SN74HC166DT Equivalent & Substitute Parts

Part Overview

The SN74HC166DT is an 8-bit parallel-in/serial-out shift register manufactured by Texas Instruments in 16-SOIC surface mount packaging. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing production and maintenance applications. The 74HC166 logic family provides parallel or serial to serial conversion functionality across the 2V to 6V supply voltage range, suitable for digital logic applications requiring data shifting operations.

Substiute Parts

SN74HC166DT

Texas InstrumentsIn Stock: 850SN74HC166DT Datasheet

Current PartRFQ

SN74HC166AIDREP

Texas InstrumentsIn Stock: 1032SN74HC166AIDREP Datasheet

Parametric EquivalentRFQ

SN74HC166AIDRQ1

Texas InstrumentsIn Stock: 806SN74HC166AIDRQ1 Datasheet

Parametric EquivalentRFQ

SN74HC166DR

Texas InstrumentsIn Stock: 2575SN74HC166DR Datasheet

Parametric EquivalentRFQ

SN74HC166DRG4

Texas InstrumentsIn Stock: 2894SN74HC166DRG4 Datasheet

Parametric EquivalentRFQ

74HC166D,653

Nexperia USA Inc.In Stock: 328474HC166D,653 Datasheet

DirectRFQ

74HC166D-Q100J

Nexperia USA Inc.In Stock: 291674HC166D-Q100J Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74HC166DT is determined by strict equivalence across the following parameters: logic type (shift register), bit configuration (8-bit single element), function (parallel or serial to serial), output type (push-pull), supply voltage range (2V ~ 6V), package type (16-SOIC), and mounting method (surface mount). All substitute parts listed maintain these core electrical and mechanical specifications. Product status variations (active versus obsolete) and packaging format differences (tape & reel versus cut tape) do not affect functional equivalence. Operating temperature range extensions and automotive qualifications represent enhancements rather than restrictions on substitution eligibility.

Parameter Comparison

Engineering Selection Recommendations

For direct functional replacement of the obsolete SN74HC166DT, select from active product status parts to ensure long-term supply continuity. SN74HC166AIDREP and SN74HC166DR from Texas Instruments maintain identical operating temperature specifications (-40°C ~ 85°C) and represent the closest functional equivalents. The Nexperia USA Inc. alternatives (74HC166D,653 and 74HC166D-Q100J) provide extended operating temperature range (-40°C ~ 125°C), offering thermal margin for demanding applications without functional compromise.

For automotive applications requiring AEC-Q100 qualification, select SN74HC166AIDRQ1 (Texas Instruments) or 74HC166D-Q100J (Nexperia USA Inc.). Both parts meet automotive-grade standards while maintaining full electrical equivalence to the original SN74HC166DT.

Packaging format selection depends on procurement workflow: tape & reel formats support automated assembly processes, while cut tape options accommodate lower-volume or mixed-component orders. All substitute parts are ROHS3 compliant with MSL 1 rating, matching the original part's environmental compliance profile.

Frequently Asked Questions (FAQ)

Q: Can SN74HC166AIDREP directly replace SN74HC166DT in existing designs? A: Yes. Both parts share identical electrical specifications (2V ~ 6V supply, -40°C ~ 85°C operating range, 8-bit shift register function, push-pull output, 16-SOIC package). The primary difference is product status (active versus obsolete) and packaging format (tape & reel versus tube).

Q: What is the difference between SN74HC166DR and SN74HC166DRG4? A: Both parts are functionally equivalent 8-bit shift registers in 16-SOIC packaging from Texas Instruments. SN74HC166DRG4 is discontinued at DiGi Electronics, while SN74HC166DR remains in active distribution. Electrical performance is identical.

Q: Why do Nexperia parts show -40°C ~ 125°C operating temperature instead of -40°C ~ 85°C? A: The Nexperia 74HC166D,653 and 74HC166D-Q100J are rated for extended temperature operation. This represents a specification enhancement and does not prevent substitution for applications requiring only -40°C ~ 85°C performance.

Q: Are automotive-qualified parts (AEC-Q100) required for non-automotive applications? A: No. AEC-Q100 qualification is an additional certification for automotive-grade reliability. Standard industrial-grade parts (SN74HC166AIDREP, SN74HC166DR, 74HC166D,653) are fully suitable for non-automotive digital logic applications.

Q: Does packaging format (tape & reel versus cut tape) affect electrical performance? A: No. Packaging format is a procurement and assembly consideration only. Tape & reel supports high-volume automated assembly, while cut tape accommodates lower-volume or mixed-component orders. Electrical specifications remain identical.

Q: Can I mix substitute parts from different manufacturers in the same design? A: Yes. All listed substitutes maintain identical electrical specifications for the 8-bit shift register function, 16-SOIC package, and operating parameters. Cross-manufacturer substitution is electrically valid.