74AC251SCX Equivalent & Substitute Parts

Part Overview

The 74AC251SCX is a 1 x 8:1 multiplexer logic integrated circuit manufactured by onsemi in a 16-SOIC surface mount package. This part is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. The 74AC251 series provides single-supply multiplexing functionality suitable for digital logic applications requiring channel selection and data routing.

Substiute Parts

74AC251SCX

onsemiIn Stock: 1355974AC251SCX Datasheet

Current PartRFQ

CD74AC251M

Texas InstrumentsIn Stock: 1978CD74AC251M Datasheet

SimilarRFQ

CD74AC251M96

Texas InstrumentsIn Stock: 5130CD74AC251M96 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 74AC251SCX are qualified based on the following criteria:

• Circuit Configuration: Identical 1 x 8:1 multiplexer topology
• Package Compatibility: 16-SOIC surface mount package with matching pinout
• Electrical Compatibility: Single supply voltage operation with overlapping or extended supply voltage ranges
• Functional Equivalence: Same base product number (74AC251) ensuring pin-for-pin compatibility
• Compliance Standards: REACH and RoHS compliance status for regulatory alignment

The substitute parts CD74AC251M and CD74AC251M96 from Texas Instruments meet these criteria while offering improved availability and active product status.

Parameter Comparison

Engineering Selection Recommendations

CD74AC251M96 is the primary substitute for new designs and production. This part maintains active product status, ensuring long-term availability and supply chain stability. It provides ROHS3 compliance and extended operating temperature range (-55°C ~ 125°C) compared to the original 74AC251SCX. The higher output current capability (75mA versus 24mA) offers improved drive capability for downstream logic circuits. Tape & Reel packaging supports automated assembly processes.

CD74AC251M serves as a secondary substitute option, offering identical electrical specifications to CD74AC251M96 with tube packaging suitable for lower-volume applications. This part is discontinued at DiGi Electronics but may remain available through alternative distribution channels.

Both Texas Instruments substitutes are pin-for-pin compatible with the 74AC251SCX and operate within overlapping voltage supply ranges. The extended temperature range of the TI parts accommodates more demanding environmental conditions than the original onsemi device.

Frequently Asked Questions (FAQ)

Q: Are CD74AC251M and CD74AC251M96 pin-for-pin compatible with 74AC251SCX?

A: Yes. All three parts share the same base product number (74AC251) and 16-SOIC package, ensuring identical pinout and functional compatibility.

Q: What is the difference between CD74AC251M and CD74AC251M96?

A: Both parts have identical electrical specifications. The primary difference is packaging format: CD74AC251M uses tube packaging, while CD74AC251M96 uses Tape & Reel format. CD74AC251M96 is the active product with better long-term availability.

Q: Can I use the Texas Instruments substitutes in applications designed for 74AC251SCX?

A: Yes, with consideration of the extended specifications. The TI parts operate at lower minimum voltage (1.5V versus 2V) and higher maximum temperature (-55°C versus -40°C minimum), providing broader operational margins. Output current is higher (75mA versus 24mA), which is beneficial for driving additional logic loads.

Q: Are the substitute parts RoHS compliant?

A: CD74AC251M and CD74AC251M96 are ROHS3 compliant. The original 74AC251SCX RoHS status is not specified in available documentation.

Q: What packaging should I specify for new production orders?

A: CD74AC251M96 in Tape & Reel format is recommended for automated assembly. CD74AC251M in tube packaging is suitable for manual assembly or lower-volume builds.