Revised February 2000 DM74ALS244A Octal 3-STATE Bus Driver General Description Features This octal 3-STATE bus driver is designed to provide the designer with flexibility in implementing a bus interface with memory, microprocessor, or communication systems. This device offers 64-extended temperature Grade product guaranteeing performance from −40°C to +85°C. The output 3-STATE gating control is organized into two separate groups of four buffers, and both control inputs enable the respective outputs when set logic LOW. The 3-STATE circuitry contains a feature that maintains the buffer outputs in 3-STATE (high impedance state) during power supply ramp-up or ramp-down. This eliminates bus glitching problems that arise during power-up and power-down. ■ Advanced low power Schottky TTL process oxide-isolated ion-implanted ■ Functional and pin compatible with the 74LS counterpart ■ Improved switching performance with less power dissipation compared with the 74LS counterpart ■ Switching response specified into 500Ω and 50 pF load ■ Switching response specifications guaranteed over full temperature and VCC supply range ■ PNP input design reduces input loading Ordering Code: Order Number Package Number DM74ALS244AWM M20B DM74ALS244ASJ M20D DM74ALS244AMSA DM74ALS244AN Package Description 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide MSA20 20-Lead Shrink Small Outline Package (SSOP), EIAJ TYPE II, 5.3mm Wide N20A 20-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 Logic Diagram Function Table Input Output G A L L Y L L H H H X Z H = HIGH Level Logic State L = LOW Level Logic State X = Don't Care (Either LOW or HIGH Level Logic State) Z = High Impedance (OFF) State © 2000 Fairchild Semiconductor Corporation DS006212 www.fairchildsemi.com DM74ALS244A Octal 3-STATE Bus Driver September 1986 DM74ALS244A Absolute Maximum Ratings(Note 1) Supply Voltage, VCC 7V Input Voltage 7V Voltage Applied to Disabled Output 5.5V Note 1: 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. 0°C to +70°C Operating Free Air Temperature Range −65°C to +150°C Storage Temperature Range Typical θJA N Package 60.5°C/W M Package 79.8°C/W Recommended Operating Conditions Symbol Parameter Min Typ Max 4.5 5 5.5 Units VCC Supply Voltage VIH HIGH Level Input Voltage V VIL LOW Level Input Voltage 0.8 V IOH HIGH Level Output Current −15 mA IOL LOW Level Output Current 24 mA TA Operating Free-Air Temperature 70 °C 2 V 0 Electrical Characteristics over recommended operating free air temperature (unless otherwise specified) Symbol Parameter Conditions Min VIK Input Clamp Voltage VCC = 4.5V, II = −18 mA VOH HIGH Level VCC = 4.5V to 5.5V IOH = −0.4 mA Output Voltage VCC = 4.5V IOH = −3 mA LOW Level VCC = 4.5V Output Voltage IOL = 24 mA Max Units −1.5 V VCC−2 V 2.4 V 2 V IOH = Max VOL Typ 0.35 0.5 V mA II Input Current at Maximum Input Voltage VCC = 5.5V, VI = 7V 0.1 IIH HIGH Level Input Current VCC = 5.5V, VI = 2.7V 20 µA IIL LOW Level Input Current VCC = 5.5V, VIL = 0.4V −0.1 mA IO Output Drive Current VCC = 5.5V, VO = 2.25V −112 mA IOZH HIGH Level 3-STATE Output Current VCC = 5.5V, VO = 2.7V 20 µA IOZL LOW Level 3-STATE Output Current VCC = 5.5V, VO = 0.4V −20 µA ICC Supply Current VCC = 5.5V 9 15 mA Outputs LOW 15 24 mA Outputs 3-STATE 17 27 mA −30 Outputs HIGH Switching Characteristics over recommended operating free-air temperature range Symbol tPLH Parameter Conditions Propagation Delay Time VCC = 4.5V to 5.5V, LOW-to-HIGH Level Output CL = 50 pF, From (Input) To (Output) Min Max Units A Y 3 10 ns A Y 3 10 ns Propagation Delay Time R1 = 500Ω, HIGH-to-LOW Level Output R2 = 500Ω, tPZH Output Enable Time to HIGH Level Output TA = Min to Max G Y 3 20 ns tPZL Output Enable Time to LOW Level Output G Y 3 20 ns tPHZ Output Disable Time from HIGH Level Output G Y 2 10 ns tPLZ Output Disable Time from LOW Level Output G Y 1 13 ns tPHL www.fairchildsemi.com 2 DM74ALS244A Physical Dimensions inches (millimeters) unless otherwise noted 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide Package Number M20B 3 www.fairchildsemi.com DM74ALS244A Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide Package Number M20D www.fairchildsemi.com 4 DM74ALS244A Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 20-Lead Shrink Small Outline Package (SSOP), EIAJ TYPE II, 5.3mm Wide Package Number MSA20 5 www.fairchildsemi.com DM74ALS244A Octal 3-STATE Bus Driver Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide Package Number N20A 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