SN74ALS843DW Equivalent & Substitute Parts

Part Overview

The SN74ALS843DW is a D-Type Transparent Latch IC manufactured by Texas Instruments, featuring 9-bit configuration with tri-state output capability in a 24-SOIC surface mount package. This component is classified as Last Time Buy, indicating discontinued production status. The identification of equivalent substitute parts is necessary to ensure design continuity and procurement availability for applications currently utilizing this logic latch device.

Substiute Parts

SN74ALS843DW

Texas InstrumentsIn Stock: 1046SN74ALS843DW Datasheet

Current PartRFQ

SN74ALS843DWR

Texas InstrumentsIn Stock: 1043SN74ALS843DWR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74ALS843DW is determined by strict equivalence across the following critical parameters:

• Logic Type: D-Type Transparent Latch configuration
• Circuit Configuration: 9:9 bit organization
• Output Type: Tri-State capability
• Supply Voltage: 4.5V ~ 5.5V operating range
• Propagation Delay: 5ns timing specification
• Output Current Ratings: 2.6mA (high) and 24mA (low)
• Operating Temperature: 0°C ~ 70°C range
• Package: 24-SOIC form factor with identical pinout
• Base Product Number: 74ALS843 series designation

The SN74ALS843DWR qualifies as a direct substitute based on identical electrical specifications and package configuration. The distinction between these parts is limited to packaging format: tube versus tape & reel.

Parameter Comparison

Engineering Selection Recommendations

The SN74ALS843DWR is the direct equivalent substitute for the SN74ALS843DW. Both parts maintain identical electrical and functional specifications across all critical parameters. The primary distinction is product status: the SN74ALS843DW is designated Last Time Buy, while the SN74ALS843DWR maintains Active status with current manufacturing availability.

Selection between these parts should be based on procurement requirements and supply chain considerations. The SN74ALS843DWR is recommended for new designs and ongoing production due to its active product status. Both parts satisfy ROHS3 compliance and REACH unaffected requirements, ensuring regulatory alignment for industrial and commercial applications.

Frequently Asked Questions (FAQ)

Q: Are the SN74ALS843DW and SN74ALS843DWR electrically identical?

A: Yes. Both parts share identical electrical specifications including logic type, circuit configuration, output type, supply voltage range, propagation delay, output current ratings, and operating temperature range. They are functionally equivalent.

Q: What is the difference between these two part numbers?

A: The difference is limited to packaging format. The SN74ALS843DW is supplied in tube packaging, while the SN74ALS843DWR is supplied in tape & reel format. The electrical performance and pinout are identical.

Q: Can I use the SN74ALS843DWR as a direct replacement for the SN74ALS843DW?

A: Yes. The SN74ALS843DWR is a direct substitute. Both parts use the 24-SOIC package with identical pinout and electrical characteristics. PCB layout and circuit design require no modification.

Q: Why is the SN74ALS843DW marked as Last Time Buy?

A: Last Time Buy status indicates that Texas Instruments has discontinued production of this part number. The SN74ALS843DWR, with Active status, represents the current manufacturing equivalent and is recommended for procurement.

Q: Are there any compliance differences between these parts?

A: No. Both parts maintain identical RoHS3 compliance status and REACH unaffected designation. Regulatory requirements are satisfied by either part.

Q: What packaging considerations should I account for when switching between these parts?

A: The primary consideration is handling and assembly process. Tube packaging is suitable for manual assembly and lower-volume applications. Tape & reel packaging is optimized for automated pick-and-place assembly and higher-volume production. The electrical performance and board-level integration are unaffected by this distinction.