74HCT251N,652 Equivalent & Substitute Parts

Part Overview

The 74HCT251N,652 is a logic multiplexer IC with a 1 x 8:1 circuit configuration, manufactured by NXP USA Inc. in a 16-DIP through-hole package. This part is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement continuity. The device operates on a single 4.5V to 5.5V supply and is suitable for applications requiring 8-to-1 data selection with standard TTL-compatible logic levels.

Substiute Parts

74HCT251N,652

NXP USA Inc.In Stock: 74974HCT251N,652 Datasheet

Current PartRFQ

CD74HCT251E

Harris CorporationIn Stock: 6386CD74HCT251E Datasheet

DirectRFQ

74HCT251D,652

Nexperia USA Inc.In Stock: 73174HCT251D,652 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the 74HCT251N,652 is determined by the following critical parameters:

• Functional equivalence: Multiplexer type with 1 x 8:1 circuit configuration
• Electrical compatibility: Single supply voltage range 4.5V ~ 5.5V, output current 4mA / 4mA
• Operating temperature range: Minimum -40°C or lower, maximum 125°C or higher
• Package compatibility: 16-pin DIP or surface-mount equivalent (16-SO)
• Base product number alignment: 74HCT251 series

Two substitute parts meet these criteria:

1. CD74HCT251E (Harris Corporation) – Direct functional equivalent in 16-DIP package
2. 74HCT251D,652 (Nexperia USA Inc.) – Functional equivalent in 16-SO surface-mount package

Both substitutes maintain identical circuit functionality, electrical specifications, and supply voltage requirements. The primary difference is mounting technology and RoHS compliance status.

Parameter Comparison

Engineering Selection Recommendations

For through-hole PCB designs: CD74HCT251E provides direct pin-compatible substitution in the 16-DIP package. Note that this part carries RoHS non-compliant status, which may impact procurement for regulated applications.

For surface-mount PCB designs or RoHS3 compliance requirements: 74HCT251D,652 is the recommended substitute. This part maintains ROHS3 compliance and identical electrical specifications while requiring PCB layout modification to accommodate the 16-SOIC package footprint.

For extended temperature range applications: CD74HCT251E supports -55°C minimum operating temperature, compared to -40°C for the main part and 74HCT251D,652. This provides additional thermal margin if required.

All three parts are classified as obsolete. Selection should prioritize current inventory availability and compliance requirements specific to the end application.

Frequently Asked Questions (FAQ)

Q: Can CD74HCT251E be used as a direct replacement for 74HCT251N,652?

A: Yes. Both parts are 16-DIP through-hole packages with identical 1 x 8:1 multiplexer functionality, electrical specifications, and pin configurations. No PCB layout changes are required. RoHS compliance status differs between the parts.

Q: What is the primary difference between CD74HCT251E and 74HCT251D,652?

A: The primary difference is package type. CD74HCT251E uses a 16-DIP through-hole package, while 74HCT251D,652 uses a 16-SOIC surface-mount package. Both maintain identical electrical performance and circuit functionality. PCB layout and assembly process modifications are required when switching between these package types.

Q: Are there any electrical performance differences between these substitutes?

A: No. All three parts share identical output current specifications (4mA / 4mA), supply voltage range (4.5V ~ 5.5V), and circuit configuration (1 x 8:1). CD74HCT251E offers a wider operating temperature range (-55°C ~ 125°C) compared to the other two parts (-40°C ~ 125°C).

Q: Does RoHS compliance status affect electrical compatibility?

A: No. RoHS compliance is a material composition and environmental standard, not an electrical specification. CD74HCT251E is RoHS non-compliant while maintaining full electrical equivalence. Selection based on RoHS status depends on end-application regulatory requirements, not functional performance.

Q: Can 74HCT251D,652 be used in a through-hole PCB design?

A: No. The 74HCT251D,652 is a surface-mount component in a 16-SOIC package. Through-hole PCB designs require either 74HCT251N,652 or CD74HCT251E, both available in 16-DIP packages.