SN74ALS166D Equivalent & Substitute Parts

Part Overview

The SN74ALS166D is an 8-bit parallel-load shift register manufactured by Texas Instruments, designed for logic applications requiring serial-to-parallel or parallel-to-serial data conversion. This component operates within a 4.5V to 5.5V supply voltage range and is housed in a 16-SOIC surface mount package. The main part is currently in Last Time Buy status, indicating limited availability and the necessity to identify functionally equivalent alternatives for ongoing production and maintenance applications.

Substiute Parts

SN74ALS166D

Texas InstrumentsIn Stock: 1160SN74ALS166D Datasheet

Current PartRFQ

SN74ALS166DR

Texas InstrumentsIn Stock: 1167SN74ALS166DR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74ALS166D is determined by strict equivalence across the following critical parameters:

• Logic Type: Shift Register (8-bit configuration)
• Function: Parallel or Serial to Serial conversion capability
• Output Type: Push-Pull
• Voltage Supply Range: 4.5V ~ 5.5V
• Operating Temperature Range: 0°C ~ 70°C
• Package / Case: 16-SOIC form factor with identical pin configuration
• Base Product Number: 74ALS166 series designation

The SN74ALS166DR qualifies as a direct substitute based on identical electrical specifications, functional characteristics, and mechanical packaging. The primary distinction between the main part and substitute is the packaging format: the SN74ALS166D is supplied in Tube packaging, while the SN74ALS166DR is supplied in Tape & Reel (TR) format. Both parts share the same silicon die and pinout configuration.

Parameter Comparison

Engineering Selection Recommendations

The SN74ALS166DR is the direct functional equivalent for the SN74ALS166D. Both parts maintain identical electrical performance, logic functionality, and mechanical compatibility within the 16-SOIC package footprint. The SN74ALS166DR is recommended for new designs and ongoing production due to its Active product status, ensuring long-term availability and supply chain continuity. Both parts satisfy ROHS3 compliance and REACH unaffected status, meeting current environmental and regulatory requirements. The selection between these parts should be based on packaging requirements: Tube format for low-volume or manual assembly operations, or Tape & Reel format for automated pick-and-place manufacturing processes.

Frequently Asked Questions (FAQ)

Q: Can the SN74ALS166DR be used as a direct replacement for the SN74ALS166D in existing designs?

A: Yes. The SN74ALS166DR is electrically and functionally identical to the SN74ALS166D. Both parts share the same 16-SOIC pinout, supply voltage range (4.5V ~ 5.5V), operating temperature range (0°C ~ 70°C), and shift register functionality. No circuit modifications are required.

Q: What is the difference between Tube and Tape & Reel packaging?

A: Tube packaging supplies components in plastic tubes suitable for manual handling and low-volume assembly. Tape & Reel packaging supplies components on continuous carrier tape wound on reels, optimized for automated pick-and-place assembly equipment. Both formats contain identical components with no electrical or functional differences.

Q: Are both parts RoHS compliant?

A: Yes. Both the SN74ALS166D and SN74ALS166DR are ROHS3 compliant and REACH unaffected, meeting current environmental regulations for electronic component manufacturing and use.

Q: Why is the SN74ALS166D listed as Last Time Buy?

A: Last Time Buy status indicates that the manufacturer has discontinued or is discontinuing production of this specific part number. The SN74ALS166DR, with Active product status, represents the ongoing production equivalent and is recommended for future procurement.

Q: What is the Moisture Sensitivity Level (MSL) significance?

A: Both parts carry MSL 1 (Unlimited), indicating no moisture sensitivity restrictions. These components do not require special moisture control during storage, handling, or assembly, simplifying logistics and manufacturing processes.