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54LS257

54LS257

  • 厂商:

    NSC

  • 封装:

  • 描述:

    54LS257 - TRI-STATE Quad 2-Data Selectors/Multiplexers - National Semiconductor

  • 数据手册
  • 价格&库存
54LS257 数据手册
54LS257A DM54LS257B DM74LS257B 54LS258A DM54LS258B DM74LS258B TRI-STATE Quad 2-Data Selectors Multiplexers June 1989 54LS257A DM54LS257B DM74LS257B 54LS258A DM54LS258B DM74LS258B TRI-STATE Quad 2-Data Selectors Multiplexers General Description These Schottky-clamped high-performance multiplexers feature TRI-STATE outputs that can interface directly with data lines of bus-organized systems With all but one of the common outputs disabled (at a high impedance state) the low impedance of the single enabled output will drive the bus line to a high or low logic level To minimize the possibility that two outputs will attempt to take a common bus to opposite logic levels the output enable circuitry is designed such that the output disable times are shorter than the output enable times This TRI-STATE output feature means that n-bit (paralleled) data selectors with up to 258 sources can be implemented for data buses It also permits the use of standard TTL registers for data retention throughout the system Features Y Y Y Y Y Y TRI-STATE versions LS157 and LS158 with same pinouts Schottky-clamped for significant improvement in A-C performance Provides bus interface from multiple sources in highperformance systems Average propagation delay from data input 12 ns Typical power dissipation LS257B 50 mW LS258B 35 mW Alternate military aerospace devices (54LS257A 54LS258A) are available Contact a National Semiconductor Sales Office Distributor for specifications Connection Diagrams Dual-In-Line Package Dual-In-Line Package TL F 6417 – 1 TL F 6417 – 2 Order Number 54LS257ADMQB 54LS257AFMQB 54LS257ALMQB DM54LS257BJ DM54LS257BW DM74LS257BM or DM74LS257BN See NS Package Number E20A J16A M16A N16E or W16A Order Number 54LS258ADMQB 54LS258AFMQB 54LS258ALMQB DM54LS258BJ DM54LS258BW DM74LS258BM or DM74LS258BN See NS Package Number E20A J16A M16A N16E or W16A Function Table Inputs Output Control H L L L L Select X L L H H A X L H X X B X X X L H Output Y LS257 Z L H L H LS258 Z H L H L H e High Level L e Low Level X e Don’t Care Z e High Impedance (off) TRI-STATE is a registered trademark of National Semiconductor Corporation C1995 National Semiconductor Corporation TL F 6417 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 b 55 C to a 125 C DM54LS and 54LS DM74LS 0 C to a 70 C Storage Temperature Range b 65 C to a 150 C 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 Recommended Operating Conditions Symbol VCC VIH VIL IOH IOL TA Parameter Min Supply Voltage High Level Input Voltage Low Level Input Voltage High Level Output Current Low Level Output Current Free Air Operating Temperature b 55 DM54LS257B Nom 5 Max 55 07 b1 DM74LS257B Min 4 75 2 08 b2 6 Units Max 5 25 V V V mA mA C Nom 5 45 2 12 125 0 24 70 ’LS257B Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted) Symbol VI VOH VOL Parameter Input Clamp Voltage High Level Output Voltage Low Level Output Voltage Conditions VCC e Min II e b18 mA VCC e Min IOH e Max VIL e Max VIH e Min VCC e Min IOL e Max VIL e Max VIH e Min IOL e 12 mA VCC e Min II IIH IIL IOZH Input Current Input Voltage Max VCC e Max VI e 7V VCC e Max VI e 2 7V VCC e Max VI e 0 4V VCC e Max VO e 2 7V VIH e Min VIL e Max VCC e Max VO e 0 4V VIH e Min VIL e Max VCC e Max (Note 2) VCC e Max (Note 3) VCC e Max (Note 3) VCC e Max (Note 3) DM54 DM74 b 20 b 20 Min Typ (Note 1) 34 31 0 25 0 35 0 25 Max b1 5 Units V V DM54 DM74 DM54 DM74 DM74 Select Other Select Other Select Other 24 24 04 05 04 02 01 40 20 b0 8 b0 4 V mA mA mA High Level Input Current Low Level Input Current Off-State Output Current with High Level Output Voltage Applied Off-State Output Current with Low Level Output Voltage Applied Short Circuit Output Current Supply Current with Outputs High Supply Current with Outputs Low Supply Current with Outputs Disabled 20 mA IOZL b 20 b 100 b 100 mA IOS ICCH ICCL ICCZ mA mA mA mA 59 92 12 10 16 19 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 Note 3 ICC is measured with all outputs open and all possible inputs grounded while achieving the stated output conditions 2 ’LS257B Switching Characteristics at VCC e 5V and TA e 25 C (See Section 1 for Test Waveforms and Output Load) From (Input) To (Output) RL e 667X CL e 45 pF Min tPLH tPHL tPLH tPHL tPZH tPZL tPHZ tPLZ Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Output Enable Time to High Level Output Output Enable Time to Low Level Output Output Disable Time from High Level Output (Note 1) Output Disable Time from Low Level Output (Note 1) Data to Output Data to Output Select to Output Select to Output Output Control to Y Output Control to Y Output Control to Y Output Control to Y Max 18 18 28 35 15 28 26 25 CL e 150 pF Min Max 27 27 35 42 27 38 ns ns ns ns ns ns ns ns Units Symbol Parameter Note 1 CL e 5 pF Recommended Operating Conditions Symbol VCC VIH VIL IOH IOL TA Parameter Min Supply Voltage High Level Input Voltage Low Level Input Voltage High Level Output Current Low Level Output Current Free Air Operating Temperature b 55 DM54LS258B Nom 5 Max 55 Min 4 75 2 07 b1 DM74LS258B Nom 5 Max 5 25 Units V V 08 b2 6 45 2 V mA mA C 12 125 0 24 70 ’LS258B Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted) Symbol VI VOH Parameter Input Clamp Voltage High Level Output Voltage Low Level Output Voltage Conditions VCC e Min II e b18 mA VCC e Min IOH e Max VIL e Max VIH e Min VCC e Min IOL e Max VIL e Max VIH e Min IOL e 12 mA VCC e Min II Input Current Input Voltage Max VCC e Max VI e 7V VCC e Max VI e 2 7V DM54 DM74 DM54 DM74 DM74 Select Other Select Other 24 24 34 31 0 25 0 35 0 25 04 05 04 02 01 40 20 mA mA V Min Typ (Note 1) Max b1 5 Units V V VOL IIH High Level Input Current 3 ’LS258B Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted) (Continued) Symbol IIL Parameter Low Level Input Current Off-State Output Current with High Level Output Voltage Applied Off-State Output Current with Low Level Output Voltage Applied Short Circuit Output Current Supply Current with Outputs High Supply Current with Outputs Low Supply Current with Outputs Disabled VCC e Max VI e 0 4V VCC e Max VO e 2 7V VIH e Min VIL e Max VCC e Max VO e 0 4V VIH e Min VIL e Max VCC e Max (Note 2) VCC e Max (Note 3) VCC e Max (Note 3) VCC e Max (Note 3) DM54 DM74 b 20 b 20 Conditions Select Other Min Typ (Note 1) Max b0 8 b0 4 Units mA IOZH 20 mA IOZL b 20 b 100 b 100 mA IOS mA ICCH ICCL ICCZ 41 9 12 7 14 19 mA mA mA 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 Note 3 ICC is measured with all outputs open and all possible inputs grounded while achieving the stated output conditions ’LS258B Switching Characteristics at VCC e 5V and TA e 25 C (See Section 1 for Test Waveforms and Output Load) From (Input) To (Output) RL e 667X CL e 45 pF Min tPLH tPHL tPLH tPHL tPZH tPZL tPHZ tPLZ Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Output Enable Time to High Level Output Output Enable Time to Low Level Output Output Disable Time from High Level Output (Note 4) Output Disable Time from Low Level Output (Note 4) Data to Output Data to Output Select to Output Select to Output Output Control to Y Output Control to Y Output Control to Y Output Control to Y Max 18 18 28 35 15 28 26 25 CL e 150 pF Min Max 27 27 35 42 27 38 ns ns ns ns ns ns ns ns Units Symbol Parameter Note 4 CL e 5 pF 4 Logic Diagrams LS257B TL F 6417 – 3 LS258B TL F 6417 – 4 5 Physical Dimensions inches (millimeters) Ceramic Leadless Chip Carrier Package (E) Order Number 54LS257ALMQB or 54LS258ALMQB NS Package Number E20A 16-Lead Ceramic Dual-In-Line Package (J) Order Number 54LS257ADMQB 54LS258ADMQB DM54LS257BJ or DM54LS258BJ NS Package Number J16A 6 Physical Dimensions inches (millimeters) (Continued) 16-Lead Small Outline Molded Package (M) Order Number DM74LS257BM or DM74LS258BM NS Package Number M16A 16-Lead Molded Dual-In-Line Package (N) Order Number DM74LS257BN or DM74LS258BN NS Package Number N16E 7 54LS257A DM54LS257B DM74LS257B 54LS258A DM54LS258B DM74LS258B TRI-STATE Quad 2-Data Selectors Multiplexers Physical Dimensions inches (millimeters) (Continued) 16-Lead Ceramic Flat Package (W) Order Number 54LS257AFMQB or 54LS258AFMQB NS Package Number W16A 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 systems which (a) are intended for surgical implant into the body or (b) support or sustain life and 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 National Semiconductor Corporation 1111 West Bardin Road Arlington TX 76017 Tel 1(800) 272-9959 Fax 1(800) 737-7018 2 A critical component is 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 National Semiconductor Europe Fax (a49) 0-180-530 85 86 Email cnjwge tevm2 nsc com Deutsch Tel (a49) 0-180-530 85 85 English Tel (a49) 0-180-532 78 32 Fran ais Tel (a49) 0-180-532 93 58 Italiano Tel (a49) 0-180-534 16 80 National Semiconductor Hong Kong Ltd 13th Floor Straight Block Ocean Centre 5 Canton Rd Tsimshatsui Kowloon Hong Kong Tel (852) 2737-1600 Fax (852) 2736-9960 National Semiconductor Japan Ltd Tel 81-043-299-2309 Fax 81-043-299-2408 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
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