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74HC/HCT646

Selection guide

Datasheet

74HC/HCT646
(Product Specification)
01-Sep-93, 12 pages, 88 kB

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74HC/HCT646 - Octal bus transceiver/register; 3-state

General description
Features
Products/packages
Quality/reliability/chemical content
Pricing/ordering/availability
Samples
Discontinued information
Applications
Block diagrams/pinning
Design support
Parametrics/similar products
Print/email
Disclaimers
All information hereunder is subject to the subsequent disclaimers

General description

The 74HC/HCT646 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC standard no. 7A.

The 74HC/HCT646 consist of bus transceiver circuits with 3-state outputs, D-type flip-flops, and control circuitry arranged for multiplexed transmission of data directly from the internal registers. Data on the 'A' or 'B' bus will be clocked into the registers as the appropriate clock (CPAB and CPBA) goes to a HIGH logic level. Output enable (OE) and direction (DIR) inputs are provided to control the transceiver function. In the transceiver mode, data present at the high-impedance port may be stored in either the 'A' or 'B' register, or in both. The select source inputs (SAB and SBA) can multiplex stored and real-time (transparent mode) data. The direction (DIR) input determines which bus will receive data when OE is active (LOW). In the isolation mode (OE = HIGH), 'A' data may be stored in the 'B' register and/or 'B' data may be stored in the 'A' register.
When an output function is disabled, the input function is still enabled and may be used to store and transmit data. Only one of the two buses, A or B, may be driven at a time.

The '646' is functionally identical to the '648', but has non-inverting data paths.

Features

  • Independent register for A and B buses
  • Multiplexed real-time and stored data
  • Output capability: bus driver
  • ICC category: MSI

Products/packages

Type numberOrderable part numberOrdering code (12NC)Product statusPackagePackingMarkingECCN
74HC646D74HC646D,6529337 155 30652Volume productionSOT137Bulk Pack, CECCStandard Marking
74HC646D74HC646D,6539337 155 30653Volume productionSOT137Reel Pack, SMD, 13", CECCStandard Marking
74HC646DB74HC646DB,1129351 894 20112Volume productionSOT340-1
(SSOP24)
TubeStandard Marking
74HC646DB74HC646DB,1189351 894 20118Volume productionSOT340-1
(SSOP24)
Reel Pack, SMD, 13"Standard Marking
74HC646N74HC646N,6529336 707 40652Volume productionSOT101-1
(DIP24)
Bulk Pack, CECCStandard Marking
74HCT646D74HCT646D,6529337 156 40652Volume productionSOT137Bulk Pack, CECCStandard Marking
74HCT646D74HCT646D,6539337 156 40653Volume productionSOT137Reel Pack, SMD, 13", CECCStandard Marking
74HCT646DB74HCT646DB,1129351 902 10112Volume productionSOT340-1
(SSOP24)
TubeStandard Marking
74HCT646DB74HCT646DB,1189351 902 10118Volume productionSOT340-1
(SSOP24)
Reel Pack, SMD, 13"Standard Marking
74HCT646N74HCT646N,6529336 709 90652Volume productionSOT101-1
(DIP24)
Bulk Pack, CECCStandard Marking

Quality/reliability/chemical content

Type numberOrderable part numberChemical contentRoHSLeadfree Conversion dateRHFIRF (FIT)MTBF (hours)MSL
74HC646D74HC646D,65274HC646D
week 6, 2005 6,621,51E+081
74HC646D74HC646D,65374HC646D
week 6, 2005 6,621,51E+081
74HC646DB74HC646DB,11274HC646DB
week 12, 2005 6,621,51E+081
74HC646DB74HC646DB,11874HC646DB
week 12, 2005 6,621,51E+081
74HC646N74HC646N,65274HC646N
Always Pb-free 6,621,51E+08NA
74HCT646D74HCT646D,65274HCT646D
week 6, 2005 6,621,51E+081
74HCT646D74HCT646D,65374HCT646D
week 6, 2005 6,621,51E+081
74HCT646DB74HCT646DB,11274HCT646DB
week 12, 2005 6,621,51E+081
74HCT646DB74HCT646DB,11874HCT646DB
week 12, 2005 6,621,51E+081
74HCT646N74HCT646N,65274HCT646N
Always Pb-free 6,621,51E+08NA

Quality and reliability disclaimer

Pricing/ordering/availability

Type numberOrdering code(12NC)Orderable part numberIndicative price/unit($)RegionDistributorIn stockOrder quantityInventory dateBuy onlineSamples
74HC646D9337 155 30652  74HC646D,652  1.1500NAFUTURE ELECTRONICS1,200 11/19/2009Buy onlinenot available
74HC646D9337 155 30653  74HC646D,653  1.1500      not available
74HC646DB9351 894 20112  74HC646DB,112  1.1500NADIGI-KEY CORPORATION765 11/20/2009Buy onlinenot available
74HC646DB9351 894 20118  74HC646DB,118  1.1500      not available
74HC646N9336 707 40652  74HC646N,652  1.2600NAFUTURE ELECTRONICS10,560 11/19/2009Buy onlinenot available
74HCT646D9337 156 40652  74HCT646D,652  1.1500      not available
74HCT646D9337 156 40653  74HCT646D,653  1.1500      not available
74HCT646DB9351 902 10112  74HCT646DB,112  1.1500NADIGI-KEY CORPORATION771 11/20/2009Buy onlinenot available
74HCT646DB9351 902 10118  74HCT646DB,118  1.1500      not available
74HCT646N9336 709 90652  74HCT646N,652  1.2600      not available

Applications

  • Bus interfaces.

Design support

Support Documents

Parametrics/similar products

Type numberPackageDescriptionFmax(MHz)Propagation Delay(ns)VoltageNo. of PinsPower Dissipation ConsiderationsLogic Switching LevelsOutput Drive Capability
74HC646DSOT137
Transceiver/Register (3-State)75 @ 6 V11@5V2.0-6.0 V24Low Power or Battery ApplicationsCMOS+/- 7.8 mA
74HC646DBSOT340-1
(SSOP24)
Transceiver/Register (3-State)75 @ 6 V11@5V2.0-6.0 V24Low Power or Battery ApplicationsCMOS+/- 7.8 mA
74HC646NSOT101-1
(DIP24)
Transceiver/Register (3-State)75 @ 6 V11@5V2.0-6.0 V24Low Power or Battery ApplicationsCMOS+/- 7.8 mA
74HCT646DSOT137
Transceiver/Register; TTL Enabled (3-State)85134.5-5.5 V24Low PowerTTL+/- 6 mA
74HCT646DBSOT340-1
(SSOP24)
Transceiver/Register; TTL Enabled (3-State)85134.5-5.5 V24Low PowerTTL+/- 6 mA
74HCT646NSOT101-1
(DIP24)
Transceiver/Register; TTL Enabled (3-State)85134.5-5.5 V24Low PowerTTL+/- 6 mA


Similar products
74HC/HCT646 links to the similar products page containing an overview of products that are similar in function or related to the type number(s) as listed on this page. The similar products page includes products from the same catalog tree(s), relevant selection guides and products from the same functional category.