DM74LS155N

Revised April 2000 DM74LS155 • DM74LS156 Dual 2-Line to 4-Line Decoders/Demultiplexers General Description Features These TTL circuits feature dual 1-line-to-4-line demultiplexers with individual strobes and common binary-address inputs in a single 16-pin package. When both sections are enabled by the strobes, the common address inputs sequentially select and route associated input data to the appropriate output of each section. The individual strobes permit activating or inhibiting each of the 4-bit sections as desired. Data applied to input C1 is inverted at its outputs and data applied at C2 is true through its outputs. The inverter following the C1 data input permits use as a 3-to-8line decoder, or 1-to-8-line demultiplexer, without external gating. Input clamping diodes are provided on these circuits to minimize transmission-line effects and simplify system design. ■ Applications: Dual 2-to-4-line decoder Dual 1-to-4-line demultiplexer 3-to-8-line decoder 1-to-8-line demultiplexer ■ Individual strobes simplify cascading for decoding or demultiplexing larger words ■ Input clamping diodes simplify system design ■ Choice of outputs: Totem-pole (DM74LS155) Open-collector (DM74LS156) Ordering Code: Order Number DM74LS155M Package Number Package Description M16A 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow DM74LS155N N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide DM74LS156M M16A 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow DM74LS156N N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code. Connection Diagram © 2000 Fairchild Semiconductor Corporation DS006395 www.fairchildsemi.com DM74LS155 • DM74LS156 Dual 2-Line to 4-Line Decoders/Demultiplexers August 1986 DM74LS155 • DM74LS156 Function Tables 3-Line-to-8-Line Decoder or 1-Line-to-8-Line Demultiplexer Inputs Outputs Strobe Select Or Data (0) (1) (2) (3) (4) (5) (6) (7) C (Note 1) B A G (Note 2) 2Y0 2Y1 2Y2 2Y3 1Y0 1Y1 1Y2 1Y3 X X X H H H H H H H H H L L L L L H H H H H H H L L H L H L H H H H H H L H L L H H L H H H H H L H H L H H H L H H H H H L L L H H H H L H H H H L H L H H H H H L H H H H L L H H H H H H L H H H H L H H H H H H H L 2-Line-to-4-Line Decoder or 1-Line-to-4-Line Demultiplexer Inputs Select Outputs Strobe Data C1 B A G1 X X H L L L Inputs 1Y0 1Y1 1Y2 1Y3 X H H H H L H H Select Outputs Strobe Data 2Y0 2Y1 2Y2 2Y3 B A G2 C2 H X X H X H H H H H L L L L L H H H L H L H H L H H L H L L H L H H H L L H H H L H H L L L H H L H H H L H H H H L H H L L H H H L X X X L H H H H X X X H H H H H H = HIGH level L = LOW level X = don’t care Note 1: C = inputs C1 and C2 connected together Note 2: G = inputs G1 and G2 connected together Logic Diagram www.fairchildsemi.com 2 Supply Voltage Note 3: 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 7V 0°C to +70°C Operating Free Air Temperature Range −65°C to +150°C Storage Temperature Range DM74LS155 Recommended Operating Conditions Symbol Parameter Min Nom Max 4.75 5 5.25 Units VCC Supply Voltage VIH HIGH Level Input Voltage V VIL LOW Level Input Voltage 0.8 V VOH HIGH Level Output Current −0.4 mA IOL LOW Level Output Current 8 mA TA Free Air Operating Temperature 70 °C 2 V 0 DM74LS155 Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted) Symbol Parameter Conditions VI Input Clamp Voltage VCC = Min, II = −18 mA VOH HIGH Level VCC = Min, IOH = Max Output Voltage VIL = Max, VIH = Min VOL LOW Level VCC = Min, IOL = Max Output Voltage VIL = Max, VIH = Min Min Typ (Note 4) Max −1.5 2.7 IOL = 4 mA, VCC = Min 3.4 Units V V 0.35 0.5 0.25 0.4 V II Input Current @ Max Input Voltage VCC = Max, VI = 7V 0.1 IIH HIGH Level Input Current VCC = Max, VI = 2.7V 20 µA IIL LOW Level Input Current VCC = Max, VI = 0.4V −0.36 mA IOS Short Circuit Output Current VCC = Max (Note 5) −100 mA ICC Supply Current VCC = Max (Note 6) 10 mA −20 6.1 mA 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. Note 6: ICC is measured with all outputs OPEN, A,B, and C1 inputs at 4.5V, and C2, G1, and G2 inputs GROUNDED. DM74LS155 Switching Characteristics at VCC = 5V and TA = 25°C RL = 2 kΩ From (Input) Symbol Parameter To (Output) CL = 15 pF Min tPLH Propagation Delay Time LOW-to-HIGH Level Output tPHL Propagation Delay Time HIGH-to-LOW Level Output tPLH Propagation Delay Time LOW-to-HIGH Level Output tPHL Propagation Delay Time HIGH-to-LOW Level Output tPLH tPHL A, B, C2, G1 or G2 to Y A, B, C2, G1 or G2 to Y A or B to Y A or B to Y Propagation Delay Time C1 LOW-to-HIGH Level Output to Y Propagation Delay Time C1 HIGH-to-LOW Level Output to Y 3 Max CL = 50 pF Min Units Max 18 22 ns 27 35 ns 18 24 ns 27 35 ns 20 24 ns 27 35 ns www.fairchildsemi.com DM74LS155 • DM74LS156 Absolute Maximum Ratings(Note 3) DM74LS155 • DM74LS156 DM74LS156 Recommended Operating Conditions Symbol Parameter Min Nom Max 4.75 5 5.25 Units VCC Supply Voltage VIH HIGH Level Input Voltage V VIL LOW Level Input Voltage 0.8 V VOH HIGH Level Output Voltage 5.5 V IOL LOW Level Output Current 8 mA TA Free Air Operating Temperature 70 °C 2 V 0 DM74LS156 Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted) Symbol Parameter Conditions VI Input Clamp Voltage VCC = Min, II = −18 mA ICEX HIGH Level VCC = Min, VO = 5.5V VOL Output Current VIL = Max, VIH = Min LOW Level VCC = Min, IOL = Max Output Voltage VIL = Max, VIH = Min Min IOL = 4 mA, VCC = Min Typ (Note 7) Max Units −1.5 V 100 µA 0.35 0.5 0.25 0.4 V II Input Current @ Max Input Voltage VCC = Max, VI = 7V 0.1 IIH HIGH Level Input Current VCC = Max, VI = 2.7V 20 µA IIL LOW Level Input Current VCC = Max, VI = 0.4V −0.36 mA ICC Supply Current VCC = Max (Note 8) 10 mA 6.1 mA Note 7: All typicals are at VCC = 5V, TA = 25° C. Note 8: ICC is measured with all outputs OPEN, A, B, and C1 inputs at 4.5V, and C2, G1, and G2 GROUNDED. DM74LS156 Switching Characteristics at VCC = 5V and TA = 25°C RL = 2 kΩ From (Input) Symbol Parameter To (Output) CL = 15 pF Min tPLH Propagation Delay Time LOW-to-HIGH Level Output tPHL Propagation Delay Time HIGH-to-LOW Level Output tPLH Propagation Delay Time LOW-to-HIGH Level Output tPHL Propagation Delay Time HIGH-to-LOW Level Output tPLH tPHL A, B, C2, G1 or G2 to Y A, B, C2, G1 or G2 to Y A or B to Y A or B to Y Propagation Delay Time C1 LOW-to-HIGH Level Output to Y Propagation Delay Time C1 HIGH-to-LOW Level Output to Y www.fairchildsemi.com 4 Max CL = 50 pF Min Units Max 28 53 ns 33 43 ns 28 53 ns 33 43 ns 28 53 ns 34 43 ns DM74LS155 • DM74LS156 Physical Dimensions inches (millimeters) unless otherwise noted 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow Package Number M16A 5 www.fairchildsemi.com DM74LS155 • DM74LS156 Dual 2-Line to 4-Line Decoders/Demultiplexers Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 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. www.fairchildsemi.com www.fairchildsemi.com 6