SN74F27D NOR Gate IC Equivalent & Substitute Parts

Part Overview

The SN74F27D is a 3-channel NOR gate logic IC manufactured by Texas Instruments in 14-SOIC surface mount packaging. This component implements three independent 3-input NOR logic functions and operates within the 4.5V to 5.5V supply voltage range. The SN74F27D is currently in Last Time Buy status, indicating end-of-life production. Identifying equivalent substitute parts is necessary to ensure design continuity and maintain supply chain reliability for applications requiring this logic function.

Substiute Parts

SN74F27D

Texas InstrumentsIn Stock: 2370SN74F27D Datasheet

Current PartRFQ

SN74F27DR

Texas InstrumentsIn Stock: 3895SN74F27DR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74F27D is determined by strict equivalence across the following critical parameters:

• Logic function: 3-channel, 3-input NOR gate configuration
• Electrical specifications: 4.5V to 5.5V supply voltage, 1mA/20mA output current ratings, 0.8V/2V input logic thresholds, 5ns maximum propagation delay at 5V with 50pF load
• Package format: 14-SOIC surface mount package with 0.154" (3.90mm) width
• Operating temperature range: 0°C to 70°C
• Series classification: 74F logic family

The SN74F27DR qualifies as a direct substitute based on identical electrical performance, logic configuration, and package specifications. The primary distinction is packaging format: the SN74F27D is supplied in Tube packaging, while the SN74F27DR is supplied in Tape & Reel format. Both parts share the same base product number (74F27) and maintain full functional and pin-level compatibility.

Parameter Comparison

Engineering Selection Recommendations

The SN74F27DR is the direct substitute for the SN74F27D. Both parts maintain identical electrical characteristics, logic function, and package specifications. The SN74F27DR carries Active product status, ensuring continued availability and manufacturing support, whereas the SN74F27D is in Last Time Buy status. Both parts are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements. Selection between these parts should be based on procurement requirements: the SN74F27D in Tube packaging is suitable for lower-volume or manual assembly operations, while the SN74F27DR in Tape & Reel format is optimized for automated assembly processes and higher-volume production runs.

Frequently Asked Questions (FAQ)

Q: Can the SN74F27DR replace the SN74F27D in existing designs?

A: Yes. The SN74F27DR is a direct functional and pin-level equivalent. Both parts implement identical 3-channel, 3-input NOR gate logic with matching electrical specifications, operating temperature range, and 14-SOIC package dimensions. No circuit modifications are required.

Q: What is the difference between Tube and Tape & Reel packaging?

A: Tube packaging supplies individual components in a plastic tube, suitable for manual handling and lower-volume assembly. Tape & Reel packaging supplies components on continuous carrier tape wound on reels, optimized for automated pick-and-place assembly equipment. Electrical and functional performance are identical.

Q: Why is the SN74F27D marked as Last Time Buy?

A: Last Time Buy status indicates the manufacturer has discontinued production and will not accept new orders after a specified date. Existing inventory may be available, but long-term supply cannot be guaranteed. The SN74F27DR, with Active status, is the recommended alternative for new designs and ongoing production.

Q: Are there any compliance differences between these parts?

A: No. Both the SN74F27D and SN74F27DR are ROHS3 compliant, REACH unaffected, and carry identical moisture sensitivity levels (MSL 1 - Unlimited). Regulatory compliance is equivalent.

Q: What are the critical parameters for substitution?

A: Substitution is valid when the following parameters match: logic type (3-channel, 3-input NOR gate), supply voltage range (4.5V ~ 5.5V), output current ratings (1mA/20mA), input logic thresholds (0.8V/2V), propagation delay (5ns @ 5V, 50pF), operating temperature (0°C ~ 70°C), and package format (14-SOIC surface mount). All parameters are identical between the SN74F27D and SN74F27DR.