SN74LS166AD Equivalent & Substitute Parts

Part Overview

The SN74LS166AD is an 8-bit parallel-load shift register manufactured by Texas Instruments, housed in a 16-SOIC surface mount package. This logic component functions as a parallel or serial to serial converter, featuring push-pull output configuration. The SN74LS166AD is currently discontinued at DiGi Electronics, making identification of compatible substitute parts essential for ongoing design support and production continuity. Equivalent parts maintain identical electrical specifications and mechanical compatibility while offering alternative packaging or availability status.

Substiute Parts

SN74LS166AD

Texas InstrumentsIn Stock: 4384SN74LS166AD Datasheet

Current PartRFQ

SN74LS166ADR

Texas InstrumentsIn Stock: 3879SN74LS166ADR Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SN74LS166AD are identified based on strict equivalence across the following critical parameters:

• Logic Type: Shift Register
• Number of Elements: 1
• Number of Bits per Element: 8
• Function: Parallel or Serial to Serial
• Output Type: Push-Pull
• Voltage - Supply: 4.75V ~ 5.25V
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 16-SOIC (0.154", 3.90mm Width)
• Mounting Type: Surface Mount
• Base Product Number: 74LS166

The primary distinction between the main part and its substitute lies in packaging format and product availability status. The SN74LS166ADR maintains identical electrical and mechanical specifications while differing only in supply packaging configuration.

Parameter Comparison

Engineering Selection Recommendations

The SN74LS166ADR serves as the direct functional equivalent to the SN74LS166AD. Both parts are manufactured by Texas Instruments and maintain identical electrical characteristics, pin configuration, and mechanical dimensions. The SN74LS166ADR is currently in active product status, whereas the SN74LS166AD is discontinued. Both parts carry ROHS3 compliance and REACH unaffected status, meeting current environmental and regulatory requirements. The distinction between these parts is limited to packaging format: the SN74LS166AD is supplied in tube packaging, while the SN74LS166ADR is supplied in tape and reel format. Selection between these parts should be based on procurement requirements, inventory management practices, and assembly line compatibility with existing tape and reel or tube handling equipment.

Frequently Asked Questions (FAQ)

Q: Are the SN74LS166AD and SN74LS166ADR pin-compatible?

A: Yes. Both parts use the 16-SOIC package with identical pin assignments and electrical characteristics. They are direct functional replacements.

Q: What is the difference between tube and tape & reel packaging?

A: Tube packaging supplies individual components in plastic tubes, typically used for lower-volume applications or manual assembly. Tape and reel packaging supplies components on continuous carrier tape wound on reels, optimized for automated pick-and-place assembly equipment. The electrical and mechanical specifications of the component itself remain unchanged.

Q: Can I use the SN74LS166ADR as a substitute for the SN74LS166AD in existing designs?

A: Yes. The SN74LS166ADR is electrically and mechanically equivalent. Substitution is valid from a component specification standpoint. Verify that your assembly process can accommodate tape and reel packaging if switching from tube format.

Q: Why is the SN74LS166AD discontinued?

A: Product discontinuation decisions are made by manufacturers based on market demand and product lifecycle management. The SN74LS166ADR remains in active production and provides equivalent functionality.

Q: Are both parts RoHS compliant?

A: Yes. Both the SN74LS166AD and SN74LS166ADR are ROHS3 compliant and REACH unaffected, meeting current environmental regulations.