SN74AS280D Equivalent & Substitute Parts

Part Overview

The SN74AS280D is a 9-bit parity generator/checker logic integrated circuit manufactured by Texas Instruments in the 74AS series. This component is classified as obsolete, which necessitates identification of functionally equivalent alternatives for ongoing design support and procurement. The SN74AS280D operates within the standard TTL voltage range and is housed in a 14-SOIC surface mount package. Due to its obsolete status, sourcing equivalent or substitute parts from active product lines is essential for system maintenance, redesign, and new production requirements.

Substiute Parts

SN74AS280D

Texas InstrumentsIn Stock: 870SN74AS280D Datasheet

Current PartRFQ

SN74F280BDR

Texas InstrumentsIn Stock: 3683SN74F280BDR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74AS280D is determined by the following critical parameters:

• Logic Function: Parity Generator/Checker with 9-bit configuration
• Package Compatibility: 14-SOIC surface mount package with identical physical dimensions (0.154", 3.90mm width)
• Electrical Specifications: Supply voltage range 4.5 V ~ 5.5 V and operating temperature range 0°C ~ 70°C
• Compliance Requirements: RoHS3 compliance and REACH unaffected status

The SN74F280BDR qualifies as a manufacturer-recommended substitute because it maintains functional equivalence in parity generation/checking logic, identical package form factor, and overlapping electrical operating parameters. The primary distinction lies in the logic family (74F versus 74AS), which affects output current characteristics but does not compromise functional compatibility within the specified voltage and temperature ranges.

Parameter Comparison

Engineering Selection Recommendations

The SN74F280BDR is the designated manufacturer-recommended substitute for the obsolete SN74AS280D. Both components maintain identical functional specifications for 9-bit parity generation and checking operations and are housed in the same 14-SOIC package footprint. Both parts satisfy RoHS3 compliance and REACH requirements, ensuring regulatory alignment for current manufacturing standards.

The SN74F280BDR offers the advantage of active product status, ensuring long-term availability and supply chain continuity. The output current differential (1mA high versus 2mA high for the original part) is within acceptable tolerance for standard TTL logic applications and does not affect functional parity checking performance. The SN74F280BDR is supplied in Tape & Reel packaging, which is standard for production environments.

Selection of the SN74F280BDR eliminates obsolescence risk while maintaining full functional and physical compatibility with existing designs utilizing the SN74AS280D.

Frequently Asked Questions (FAQ)

Q: Can the SN74F280BDR directly replace the SN74AS280D in existing designs?

A: Yes. Both parts are 9-bit parity generator/checker circuits in identical 14-SOIC packages with matching supply voltage ranges (4.5 V ~ 5.5 V) and operating temperature ranges (0°C ~ 70°C). Pin-for-pin compatibility and functional equivalence are maintained.

Q: What is the significance of the logic family difference (74F versus 74AS)?

A: The logic family designation indicates the underlying circuit technology and performance characteristics. The 74F series (Fast TTL) and 74AS series (Advanced Schottky) represent different generations of TTL logic. For parity checking applications, both families provide equivalent functional performance within the specified electrical parameters.

Q: Does the output current difference affect circuit operation?

A: The SN74F280BDR output high current is 1mA compared to 2mA for the SN74AS280D. This difference is not functionally significant for standard TTL logic applications. Both values are within acceptable TTL output specifications and do not compromise signal integrity or logic level compatibility.

Q: Are there packaging considerations when transitioning from SN74AS280D to SN74F280BDR?

A: The SN74AS280D is supplied in bulk packaging, while the SN74F280BDR is supplied in Tape & Reel (TR) format. Tape & Reel packaging is standard for automated assembly processes and offers improved handling and traceability for production environments. No circuit-level changes are required.

Q: What compliance certifications apply to both parts?

A: Both the SN74AS280D and SN74F280BDR are RoHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements for electronic component manufacturing and use.