration should not exceed one second
2
Switching Characteristics atVCC e a 5 0V
Symbol Parameter
TA e a 25 C RL e 665X
Conditions Min
CL e 15 pF Max 100 100 100 100
Units
tPLH tPHL tPLH tPHL
Propagation Delay An to a– g Propagation Delay RBI to a– g
ns ns
LT e HIGH A0–A3 e LOW
Functional Description
The ’LS47 decodes the input data in the pattern indicated in the Truth Table and the segment identification illustration If the input...
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