SN74HC166PWG4 Equivalent & Substitute Parts

Part Overview

The SN74HC166PWG4 is an 8-bit parallel-in/serial-out shift register manufactured by Texas Instruments in a 16-TSSOP surface mount package. This component is classified as discontinued at DiGi Electronics, making identification of functionally equivalent alternatives essential for ongoing design support and procurement.

The shift register operates across a 2V to 6V supply voltage range and supports both parallel and serial input modes with push-pull output configuration. Discontinuation status necessitates evaluation of direct substitutes and upgraded alternatives that maintain electrical and mechanical compatibility.

Substiute Parts

SN74HC166PWG4

Texas InstrumentsIn Stock: 1116SN74HC166PWG4 Datasheet

Current PartRFQ

SN74HC166PWR

Texas InstrumentsIn Stock: 23519SN74HC166PWR Datasheet

DirectRFQ

74HC166PW,118

Nexperia USA Inc.In Stock: 256074HC166PW,118 Datasheet

UpgradeRFQ

74HC166PW-Q100J

Nexperia USA Inc.In Stock: 610574HC166PW-Q100J Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74HC166PWG4 is determined by strict equivalence across the following parameters:

Core Functional Parameters:

• Logic type: Shift Register
• Bit configuration: 1 element, 8 bits per element
• Function: Parallel or Serial to Serial
• Output type: Push-Pull

Electrical Parameters:

• Supply voltage range: 2V ~ 6V (minimum requirement)
• Operating temperature: -40°C minimum to 85°C minimum (upgrades may extend upper limit)

Mechanical Parameters:

• Package: 16-TSSOP surface mount
• Physical dimensions: 0.173" width, 4.40mm width

Compliance Parameters:

• RoHS3 compliance required
• MSL rating: 1 (Unlimited)

All identified substitutes maintain these core parameters. Variations in product status (active vs. discontinued), manufacturer, packaging format (tape & reel vs. cut tape), and extended temperature ranges represent upgrade or alternative sourcing options rather than functional deviations.

Parameter Comparison

Engineering Selection Recommendations

SN74HC166PWR (Direct Substitute): This Texas Instruments part maintains identical electrical and mechanical specifications to the SN74HC166PWG4 with active product status. It is the direct functional equivalent with the same operating temperature range (-40°C to 85°C) and supply voltage specification (2V to 6V). Packaging is available in cut tape and Digi-Reel formats. Selection of this part requires no design modification and provides continuity with the original component specification.

74HC166PW,118 (Upgrade Alternative): Manufactured by Nexperia USA Inc., this part extends the operating temperature range to -40°C to 125°C while maintaining all other electrical and mechanical parameters. This represents a performance upgrade suitable for applications requiring enhanced thermal performance. Packaging is supplied in tape and reel format. The extended temperature capability provides design margin for thermal stress conditions.

74HC166PW-Q100J (Manufacturer Recommended): This Nexperia part combines the extended temperature range (-40°C to 125°C) with automotive-grade qualification (AEC-Q100). It is designated as the manufacturer-recommended substitute and is suitable for automotive and mission-critical applications requiring formal qualification documentation. Tape and reel packaging is standard. This selection is appropriate when design specifications mandate automotive-grade components or when extended thermal performance is required.

All three substitutes maintain ROHS3 compliance, MSL rating of 1 (Unlimited), and identical functional parameters. Selection depends on product availability, thermal requirements, and application-specific qualification needs rather than functional compatibility.

Frequently Asked Questions (FAQ)

Q: Can SN74HC166PWR be used as a direct replacement for SN74HC166PWG4?

A: Yes. SN74HC166PWR is a direct functional equivalent. Both parts share identical logic type (8-bit shift register), electrical specifications (2V to 6V supply, -40°C to 85°C operating range), and 16-TSSOP package configuration. No design changes are required.

Q: What is the difference between the three substitute options?

A: SN74HC166PWR maintains the original specification. 74HC166PW,118 and 74HC166PW-Q100J extend the operating temperature range to -40°C to 125°C. The 74HC166PW-Q100J additionally carries automotive-grade qualification (AEC-Q100). All three are functionally equivalent for the core shift register operation.

Q: Does the extended temperature range of 74HC166PW,118 affect circuit design?

A: No. The extended temperature range represents improved performance capability, not a functional change. Circuits designed for -40°C to 85°C operation remain fully compatible. The extended range provides additional thermal margin for applications operating at elevated temperatures.

Q: Are all substitutes available in the same packaging formats?

A: No. SN74HC166PWR is available in cut tape and Digi-Reel formats. 74HC166PW,118 and 74HC166PW-Q100J are supplied in tape and reel format. Packaging format selection depends on procurement and assembly requirements rather than functional compatibility.

Q: Is the automotive-grade qualification of 74HC166PW-Q100J necessary for non-automotive applications?

A: No. AEC-Q100 qualification is specific to automotive applications. For standard industrial or consumer applications, SN74HC166PWR or 74HC166PW,118 provide equivalent functionality. Automotive qualification is required only when design specifications mandate it.

Q: Do all substitutes maintain RoHS3 compliance?

A: Yes. All three substitute parts are ROHS3 compliant with MSL rating of 1 (Unlimited), matching the original SN74HC166PWG4 specification.

Q: Can these parts be used interchangeably on the same PCB assembly?

A: Yes. All parts use the 16-TSSOP package with identical pinout and mechanical dimensions (0.173" width, 4.40mm width). They are mechanically and electrically interchangeable without PCB modification.