74LS48

DM74LS48 BCD to 7-Segment Decoder January 1992 DM74LS48 BCD to 7-Segment Decoder General Description The ’LS48 translates four lines of BCD (8421) input data into the 7-segment numeral code and provides seven corresponding outputs having pull-up resistors as opposed to totem pole pull-ups These outputs can serve as logic signals with a HIGH output corresponding to a lighted lamp segment or can provide a 1 3 mA base current to npn lamp driver transistors Auxiliary inputs provide lamp test blanking and cascadable zero-suppression functions The ’LS48 decodes the input data in the pattern indicated in the Truth Table and the segment identification illustration Connection Diagram Dual-In-Line Package TL F 10172 – 1 Order Number DM74LS48M or DM74LS48N See NS Package Number M16A or N16E C1995 National Semiconductor Corporation TL F 10172 RRD-B30M105 Printed in U S A Absolute Maximum Ratings (Note) Supply Voltage Input Voltage Operating Free Air Temperature Range DM74LS Storage Temperature Range 7V 7V 0 C to a 70 C b 65 C to a 150 C 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 for actual device operation Recommended Operating Conditions Symbol VCC VIH VIL IOH IOL TA Parameter Min Supply Voltage High Level Input Voltage Low Level Input Voltage High Level Output Current Low Level Output Current Free Air Operating Temperature 0 4 75 2 08 b 50 DM74LS48 Nom 5 Max 5 25 Units V V V mA mA C 60 70 Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted) Symbol VI VOH IOFF VOL 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 Min IOH e Max VIL e Max VCC e Min VO e 0 85V VCC e Min IOL e Max VIH e Min IOL e 2 0 mA VCC e Min II IIH IIL IOS ICCH Input Current Input Voltage Max VCC e Max VI e 7V VCC e Max VI e 2 7V VCC e Max VI e 0 4V VCC e Max VO e 0V at BI RBO (Note 2) VCC e Max VIN e 4 5V b0 3 Min Typ (Note 1) Max b1 5 Units V V mA 24 b1 3 05 04 01 20 b0 4 b2 V mA mA mA mA mA High Level Input Current Low Level Input Current Short Circuit Output Current Supply Current 38 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 Switching Characteristics at VCC e 5V and TA e 25 C Symbol tPLH tPHL tPLH tPHL Note LT e HIGH A0 –A3 e HIGH Parameter Min Propagation Delay Time An to a–g Propagation Delay Time RBI to a–f CL e 15 pF Max 100 100 100 100 Units ns ns 2 Numerical Designations Resultant Displays TL F 10172 – 4 Truth Table Decimal Or Function 0 (Note 1) 1 (Note 1) 2 3 4 5 6 7 8 9 10 11 12 13 14 15 BI (Note 2) RBI (Note 3) LT (Note 4) Inputs LT H H H H H H H H H H H H H H H H X H L RBI H X X X X X X X X X X X X X X X X L X A3 L L L L L L L L H H H H H H H H X L X A2 L L L L H H H H L L L L H H H H X L X A1 L L H H L L H H L L H H L L H H X L X A0 L H L H L H L H L H L H L H L H X L X BI RBO H H H H H H H H H H H H H H H H L L H a H L H H L H L H H H L L L H L L L L H b H H H H H L L H H H L L H L L L L L H c H H L H H H H H H H L H L L L L L L H Outputs d H L H H L H H L H L H H L H H L L L H e H L H L L L H L H L H L L L H L L L H f H L L L H H H L H H L L H H H L L L H g L L H H H H H L H H H H H H H L L L H Note 1 BI RBO is wired-AND logic serving as blanking input (BI) and or ripple-blanking output (RBO) The blanking out (BI) must be open or held at a HIGH level when output functions 0 through 15 are desired and ripple-blanking input (RBI) must be open or at a HIGH level if blanking of a decimal 0 is not desired X e input may be HIGH or LOW Note 2 When a LOW level is applied to the blanking input (forced condition) all segment outputs go to a LOW level regardless of the state of any other input condition Note 3 When ripple-blanking input (RBI) and inputs A0 A1 A2 and A3 are at LOW level with the lamp test input at HIGH level all segment outputs go to a LOW level and the ripple-blanking output (RBO) goes to a LOW level (response condition) Note 4 When the blanking input ripple-blanking output (BI RBO) is open or held at a HIGH level and a LOW level is applied to lamp test input all segment outputs go to a HIGH level Logic Symbol TL F 10172 – 2 VCC e Pin 16 GND e Pin 8 3 Logic Diagram TL F 10172 – 3 4 Physical Dimensions inches (millimeters) 16-Lead Small Outline Molded Package (M) Order Number DM74LS48M NS Package Number M16A 5 DM74LS48 BCD to 7-Segment Decoder Physical Dimensions inches (millimeters) (Continued) 16-Lead Molded Dual-In-Line Package (N) Order Number DM74LS48N NS Package Number N16E LIFE SUPPORT POLICY NATIONAL’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 NATIONAL SEMICONDUCTOR CORPORATION As used herein 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 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 National Semiconductor Corporation 1111 West Bardin Road Arlington TX 76017 Tel 1(800) 272-9959 Fax 1(800) 737-7018 2 A critical component is 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 National Semiconductor Europe Fax (a49) 0-180-530 85 86 Email cnjwge tevm2 nsc com Deutsch Tel (a49) 0-180-530 85 85 English Tel (a49) 0-180-532 78 32 Fran 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