SN74LS641-1DWG4 Texas Instruments Integrated Circuit (Small Outline Packages) In Stock

Texas Instruments SN74LS641-1DWG4 is an 8-channel bidirectional bus transceiver with open-collector outputs and common direction control. Features 24 mA output sink current in a 20-pin SOIC package. Available from stock worldwide with fast shipping.

OBSOLETEIntegrated CircuitVerified May 2026
Package / Visual Reference
SN74LS641-1DWG4Small Outline Packages
Quick Facts
Manufacturer
Texas Instruments
Package
Small Outline Packages
Pin Count
20
Lifecycle
OBSOLETE
Category
Integrated Circuit
Temp Range
?°C to 70.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

What are the key features of SN74LS641-1DWG4?

  • 8-channel bidirectional bus transceiver with open-collector outputs capable of sinking 24 mA, enabling wired-OR bus configurations
  • Common direction control pin selects A-to-B or B-to-A data flow across all 8 channels simultaneously for simplified bus management
  • 20-pin SOIC package from Texas Instruments LS logic family, compatible with 5 V TTL systems and legacy backplane designs

What is SN74LS641-1DWG4 used for?

The SN74LS641-1DWG4 is used in 8-bit backplane data bus interfaces, industrial process-control boards, and multi-board VME or ISA systems requiring bidirectional data transfer with wired-OR capability. Its open-collector outputs allow multiple transceivers to share a common bus without bus contention, which is essential in memory expansion and peripheral interface designs. The device fits well in retrofitting legacy TTL logic systems that need reliable 5 V bus buffering with directional control.

What are the specifications of SN74LS641-1DWG4?

YTEOL0
Additional FeatureWITH DIRECTION CONTROL
Control TypeCOMMON CONTROL
Count DirectionBIDIRECTIONAL
FamilyLS
JESD-30 CodeR-PDSO-G20
JESD-609 Codee4
Logic IC TypeBUS TRANSCEIVER
Max I(ol)0.024A
Number of Bits8
Number of Functions1
Number of Ports2
Output CharacteristicsOPEN-COLLECTOR
Output PolarityTRUE
Package Body MaterialPLASTIC/EPOXY
Package Equivalence CodeSOP20,.4
Package ShapeRECTANGULAR
Package StyleSMALL OUTLINE
Packing MethodTUBE
Peak Reflow Temperature (Cel)260
Power Supply Current-Max (ICC)95mA
Prop. Delay@Nom-Sup25ns
Propagation Delay (tpd)25ns
Qualification StatusNot Qualified
Supply Voltage-Max (Vsup)5.25V
Supply Voltage-Min (Vsup)4.75V
Supply Voltage-Nom (Vsup)5V
Surface MountYES
TechnologyTTL
Temperature GradeCOMMERCIAL
Terminal FinishNICKEL PALLADIUM GOLD
Terminal FormGULL WING
Terminal Pitch1.27mm
Terminal PositionDUAL
Time@Peak Reflow Temperature-Max (s)30
PackageSmall Outline Packages

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
Moisture Sensitivity LevelMSL 1
HTS Code8542.39.00.60

Where can I find the SN74LS641-1DWG4 datasheet?

SN74LS641-1DWG4 Datasheet Download

Official datasheet from Texas Instruments

What are equivalent replacements for SN74LS641-1DWG4?

Compatible alternatives and drop-in replacements for SN74LS641-1DWG4:

SN74LS641DWonsemi

Bus Transceiver, LS Series, 1-Func, 8-Bit, True Output, TTL, PDSO20

View Part →
SN74LS641NSFreescale Semiconductor

IC,BUS TRANSCEIVER,SINGLE,8-BIT,LS-TTL,DIP,20PIN,PLASTIC

View Part →
SN74LS641DWG4Texas Instruments

Bus Transceiver, LS Series, 1-Func, 8-Bit, True Output, TTL, PDSO20

View Part →
SN74LS642DWG4Texas Instruments

Bus Transceiver, LS Series, 1-Func, 8-Bit, Inverted Output, TTL, PDIP20

View Part →

Frequently Asked Questions

What output sink current does the SN74LS641-1DWG4 support and how does the open-collector output enable wired-OR bus sharing?

The SN74LS641-1DWG4 open-collector outputs sink up to 24 mA (I_OL maximum), allowing multiple devices to share a single bus line with a common pull-up resistor. When any output asserts logic low, the bus line is pulled low; when all outputs are high-impedance, the pull-up holds the line high. This wired-OR topology supports 8 channels of bidirectional data across devices without bus contention.

How does the direction control signal on SN74LS641-1DWG4 work for a CPU-to-memory bus interface?

The SN74LS641-1DWG4 uses a single common DIR control pin that simultaneously sets all 8 channels to either A-to-B or B-to-A transmission. For a CPU write cycle DIR is asserted one way and for a read cycle it is inverted, typically driven by the CPU's R/W control line. This single-pin direction switching reduces glue logic in 8-bit memory bus designs operating at 5 V TTL levels.

What package and pin pitch does the SN74LS641-1DWG4 use, and how does the 20-pin SOIC compare to the DIP alternative for board density?

The SN74LS641-1DWG4 comes in a 20-pin SOIC (JEDEC R-PDSO-G20) with a 1.27 mm pin pitch, occupying roughly 49 mm² of board area. Compared to a 20-pin DIP at 2.54 mm pitch which occupies about 185 mm², the SOIC saves over 70% of board space, making it the preferred choice for compact industrial controller PCBs while maintaining the same 8-channel bus transceiver functionality.

Related Guides

Why Buy from FindMyChip

Authorized Source
Verified supply chain with full traceability & inspection
Competitive Pricing
Factory-direct from China distributors, low MOQ
Fast Shipping
DHL Express 3–5 days · FedEx/UPS 5–7 days worldwide
Quality Guaranteed
30-day replacement for defective parts, no questions asked

About Texas Instruments

Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.

AvailabilityIn Stock
Reference Price (USD)
Contact for Price
Buy from 1pc · Factory-direct pricing
pcs

In Stock · 24h Response · Worldwide Shipping

Lead Time3-7 business days
MOQFrom 1 piece
ShippingDHL / FedEx / UPS
OriginChina (Authorized)

Response within 24 hours · Worldwide shipping

Their engineering team helped us find a pin-compatible alternative when our original MCU went EOL.

MR
Marco Rossi
CTO, AutoDrive Systems, Italy