DM74LS245 3-STATE Octal Bus Transceiver General Description These octal bus transceivers are designed for asynchronous two-way communication between data buses. The control function implementation minimizes external timing requirements. The device allows data transmission from the A bus to the B bus or from the B bus to the A bus depending upon the logic level at the direction control (DIR) input. The enable input (G)can be used to disable the device so that the buses are effectively isolated. Features n Bi-Directional bus transceiver in a high-density 20-pin package 3-STATE outputs drive bus lines directly PNP inputs reduce DC loading on bus lines Hysteresis at bus inputs improve noise margins Typical propagation delay times, port-to-port 8 ns Typical enable/disable times 17 ns IOL (sink current) 54LS 12 mA 74LS 24 mA n IOH (source current) 54LS −12 mA 74LS −15 mA n Alternate Military/Aerospace device (54LS245) is available. Contact a Fairchild Semiconductor Sales Office/Distributor for specifications. n n n n n n Connection Diagram Dual-In-Line Package DS006413-1 Order Number 54LS245DMQB, 54LS245FMQB, 54LS245LMQB, DM54LS245J, DM54LS245W, DM74LS245WM or DM74LS245N See Package Number E20A, J20A, M20B, N20A or W20A Function Table Enable Direction G Control Operation DIR L L B data to A bus L H A data to B bus H X Isolation H = High Level, L = Low Level, X = Irrelevant © 1998 Fairchild Semiconductor Corporation DS006413 www.fairchildsemi.com DM74LS245 3-STATE Octal Bus Transceiver March 1998 Absolute Maximum Ratings (Note 1) Supply Voltage Input Voltage DIR or G A or B Operating Free Air Temperature Range DM54LS and 54LS DM74LS Storage Temperature Range 7V 7V 5.5V −55˚C to +125˚C 0˚C to +70˚C −65˚C to +150˚C Recommended Operating Conditions Symbol Parameter DM54LS245 DM74LS245 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 −12 −15 mA IOL Low Level Output Current 24 mA TA Free Air Operating Temperature 70 ˚C 2 V 2 V 12 −55 125 0 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” table are not guaranteed at the absolute maximum ratings. The “Recommended Operating Conditions” table will define the conditions for actual device operation. Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted) Symbol Parameter Conditions Min Typ Max Units −1.5 V (Note 2) VI Input Clamp Voltage HYS Hysteresis (VT+ − VT−) VOH High Level Output Voltage VCC = Min, II = −18 mA VCC = Min VCC = Min, VIH = Min VIL = Max, IOH = −1 mA VCC = Min, VIL = Min VIL = Max, IOH = −3 mA VCC = Min, VIH = Min VOL IOZH Low Level Output Voltage Off-State Output Current, High Level Voltage Applied IOZL Off-State Output Current, VIL = 0.5V, IOH = Max VCC = Min IOL = 12 mA VIL = Max IOL = Max 0.2 DM74 2.7 DM54/DM74 2.4 DM54/DM74 2 0.4 V 3.4 V DM74 0.4 DM54 0.4 DM74 0.5 V VIH = Min VCC = Max VO = 2.7V 20 µA VIL = Max VIH = Min VO = 0.4V −200 µA 0.1 mA Low Level Voltage Applied II Input Current at Maximum VCC = Max Input Voltage A or B DIR or G IIH High Level Input Current IIL Low Level Input Current IOS Short Circuit Output Current VCC = Max, VI = 2.7V VCC = Max, VI = 0.4V VCC = Max (Note 3) ICC Supply Current Outputs High VI = 5.5V VI = 7V −40 VCC = Max 20 µA −0.2 mA −225 mA 48 70 Outputs Low 62 90 Outputs at Hi-Z 64 95 Note 2: All typicals are at VCC = 5V, TA = 25˚C. Note 3: Not more than one output should be shorted at a time, not to exceed one second duration www.fairchildsemi.com 0.1 2 mA Switching Characteristics VCC = 5V, TA = 25˚C DM54/74 Symbol Parameter Conditions LS245 Min tPLH Propagation Delay Time, Low-to-High-Level Output tPHL Propagation Delay Time, High-to-Low-Level Output tPZL Output Enable Time to Low Level tPZH Output Enable Time to High Level tPLZ Output Disable Time from Low Level tPHZ Output Disable Time from High Level tPLH Propagation Delay Time, Low-to-High-Level Output tPHL Propagation Delay Time, High-to-Low-Level Output tPZL Output Enable Time to Low Level tPZH Output Enable Time to High Level CL = 45 pF RL = 667Ω CL = 5 pF RL = 667Ω 3 CL = 150 pF RL = 667Ω Units Max 12 ns 12 ns 40 ns 40 ns 25 ns 25 ns 16 ns 17 ns 45 ns 45 ns www.fairchildsemi.com 4 Physical Dimensions inches (millimeters) unless otherwise noted Ceramic Leadless Chip Carrier Package (E) Order Number 54LS245LMQB Package Number E20A 5 www.fairchildsemi.com Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 20-Lead Ceramic Dual-In-Line Package (J) Order Number 54LS245DMQB or DM54LS245J Package Number J20A www.fairchildsemi.com 6 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 20-Lead Small Outline Molded Package (M) Order Number DM74LS245WM Package Number M20B 20-Lead Molded Dual-In-Line Package (N) Order Number DM74LS245N Package Number N20A 7 www.fairchildsemi.com DM74LS245 3-STATE Octal Bus Transceiver Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 20-Lead Ceramic Flat Package (W) Order Number 54LS245FMQB or DM54LS245W Package Number W20A 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.