Please enter a valid full or partial manufacturer part number with a minimum of 3 letters or numbers

    SN74HC646 Search Results

    SN74HC646 Result Highlights (2)

    Part ECAD Model Manufacturer Description Download Buy
    SN74HC646DW Texas Instruments Octal Bus Transceivers And Registers With 3-State Outputs 24-SOIC -40 to 85 Visit Texas Instruments Buy
    SN74HC646DWR Texas Instruments Octal Bus Transceivers And Registers With 3-State Outputs 24-SOIC -40 to 85 Visit Texas Instruments Buy
    SF Impression Pixel

    SN74HC646 Price and Stock

    Texas Instruments SN74HC646DWR

    IC TXRX NON-INVERT 6V 24SOIC
    Distributors Part Package Stock Lead Time Min Order Qty Price Buy
    DigiKey SN74HC646DWR Cut Tape 2,723 1
    • 1 $1.37
    • 10 $0.996
    • 100 $0.7999
    • 1000 $0.6972
    • 10000 $0.6972
    Buy Now
    SN74HC646DWR Digi-Reel 2,723 1
    • 1 $1.37
    • 10 $0.996
    • 100 $0.7999
    • 1000 $0.6972
    • 10000 $0.6972
    Buy Now
    SN74HC646DWR Reel 2,000
    • 1 -
    • 10 -
    • 100 -
    • 1000 -
    • 10000 $0.64342
    Buy Now
    Mouser Electronics SN74HC646DWR 1,520
    • 1 $1.37
    • 10 $0.903
    • 100 $0.751
    • 1000 $0.698
    • 10000 $0.662
    Buy Now
    Rochester Electronics SN74HC646DWR 16,000 1
    • 1 $0.7653
    • 10 $0.7653
    • 100 $0.7194
    • 1000 $0.6505
    • 10000 $0.6505
    Buy Now

    Texas Instruments SN74HC646DW

    IC TXRX NON-INVERT 6V 24SOIC
    Distributors Part Package Stock Lead Time Min Order Qty Price Buy
    DigiKey SN74HC646DW Tube 1,313 1
    • 1 $1.79
    • 10 $1.312
    • 100 $1.0633
    • 1000 $0.93275
    • 10000 $0.93275
    Buy Now
    Quest Components SN74HC646DW 80
    • 1 $4
    • 10 $4
    • 100 $2
    • 1000 $2
    • 10000 $2
    Buy Now
    SN74HC646DW 40
    • 1 $3.2
    • 10 $3.2
    • 100 $1.76
    • 1000 $1.76
    • 10000 $1.76
    Buy Now
    SN74HC646DW 25
    • 1 $1.504
    • 10 $1.3837
    • 100 $1.2032
    • 1000 $1.2032
    • 10000 $1.2032
    Buy Now
    Rochester Electronics SN74HC646DW 3,596 1
    • 1 $0.8986
    • 10 $0.8986
    • 100 $0.8447
    • 1000 $0.7638
    • 10000 $0.7638
    Buy Now
    Ameya Holding Limited SN74HC646DW 15,575
    • 1 -
    • 10 -
    • 100 -
    • 1000 -
    • 10000 -
    Get Quote

    Rochester Electronics LLC SN74HC646DW

    SN74HC646 OCTAL BUS TRANSCEIVERS
    Distributors Part Package Stock Lead Time Min Order Qty Price Buy
    DigiKey SN74HC646DW Bulk 322
    • 1 -
    • 10 -
    • 100 -
    • 1000 $0.93
    • 10000 $0.93
    Buy Now

    Texas Instruments SN74HC646NT

    IC TXRX NON-INVERT 6V 24DIP
    Distributors Part Package Stock Lead Time Min Order Qty Price Buy
    DigiKey SN74HC646NT Tube
    • 1 -
    • 10 -
    • 100 -
    • 1000 -
    • 10000 -
    Buy Now
    Bristol Electronics SN74HC646NT 25
    • 1 -
    • 10 -
    • 100 -
    • 1000 -
    • 10000 -
    Get Quote
    Quest Components SN74HC646NT 122
    • 1 $3.156
    • 10 $3.156
    • 100 $2.104
    • 1000 $1.9462
    • 10000 $1.9462
    Buy Now
    Ameya Holding Limited SN74HC646NT 1,255
    • 1 -
    • 10 -
    • 100 -
    • 1000 -
    • 10000 -
    Get Quote
    ComSIT USA SN74HC646NT 12
    • 1 -
    • 10 -
    • 100 -
    • 1000 -
    • 10000 -
    Get Quote

    Rochester Electronics LLC SN74HC646DWR

    SN74HC646 OCTAL BUS TRANSCEIVERS
    Distributors Part Package Stock Lead Time Min Order Qty Price Buy
    DigiKey SN74HC646DWR Bulk 434
    • 1 -
    • 10 -
    • 100 -
    • 1000 $0.69
    • 10000 $0.69
    Buy Now

    SN74HC646 Datasheets (38)

    Part ECAD Model Manufacturer Description Curated Datasheet Type PDF
    SN74HC646 Texas Instruments Octal Bus Transceivers And Registers With 3-State Outputs Original PDF
    SN74HC646 Texas Instruments OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS Original PDF
    SN74HC646DW Texas Instruments Logic - Buffers, Drivers, Receivers, Transceivers, Integrated Circuits (ICs), IC BUS TRANSCEIVER 8BIT 24SOIC Original PDF
    SN74HC646DW Texas Instruments OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS Original PDF
    SN74HC646DW Texas Instruments Octal Bus Transceivers And Registers With 3-State Outputs 24-SOIC -40 to 85 Original PDF
    SN74HC646DW Texas Instruments Octal Bus Transceiver and Register with 3-State Outputs Original PDF
    SN74HC646DW Unknown Historical semiconductor price guide (US$ - 1998). From our catalog scanning project. Historical PDF
    SN74HC646DW Texas Instruments OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS Scan PDF
    SN74HC646DW-00 Texas Instruments SN74HC646 - IC HC/UH SERIES, 8-BIT REGISTERED TRANSCEIVER, TRUE OUTPUT, PDSO24, Bus Driver/Transceiver Original PDF
    SN74HC646DWE4 Texas Instruments Logic - Buffers, Drivers, Receivers, Transceivers, Integrated Circuits (ICs), IC BUS TRANSCEIVER 8BIT 24SOIC Original PDF
    SN74HC646DWE4 Texas Instruments Octal Bus Transceivers And Registers With 3-State Outputs 24-SOIC -40 to 85 Original PDF
    SN74HC646DWE4 Texas Instruments Octal Bus Transceivers And Registers With 3-State Outputs Original PDF
    SN74HC646DWG4 Texas Instruments Logic - Buffers, Drivers, Receivers, Transceivers, Integrated Circuits (ICs), IC BUS TRANSCEIVER 8BIT 24SOIC Original PDF
    SN74HC646DWG4 Texas Instruments Octal Bus Transceivers And Registers With 3-State Outputs 24-SOIC -40 to 85 Original PDF
    SN74HC646DWR Texas Instruments Octal Bus Transceivers And Registers With 3-State Outputs 24-SOIC -40 to 85 Original PDF
    SN74HC646DWR Texas Instruments OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS Original PDF
    SN74HC646DWR Texas Instruments Octal Bus Transceiver and Register with 3-State Outputs Original PDF
    SN74HC646DWR Texas Instruments Logic - Buffers, Drivers, Receivers, Transceivers, Integrated Circuits (ICs), IC BUS TRANSCEIVER 8BIT 24SOIC Original PDF
    SN74HC646DWR-00 Texas Instruments SN74HC646 - IC HC/UH SERIES, 8-BIT REGISTERED TRANSCEIVER, TRUE OUTPUT, PDSO24, Bus Driver/Transceiver Original PDF
    SN74HC646DWRE4 Texas Instruments Octal Bus Transceivers And Registers With 3-State Outputs 24-SOIC -40 to 85 Original PDF

    SN74HC646 Datasheets Context Search

    Catalog Datasheet MFG & Type Document Tags PDF

    HC646

    Abstract: SN54HC646 SN74HC646
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150B – DECEMBER 1982 – REVISED MAY 1997 D Independent Registers for A and B Buses Multiplexed Real-Time and Stored Data True Data Paths High-Current 3-State Outputs Can Drive up


    Original
    SN54HC646, SN74HC646 SCLS150B 300-mil SN54HC646 HC646 SN54HC646 SN74HC646 PDF

    HC646

    Abstract: SN54HC646 SN74HC646
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150A – DECEMBER 1982 – REVISED JANUARY 1996 D D D D Independent Registers for A and B Buses Multiplexed Real-Time and Stored Data True Data Paths High-Current 3-State Outputs Can Drive


    Original
    SN54HC646, SN74HC646 SCLS150A 300-mil SN54HC646 HC646 SN54HC646 SN74HC646 PDF

    Untitled

    Abstract: No abstract text available
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 PDF

    Untitled

    Abstract: No abstract text available
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 PDF

    HC646

    Abstract: SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 HC646 SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W PDF

    HC646

    Abstract: SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 HC646 SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W PDF

    HC646

    Abstract: SN54HC646 SN74HC646
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150B – DECEMBER 1982 – REVISED MAY 1997 D Independent Registers for A and B Buses Multiplexed Real-Time and Stored Data True Data Paths High-Current 3-State Outputs Can Drive up


    Original
    SN54HC646, SN74HC646 SCLS150B 300-mil SN54HC646 HC646 SN54HC646 SN74HC646 PDF

    HC646

    Abstract: SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 HC646 SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W PDF

    HC646

    Abstract: SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 HC646 SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W PDF

    HC646

    Abstract: SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 HC646 SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W PDF

    HC646

    Abstract: SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 HC646 SN54HC646 SN74HC646 SN74HC646DW SN74HC646DWR SN74HC646NT SNJ54HC646FK SNJ54HC646JT SNJ54HC646W PDF

    Untitled

    Abstract: No abstract text available
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 SN74HC646 PDF

    Untitled

    Abstract: No abstract text available
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 SN74HC646 PDF

    Untitled

    Abstract: No abstract text available
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 PDF

    Untitled

    Abstract: No abstract text available
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS SCLS150C – DECEMBER 1982 – REVISED MARCH 2003 D D D D D D D Wide Operating Voltage Range of 2 V to 6 V High-Current 3-State Outputs Can Drive Up To 15 LSTTL Loads Low Power Consumption, 80-µA Max ICC


    Original
    SN54HC646, SN74HC646 SCLS150C SN54HC646 SN74HC646 PDF

    5555 FAIRCHILD optocoupler

    Abstract: MC74HC374N 74hc14n equivalent NC7S125M5 14069 HCF4541BEY APPLICATION HCF4013BE 4026 fairchild datasheet 14543 motorola Motorola DM74LS139N
    Text: R E L I A B L E . L O G I C . I N N O V A T I O N . Logic Cross-Reference Logic Cross-Reference 2003 Texas Instruments Printed in the U.S.A. by Texoma Business Forms, Durant, Oklahoma Printed on recycled paper. SCYB017A NEW First Revision Logic Cross-Reference


    Original
    SCYB017A A010203 5555 FAIRCHILD optocoupler MC74HC374N 74hc14n equivalent NC7S125M5 14069 HCF4541BEY APPLICATION HCF4013BE 4026 fairchild datasheet 14543 motorola Motorola DM74LS139N PDF

    hct 4047 bt

    Abstract: SN74ALS679 FCT Fast CMOS TTL Logic 74LS 4075 7804 inverter SN74368A DTL Logic 4069 CMOS hex inverter SN502 CD74AC374
    Text: IMPORTANT NOTICE Texas Instruments and its subsidiaries TI reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold


    Original
    SDYZ001A, SN74LS138D SN74LS138DR SN74LS138N SN74LS138N3 SN74LS138NSR images/sn74ls138 hct 4047 bt SN74ALS679 FCT Fast CMOS TTL Logic 74LS 4075 7804 inverter SN74368A DTL Logic 4069 CMOS hex inverter SN502 CD74AC374 PDF

    HC646

    Abstract: J1112 SN54HC646 SN74HC646 IC 370
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS S C L S 1 5 0 A - D E C EM BE R 1982 - R EVISED JA N U A R Y 1996 Independent Registers for A and B Buses Multiplexed Real-Time and Stored Data True Data Paths SN54HC646 . . . JT OR W PACKAGE


    OCR Scan
    SN54HC646, SN74HC646 SCLS150A- 300-mil SN54HC646 HC646 J1112 SN54HC646 SN74HC646 IC 370 PDF

    SN74HC846

    Abstract: 54HC646
    Text: SN54HC646, SN54HC648, SN74HC646, SN74HC648 OC TAL BUS TRANSCEIVERS AN D REGISTERS WITH 3-STATE OUTPUTS D 2 8 8 4 , DECEMBER 1 9 8 2 —REVISED SEPTEMBER 1 9 8 7 • Independent Registers for A and B Buses • Multiplexed Real-Time and Stored Data • Choice of True or Inverting Data Paths


    OCR Scan
    SN54HC646, SN54HC648, SN74HC646, SN74HC648 300-mil SN54HC N74HC646 SN74HC846 54HC646 PDF

    P9024

    Abstract: 54HC646
    Text: SN54HC646, SN54HC648, SN74HC646, SN74HC648 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3 STATE OUTPUTS D2684, DECEMBER 1982-REVISED SEPTEMBER 1987 • Independent Registers lor A and B Buses • Multiplexed Real-Time and Stored Data • Choice of True or Inverting Data Paths


    OCR Scan
    SN54HC646, SN54HC648, SN74HC646, SN74HC648 D2684, 1982-REVISED SN54H SN74H P9024 54HC646 PDF

    Untitled

    Abstract: No abstract text available
    Text: SN54HC646, SN74HC646 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS _ SCLS1 SPA - DECEMBER 1982 - REVISED JANUARY 1996 • • • • Independent Registers for A and B Buses Multiplexed Real-Time and Stored Data S N 5 4H C 64 6. . . JT O R W


    OCR Scan
    SN54HC646, SN74HC646 300-mll PDF

    Untitled

    Abstract: No abstract text available
    Text: TEXAS INSTR LOGIC BSE ]> • 6 U 17 2-3 ODfibfl'it. S ■ SN54HC646, SN54HC648, SN74HC646, SN74HC648 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS □2684, DECEMBER 1982-REV1SED SEPTEMBER 1987 S N 5 4 H C ' . . . J T PACKAGE S N 7 4 H C ' . . . D W or NT P A CK A GE


    OCR Scan
    SN54HC646, SN54HC648, SN74HC646, SN74HC648 1982-REV1SED 300-mil SN74HC646 PDF

    HC646

    Abstract: HC648 SN54HC646 SN74HC SN74HC646 SN74HC648 SN54HC648
    Text: SN54HC646, SN54HC648, SN74HC646, SN74HC648 OCTAL BUS TRANSCEIVERS AND REGISTERS WITH 3-STATE OUTPUTS □ 2 6 8 4 , DECEMBER 1 9 8 2 -R E V IS E D SEPTEMBER 1 9 8 7 S N 5 4 H C ' . . . J T P AC KA G E S N 7 4 H C '. . . D W o r N T PAC KA G E Independent Registers fo r A and B Buses


    OCR Scan
    SN54HC646, SN54HC648, SN74HC646, SN74HC648 1982-REVISED 300-mil HC646 HC648 SN54HC646 SN74HC SN74HC646 SN54HC648 PDF

    PC74HC04

    Abstract: PC74HC154 PC74HC191 PC74HCT541 PC74HCT245 MC74HC266 PC74HC374 PC74HCT244 PC74HCT86 PC74HC273
    Text: CROSS REFERENCE TABLE TOSHIBA TC74HC00A MOTOROLA MC74HC00 T1 SN74HCOO TC74HCT00A TC74HC02A MC74HC02 SN74HC02 TC74HCT02A HARRIS S1GNET1CS NATIONAL Ì SEMICONDUCTOR CD74HC00 PC74HCOO MM74HC00 CD74HCT00 PC74HCTOO MM74HCTOO MM74HC02 CD74IIC02 PC74HC02 CD74HCT02


    OCR Scan
    TC74HC00A TC74HCT00A TC74HC02A TC74HCT02A TC74HC03A TC74HC04A TC74HCU04A TC74HCT04A TC74HC05A TC74HC07A PC74HC04 PC74HC154 PC74HC191 PC74HCT541 PC74HCT245 MC74HC266 PC74HC374 PC74HCT244 PC74HCT86 PC74HC273 PDF