DM74LS47 BCD to 7-Segment Decoder/Driver with Open-Collector Outputs General Description Features 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 directly. Each 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 µA. Auxiliary inputs provided blanking, lamp test and cascadable zero-suppression functions. n n n n Open-collector outputs Drive indicator segments directly Cascadable zero-suppression capability Lamp test input Connection Diagram Dual-In-Line Package DS009817-1 Order Number DM54LS47J, DM54LS47W, DM74LS47M or DM74LS47N See Package Number J16A, M16A, N16E or W16A Pin Names Description A0–A3 BCD Inputs RBI Ripple Blanking Input (Active LOW) LT Lamp Test Input (Active LOW) BI/RBO Blanking Input (Active LOW) or Ripple Blanking Output (Active LOW) a –g *Segment Outputs (Active LOW) Note 1: *OC—Open Collector © 1998 Fairchild Semiconductor Corporation DS009817 www.fairchildsemi.com DM74LS47 BCD to 7-Segment Decoder/Driver with Open-Collector Outputs March 1998 Absolute Maximum Ratings (Note 2) Supply Voltage Input Voltage Operating Free Air Temperature Range DM54LS DM74LS Storage Temperature Range 7V 7V −55˚C to +125˚C 0˚C to +70˚C −65˚C to +150˚C Recommended Operating Conditions Symbol Parameter DM54LS47 DM74LS47 Units Min Nom Max Min Nom Max 4.5 5 5.5 4.75 5 5.25 VCC Supply Voltage VIH High Level Input Voltage VIL Low Level Input Voltage 0.7 0.8 V IOH High Level Output Current a − g @ 15V = VOH (Note 3) −50 −250 µA 2 IOH High Level Output Current BI /RBO IOL Low Level Output Current TA Free Air Operating Temperature 2 12 −55 125 V V 0 −50 µA 24 mA 70 ˚C Note 2: 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. Note 3: OFF state at a–g. Electrical Characteristics Over recommended operating free air temperature range (unless otherwise noted) Symbol Parameter Conditions Min Typ Max Units −1.5 V (Note 4) Output Voltage VCC = Min, II = −18 mA VCC = Min, IOH = Max, VIL = Max, BI /RBO Output High Current VCC = 5.5V, VO = 15V a − g VI Input Clamp Voltage VOH High Level IOFF DM54 2.4 DM74 2.7 V 3.4 250 µA Segment Outputs VOL Low Level Output Voltage Input Current @ Max II Input Voltage IIH High Level Input Current IIL Low Level Input Current IOS ICC VCC = Min, IOL = Max, VIH = Min, a − g IOL = 3.2 mA, BI /RBO DM54 0.4 DM74 0.35 DM74 0.5 0.5 IOL = 12 mA, a –g IOL = 1.6 mA, BI /RBO DM74 DM74 0.4 VCC = Max, VI = 7V VCC = Max, VI = 10V VCC = Max, VI = 2.7V VCC = Max, VI = 0.4V DM74 100 0.25 20 µA −0.4 mA mA Short Circuit VCC = Max DM54 −0.3 −2.0 (Note 5) , IOS at BI/RBO VCC = Max DM74 −0.3 −2.0 Note 4: All typicals are at VCC = 5V, TA = 25˚C. Note 5: Not more than one output should be shorted at a time, and the duration should not exceed one second. www.fairchildsemi.com 2 µA DM54 Output Current Supply Current V 0.4 13 mA Switching Characteristics at VCC = +5.0V, TA = +25˚C Symbol Parameter RL = 665Ω CL = 15 pF Conditions Min Units Max tPLH Propagation Delay 100 tPHL An to a –g 100 tPLH Propagation Delay 100 tPHL RBI to a –g (Note 6) 100 ns ns Note 6: LT = HIGH, A0–A3 = 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 data is decimal zero, a LOW signal applied to the RBI blanks the display and causes a multidigit display. For example, by grounding the RBI of the highest order decoder and connecting its BI/RBO to RBI of the next lowest order decoder, etc., leading zeros will be suppressed. Similarly, by grounding RBI of the lowest order decoder and connecting its BI/RBO to RBI of the next highest order decoder, etc., trailing zeros will be suppressed. Leading and trailing zeros can be suppressed simultaneously by using external gates, i.e.: by driving RBI of a intermediate decoder from an OR gate whose inputs are BI/RBO of the next highest and lowest order decoders. BI/RBO also serves as an unconditional blanking input. The internal NAND gate that generates the RBO signal has a resistive pull-up, as opposed to a totem pole, and thus BI/RBO can be forced LOW by external means, using wired-collector logic. A LOW signal thus applied to BI/RBO turns off all segment outputs. This blanking feature can be used to control display intensity by varying the duty cycle of the blanking signal. A LOW signal applied to LT turns on all segment outputs, provided that BI/RBO is not forced LOW. 3 www.fairchildsemi.com Logic Diagram DS009817-3 Numerical Designations—Resultant Displays DS009817-4 www.fairchildsemi.com 4 Logic Symbol DS009817-2 VCC = Pin 16 GND = Pin 8 Truth Table Decimal Inputs Outputs or Note Function LT RBI 0 H H L L L L H L L L L L L H (Note 7) 1 H X L L L H H H L L H H H H (Note 7) 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 A3 A2 A1 A0 BI/RBO a b c d e f g 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 L 11 H X H L H H H H H L L H H 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 BI X X X X X X L H H H H H H H (Note 8) RBI H L L L L L L H H H H H H H (Note 9) LT L X X X X X H L L L L L L L (Note 10) Note 7: BI/RBO is wire-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 or a decimal 0 is not desired. X = input may be HIGH or LOW. Note 8: When a LOW level is applied to the blanking input (forced condition) all segment outputs go to a HIGH level regardless of the state of any other input condition. Note 9: When ripple-blanking input (RBI) and inputs A0, A1, A2 and A3 are LOW level, with the lamp test input at HIGH level, all segment outputs go to a HIGH level and the ripple-blanking output (RBO ) goes to a LOW level (response condition). Note 10: 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 LOW level. 5 www.fairchildsemi.com Physical Dimensions inches (millimeters) unless otherwise noted 16-Lead Ceramic Dual-In-Line Package (J) Order Number DM54LS47J Package Number J16A 16-Lead Small Outline Molded Package (M) Order Number DM74LS47M Package Number M16A www.fairchildsemi.com 6 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 16-Lead Molded Dual-In-Line Package (N) Order Number DM74LS47N Package Number N16E 16-Lead Ceramic Flat Package (W) Order Number DM54LS47W Package Number W16A 7 www.fairchildsemi.com DM74LS47 BCD to 7-Segment Decoder/Driver with Open-Collector Outputs 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 1. Life support devices or systems are devices or sysdevice or system whose failure to perform can be reatems which, (a) are intended for surgical implant into sonably expected to cause the failure of the life support the body, or (b) support or sustain life, and (c) whose device or system, or to affect its safety or effectiveness. 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. Fairchild Semiconductor Corporation Americas Customer Response Center Tel: 1-888-522-5372 www.fairchildsemi.com Fairchild Semiconductor Europe Fax: +49 (0) 1 80-530 85 86 Email: [email protected] Deutsch Tel: +49 (0) 8 141-35-0 English Tel: +44 (0) 1 793-85-68-56 Italy Tel: +39 (0) 2 57 5631 Fairchild Semiconductor Hong Kong Ltd. 13th Floor, Straight Block, Ocean Centre, 5 Canton Rd. Tsimshatsui, Kowloon Hong Kong Tel: +852 2737-7200 Fax: +852 2314-0061 National Semiconductor Japan Ltd. Tel: 81-3-5620-6175 Fax: 81-3-5620-6179 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.