DM74ALS373 Octal D-Type TRI-STATEÉ Transparent Latch General Description These 8-bit registers feature totem-pole TRI-STATE outputs designed specifically for driving highly-capacitive or relatively low-impedance loads. The high-impedance state and increased high-logic-level drive provide these registers with the capability of being connected directly to and driving the bus lines in a bus-organized system without need for interface or pull-up components. They are particularly attractive for implementing buffer registers, I/O ports, bidirectional bus drivers, and working registers. The eight latches of the ALS373 are transparent D-type latches. While the enable (G) is high the Q outputs will follow the data (D) inputs. When the enable is taken low the output will be latched at the level of the data that was set up. A buffered output control input can be used to place the eight outputs in either a normal logic state (high or low logic levels) or a high-impedance state. In the high-impedance state the outputs neither load nor drive the bus lines significantly. The output control does not affect the internal operation of the latches. That is, the old data can be retained or new data can be entered even while the outputs are off. Features Y Y Y Y Y Y Switching specifications at 50 pF Switching specifications guaranteed over full temperature and VCC range Advanced oxide-isolated, ion-implanted Schottky TTL process Functionally and pin for pin compatible with LS TTL counterpart Improved AC performance over LS373 at approximately half the power TRI-STATE buffer-type outputs drive bus lines directly Connection Diagram Dual-In-Line Package TL/F/6220 – 1 Order Number DM74ALS373WM, DM74ALS373N or DM74ALS373SJ See NS Package Number M20B, M20D or N20A TRI-STATEÉ is a registered trademark of National Semiconductor Corporation. C1996 National Semiconductor Corporation TL/F/6220 RRD-B30M36/Printed in U. S. A. http://www.national.com DM74ALS373 Octal D-Type TRI-STATE Transparent Latch March 1996 Absolute Maximum Ratings Supply Voltage 7V Input Voltage 7V Voltage Applied to Disabled Output Operating Free Air Temperature Range DM74ALS Storage Temperature Range Typical iJA N Package M Package Note: 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. 5.5V 0§ C to a 70§ C b 65§ C to a 150§ C 57.0§ C/W 76.0§ C/W Note: This product meets application requirements of 500 temperature cycles from b 65§ C to a 150§ C. Recommended Operating Conditions Symbol Parameter VCC Supply Voltage VIH High Level Input Voltage VIL Low Level Input Voltage IOH Min Nom Max Units 4.5 5 5.5 V 2 V 0.8 V High Level Output Current b 2.6 mA IOL Low Level Output Current 24 mA tW Width of Enable Pulse, High or Low 10 ns tSU Data Setup Time 10v ns tH Data Hold Time 7v TA Free Air Operating Temperature The ( ns 0 70 §C v) arrow indicates the negative edge of the enable is used for reference. Electrical Characteristics over recommended operating free air temperature range. All typical values are measured at VCC e 5V, TA e 25§ C. Symbol Parameter Conditions VIK Input Clamp Voltage VCC e 4.5V, II e b18 mA VOH High Level Output Voltage VCC e 4.5V IOH e b2.6 mA VCC e 4.5V to 5.5V IOH e b400 mA Min 2.4 Typ Max Units b 1.5 V 3.3 V VCC b 2 VOL Low Level Output Voltage VCC e 4.5V II Input Current at Max Input Voltage VCC e 5.5V, VIH e 7V IIH High Level Input Current VCC e 5.5V, VIH e 2.7V 20 mA IIL Low Level Input Current VCC e 5.5V, VIL e 0.4V b 0.1 mA IO Output Drive Current VCC e 5.5V b 112 mA IOZH Off-State Output Current High Level Voltage Applied VCC e 5.5V VO e 2.7V 20 mA IOZL Off-State Output Current Low Level Voltage Applied VCC e 5.5V VO e 0.4V b 20 mA ICC Supply Current VCC e 5.5V Outputs Open http://www.national.com IOL e 24 mA V VO e 2.25V 2 0.35 b 30 0.5 V 0.1 mA Outputs High 9 16 mA Outputs Low 16 25 mA Outputs Disabled 17 27 mA Switching Characteristics over recommended operating free air temperature range (Note 1) Parameter Conditions tPLH Symbol Propagation Delay Time Low to High Level Output tPHL Propagation Delay Time High to Low Level Output VCC e 4.5V to 5.5V RL e 500X CL e 50 pF From tPLH To Data Any Q Data Any Q Propagation Delay Time Low to High Level Output Enable Any Q tPHL Propagation Delay Time High to Low Level Output Enable Any Q tPZH Output Enable Time to High Level Output Output Control Any Q tPZL Output Enable Time to Low Level Output Output Control Any Q tPHZ Output Disable Time from High Level Output Output Control Any Q tPLZ Output Disable Time from Low Level Output Output Control Any Q Min Max Units 2 12 ns 4 16 ns 6 22 ns 7 23 ns 6 18 ns 5 20 ns 2 10 ns 2 12 ns Note 1: See Section 5 for test waveforms and output load. Function Table Output Control Enable G D Output Q L L L H H H L X H L X X H L Q0 Z L e Low State, H e High State, X e Don’t Care Z e High Impedance State Q0 e Previous Condition of Q 3 http://www.national.com Logic Diagram TL/F/6220 – 2 http://www.national.com 4 Physical Dimensions inches (millimeters) S.O. Package (M) Order Number DM74ALS373WM NS Package Number M20B Small Outline Package (SJ) Order Number DM74ALS373SJ NS Package Number M20D 5 http://www.national.com DM74ALS373 Octal D-Type TRI-STATE Transparent Latch Physical Dimensions inches (millimeters) (Continued) Molded Dual-In-Line Package (N) Order Number DM74ALS373N NS Package Number N20A 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. 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