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2 Answers

  • Anonymous
    2 decades ago
    Favorite Answer

    74xx standard (標準TTL) 優點 : 平

    delay time : 10nS

    功率消耗 : 10mW

    電源: 5V

    74LSxx(省電、TTL) 優點 : 省電

    delay time : 8nS

    功率消耗 : 2mW

    電源: 5V

    "L"指 LOW POWER;"S"指 Schottky(是一種加速技術)

    74ASxx(超快、TTL) 優點 : 快(工作頻率達100MHz以上)

    delay time : 1.5nS

    功率消耗 : 4mW

    電源: 5V

    "A"指 Advanced(增進);"S"指 Schottky(是一種加速技術)


    優點 : 快(工作頻率達100MHz以上)

    delay time : 3nS

    功率消耗 : 4mW

    電源: 5V

    "F"指 fast;是 National Semiconductor 所開發的另一種技術

    74HCxx 優點 : 省電

    缺點 : 慢;不適用於高頻;跟 74xx TTL 不相容

    delay time : 20nS

    功率消耗 : 1mW

    電源: 2-6V;(但與其它74xx series 一起用時要用5V)

    "H"指 High speed;"C"指 CMOS (是一種用於省電的技術)

    注意: 74HCxx 不 是"TTL"技術,因 74HCxx 是以 3.5V 以上為正,但 74xx TTL 的高輸出是 2.4V 以上,因而導致不相容。

    但以 74HCxx 作輸出給 74xx TTL 則沒有問題

    74HCTxx 優點 : 省電、能跟 74xx TTL 完全相容

    缺點 : 慢;不適用於高頻

    delay time : 40nS

    功率消耗 : 1mW

    電源: 2-6V;(但與其它74xx series 一起用時要用5V)

    "H"指 High speed; "C"指 CMOS (是一種用於省電的技術); "T" 指 TTL compatible(跟 74xx TTL 完全相容)

    74ACT(快) 優點 : 快(工作頻率達100MHz以上)、省電、能跟 74xx TTL 完全相容

    缺點 : 貴

    delay time : 5nS

    功率消耗 : 0.5mW

    電源: 2-6V;(但與其它74xx series 一起用時要用5V)

    "H"指 High speed; "C"指 CMOS (是一種用於省電的技術); "T" 指 TTL compatible(跟 74xx TTL 完全相容)


    2005-11-06 22:33:48 補充:

    Family Description

    74 True TTL

    74L Low power

    74S Schottky

    74H High speed

    74LS Low power - Schottky

    74AS Advanced - Schottky

    74ALS Advanced - Low power - Schottky

    74F(AST) Fast - (Advanced - Schottky)

    74C CMOS...................check Vcc levels

    2005-11-06 22:35:26 補充:

    74HC (U) High speed - CMOS (Unbuffered output)

    74HCT High speed - CMOS - TTL inputs

    74AHC Advanced - High speed - CMOS

    74AHCT Advanced - High speed - CMOS - TTL inputs

    74FCT (-A,-T,-AT) Fast - CMOS - TTL inputs (speed variations)

    2005-11-06 22:36:14 補充:

    74AC Advanced - CMOS

    74ACT Advanced - CMOS - TTL inputs

    74FACT AC, ACT (Q) series

    74ACQ Advanced - CMOS - Quiet outputs

    74ACTQ Advanced - CMOS - TTL inputs - Quiet outputs

    2005-11-06 22:36:52 補充:

    Bus Driver Families

    74ABT Advanced - BiCMOS - Technology

    74ABTE ABT - Enhanced Transceiver Logic

    74ABTH Advanced - BiCMOS - Technology - bus Hold

    2005-11-06 22:37:25 補充:

    74BCT BiCMOS - TTL inputs

    74BTL Backplane - Transceiver - Logic (BiCMOS)

    74FB Futurebus+

    74GTL Gunning - Transceiver - Logic

    74GTLP GTL - Plus

    2005-11-06 22:38:14 補充:

    Low Voltage Families

    74ALB Advanced - Low Voltage - BiCMOS

    74LV (U) Low - Voltage (Unbuffered output) (CMOS)

    74LVC (R) (U) LV - CMOS (damping Resistor)(Unbuffered output)

    74LVCH Low - Voltage - CMOS - bus Hold

    74ALVC Advanced - Low - Voltage - CMOS

    2005-11-06 22:39:02 補充:

    74LVT (R) (U) LV - TTL (damping Resistor)(Unbuffered output) (BiCMOS)

    74LVTZ Low - Voltage - TTL - High Impedance power-up

    74ALVC (R) ALV CMOS (bus Hold) (damping Resistor)

    2005-11-06 22:39:33 補充:

    74ALVCH Advanced - Low - Voltage - CMOS - bus Hold

    74LCX LV - CMOS (operates with 3v and 5v supplies)

    74VCX LV - CMOS (operates with 1.8v and 3.6v supplies)

  • 1 decade ago


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