Revised February 2000 DM74ALS137 3 to 8 Line Decoder/Demultiplexer with Address Latches General Description Features The ALS137 is a three line to eight line decoder/demultiplexer with latches on the three address inputs. When the latch-enable input (GL) is LOW, the ALS137 acts as a decoder/demultiplexer. When GL goes from LOW-to-HIGH, the address present at the select inputs (A, B, and C) is stored in the latches. Further address changes are ignored as long as GL remains HIGH. The output enable controls, G1 and G2, control the state of the outputs independently of the select or latch-enable inputs. All of the outputs are HIGH unless G1 is HIGH and G2 is LOW. The ALS137 is ideally suited for implementing glitch-free decoders in strobed (stored-address) applications in bus-oriented systems. ■ Combines decoder and 3-bit address latch ■ Incorporates 3 enable inputs to simplify cascading ■ Low power dissipation: 28 mW typ ■ Switching specifications guaranteed over full temperature and VCC range ■ Advanced oxide-isolated, ion-implanted Schottky TTL process Ordering Code: Order Number Package Number Package Description DM74ALS137M M16A 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow DM74ALS137N 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 Function Table Inputs Enable Outputs Select GL G1 G2 C B A Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 X X H X X X H H H H H H H H X L X X X X H H H H H H H H L H L L L L L H H H H H H H L H L L L H H L H H H H H H L H L L H L H H L H H H H H L H L L H H H H H L H H H H L H L H L L H H H H L H H H L H L H L H H H H H H L H H L H L H H L H H H H H H L H H H H H H H H L L H L H H H H H L X X X Output corresponding to stored address, L; all others, H L = LOW State H = HIGH State X = Don't Care © 2000 Fairchild Semiconductor Corporation DS006202 www.fairchildsemi.com DM74ALS137 3 to 8 Line Decoder/Demultiplexer with Address Latches February 1991 DM74ALS137 Logic Diagram www.fairchildsemi.com 2 Supply Voltage 7V Input Voltage 7V 0°C to +70°C Operating Free Air Temperature Range 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. −65°C to +150°C Storage Temperature Range Typical θJA N Package 75.5°C/W M Package 104.0°C/W Recommended Operating Conditions Symbol Parameter Min Nom 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 −0.4 mA IOL LOW Level Output Current 8 mA tW Width of Enabling Pulse GL LOW 10 ns tSU Setup Time (Note 2) A, B, C 10↑ ns tH Hold Time (Note 2) A, B, C 5↑ TA Free Air Operating Temperature 2 V ns 0 °C 70 Note 2: The arrow (↑) indicates the positive edge of the GL input pulse is used for reference. Electrical Characteristics over recommended operating free air temperature range. All typical values are measured at VCC = 5V, TA = 25°C. Symbol Parameter Conditions VIK Input Clamp Voltage VCC = 4.5V, II = −18 mA VOH HIGH Level IOH = −0.4 mA Output Voltage VCC = 4.5V to 5.5V LOW Level VCC = 4.5V VOL Min Typ Max Units −1.5 V VCC − 2 Output Voltage V IOL = 4 mA 0.25 0.4 IOL = 8 mA 0.35 0.5 II Input Current @ Maximum VCC = 5.5V Enable 0.1 Input Voltage VIH = 7V A, B, C 0.1 IIH HIGH Level VCC = 5.5V Enable 20 Input Current VIH = 2.7V A, B, C 20 IIL LOW Level VCC = 5.5V Enable −0.1 Input Current VIL = 0.4V A, B, C −0.1 IO Output Drive Current VCC = 5.5V, VO = 2.25V ICC Supply Current VCC = 5.5V −30 5 3 V V mA µA mA −112 mA 11 mA www.fairchildsemi.com DM74ALS137 Absolute Maximum Ratings(Note 1) DM74ALS137 Switching Characteristics over recommended operating free air temperature range. Symbol tPLH tPHL Parameter Conditions tPHL tPLH tPHL tPLH tPHL To (Output) Propagation Delay Time VCC = 4.5V to 5.5V LOW-to-HIGH Level Output RL = 500Ω to Y Propagation Delay Time CL = 50 pF A, B, C Max Units 5 20 ns 6 20 ns 4 12 ns 5 15 ns 5 17 ns 5 15 ns 7 22 ns 7 20 ns to Y Propagation Delay Time G2 LOW-to-HIGH Level Output to Y Propagation Delay Time G2 HIGH-to-LOW Level Output to Y Propagation Delay Time G1 LOW-to-HIGH Level Output to Y Propagation Delay Time G1 HIGH-to-LOW Level Output to Y Propagation Delay Time GL LOW-to-HIGH Level Output to Y Propagation Delay Time GL HIGH-to-LOW Level Output to Y www.fairchildsemi.com Min A, B, C HIGH-to-LOW Level Output tPLH From (Input) 4 DM74ALS137 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 DM74ALS137 3 to 8 Line Decoder/Demultiplexer with Address Latches 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