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TL/F/8442 5 4 L S 2 4 4 / D M 7 4 L S 2 4 4 O c ta l T R I-S T A T E B u ffe rs / L in e D riv e rs / L in e R e c e iv e rs August 1989 54LS244/DM74LS244 Octal TRI-STATEÉ Buffers/Line Drivers/Line Receivers General Description These buffers/line drivers are designed to improve both the performance and PC board density of TRI-STATE buffers/ drivers employed as memory-address drivers, clock drivers, and bus-oriented transmitters/receivers. Featuring 400 mV of hysteresis at each low current PNP data line input, they provide improved noise rejection and high fanout outputs and can be used to drive terminated lines down to 133X. Features Y TRI-STATE outputs drive bus lines directly Y PNP inputs reduce DC loading on bus lines Y Hysteresis at data inputs improves noise margins Y Typical IOL (sink current) 54LS 12 mA 74LS 24 mA Y Typical IOH (source current) 54LS b12 mA 74LS b15 mA Y Typical propagation delay times Inverting 10.5 ns Noninverting 12 ns Y Typical enable/disable time 18 ns Y Typical power dissipation (enabled) Inverting 130 mW Noninverting 135 mW Connection Diagram Dual-In-Line Package TL/F/8442–1 Order Number 54LS244DMQB, 54LS244FMQB, 54LS244LMQB, DM74LS244WM or DM74LS244N See NS Package Number E20A, J20A, M20B, N20A or W20A Function Table Inputs Output G A Y L L L L H H H X Z L e Low Logic Level H e High Logic Level X e Either Low or High Logic Level Z e High Impedance TRI-STATEÉ is a registered trademark of National Semiconductor Corporation. C1995 National Semiconductor Corporation RRD-B30M105/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 54LS b55§C to a125§C DM74LS 0§C to a70§C Storage Temperature Range b65§C to a150§C Note: The ‘‘Absolute Maximum Ratings’’ are those values beyond which the safety of the device cannot be guaran- teed. 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 Parameter 54LS244 DM74LS244 Units Min Nom Max Min Nom Max VCC Supply Voltage 4.5 5 5.5 4.75 5 5.25 V VIH High Level Input Voltage 2 2 V VIL Low Level Input Voltage 0.7 0.8 V IOH High Level Output Current b12 b15 mA IOL Low Level Output Current 12 24 mA TA Free Air Operating Temperature b55 125 0 70 §C Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted) Symbol Parameter Conditions Min Typ Max Units (Note 1) VI Input Clamp Voltage VCC e Min, II e b18 mA b1.5 V HYS Hysteresis (VTa b VTb) VCC e Min 0.2 0.4 V Data Inputs Only VOH High Level Output Voltage VCC e Min, VIH e Min DM74 2.7 VIL e Max, IOH e b1 mA VCC e Min, VIH e Min 54LS/DM74 2.4 3.4 V VIL e Max, IOH e b3 mA VCC e Min, VIH e Min 54LS/DM74 2 VIL e 0.5V, IOH e Max VOL Low Level Output Voltage VCC e Min IOL e 12 mA 54LS/DM74 0.4 VIL e Max VIOL e Max DM74 0.5 VIH e Min IOZH Off-State Output Current, VCC e Max VO e 2.7V 20 mA High Level Voltage Applied VIL e Max IOZL Off-State Output Current, VIH e Min VO e 0.4V b20 mA Low Level Voltage Applied II Input Current at Maximum VCC e Max VI e 7V (DM74) 0.1 mA Input Voltage VI e 10V (54LS) IIH High Level Input Current VCC e Max VI e 2.7V 20 mA IIL Low Level Input Current VCC e Max VI e 0.4V b0.5 b200 mA IOS Short Circuit Output Current VCC e Max (Note 2) 54LS b50 b225 mA DM74 b40 ICC Supply Current VCC e Max, Outputs High 13 23 Outputs Open Outputs Low 27 46 mA Outputs Disabled 32 54 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 at VCC e 5V, TA e 25§C (see Section 1 for Test Waveforms and Output Load) Symbol Parameter Conditions 54LS Max DM74LS Max Units tPLH Propagation Delay Time CL e 45 pF 18 18 ns Low to High Level Output RL e 667X tPHL Propagation Delay Time CL e 45 pF 18 18 ns High to Low Level Output RL e 667X tPZL Output Enable Time to CL e 45 pF 30 30 ns Low Level RL e 667X tPZH Output Enable Time to CL e 45 pF 23 23 ns High Level RL e 667X tPLZ Output Disable Time CL e 5 pF 25 25 ns from Low Level RL e 667X tPHZ Output Disable Time CL e 5 pF 18 18 ns from High Level RL e 667X tPLH Propagation Delay Time CL e 150 pF 21 ns Low to High Level Output RL e 667X tPHL Propagation Delay Time CL e 150 pF 22 ns High to Low Level Output RL e 667X tPZL Output Enable Time to CL e 150 pF 33 ns Low Level RL e 667X tPZH Output Enable Time to CL e 150 pF 26 ns High Level RL e 667X Note: 54LS Output Load is CL e 50 pF for tPLH, tPHL, tPZL and tPZH. 3 Physical Dimensions inches (millimeters) Ceramic Leadless Chip Carrier Package (E) Order Number 54LS244LMQB NS Package Number E20A 20-Lead Ceramic Dual-In-Line Package (J) Order Number 54LS244DMQB NS Package Number J20A 4 Physical Dimensions inches (millimeters) (Continued) 20-Lead Wide Small Outline Molded Package (M) Order Number DM74LS244WM NS Package Number M20B 20-Lead Molded Dual-In-Line Package (N) Order Number DM74LS244N NS Package Number N20A 5 5 4 L S 2 4 4 / D M 7 4 L S 2 4 4 O c ta l T R I- S T A T E B u ff e rs / L in e D ri v e rs / L in e R e c e iv e rs Physical Dimensions inches (millimeters) (Continued) 20-Lead Ceramic Flat Package (W) Order Number 54LS244FMQB NS Package Number W20A 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 2. A critical component is any component of a life systems which, (a) are intended for surgical implant support device or system whose failure to perform can into the body, or (b) support or sustain life, and whose be reasonably expected to cause the failure of the life failure to perform, when properly used in accordance support device or system, or to affect its safety or with instructions for use provided in the labeling, can effectiveness. be reasonably expected to result in a significant injury to the user. National Semiconductor National Semiconductor National Semiconductor National Semiconductor Corporation Europe Hong Kong Ltd. Japan Ltd. 1111 West Bardin Road Fax: (a49) 0-180-530 85 86 13th Floor, Straight Block, Tel: 81-043-299-2309 Arlington, TX 76017 Email: cnjwge@ tevm2.nsc.com Ocean Centre, 5 Canton Rd. Fax: 81-043-299-2408 Tel: 1(800) 272-9959 Deutsch Tel: (a49) 0-180-530 85 85 Tsimshatsui, Kowloon Fax: 1(800) 737-7018 English Tel: (a49) 0-180-532 78 32 Hong Kong Fran3ais Tel: (a49) 0-180-532 93 58 Tel: (852) 2737-1600 Italiano Tel: (a49) 0-180-534 16 80 Fax: (852) 2736-9960 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.