SN74LS74AD Equivalent & Substitute Parts

Part Overview

The SN74LS74AD is a dual D-type flip-flop logic integrated circuit manufactured by Texas Instruments, housed in a 14-SOIC surface mount package. This component functions as a Set/Preset and Reset element with complementary outputs, designed for digital logic applications requiring edge-triggered flip-flop functionality. The SN74LS74AD is currently discontinued at DiGi Electronics, making equivalent substitute parts necessary for ongoing production and maintenance applications.

Substiute Parts

SN74LS74AD

Texas InstrumentsIn Stock: 2054SN74LS74AD Datasheet

Current PartRFQ

SN74LS74ADR

Texas InstrumentsIn Stock: 2981SN74LS74ADR Datasheet

DirectRFQ

74ABT74D,118

Nexperia USA Inc.In Stock: 406074ABT74D,118 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SN74LS74AD are qualified based on the following electrical and mechanical parameters:

Critical Compatibility Parameters:

• Functional equivalence: Dual D-type flip-flop with Set/Preset and Reset functions
• Output configuration: Complementary outputs
• Trigger mechanism: Positive edge-triggered
• Package compatibility: 14-SOIC surface mount form factor
• Pin count and pinout: 14-pin configuration matching original design
• Supply voltage range: Minimum 4.75V operation capability
• Logic family compatibility: TTL or TTL-compatible logic levels

Substitution Categories:

1. Direct Functional Equivalent (Same Series): SN74LS74ADR maintains identical electrical specifications, series designation (74LS), and packaging while offering active product status and improved availability.

2. Enhanced Performance Substitute (Different Series): 74ABT74D,118 provides superior performance characteristics including higher clock frequency, faster propagation delay, and extended operating temperature range, while maintaining functional equivalence and 14-SOIC packaging.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (SN74LS74ADR): Select SN74LS74ADR when maintaining identical electrical performance specifications is required. This part is manufactured by Texas Instruments, maintains the 74LS series designation, and provides active product status with improved availability. Both parts operate within the same voltage supply range (4.75V ~ 5.25V) and temperature range (0°C ~ 70°C). The primary difference is packaging format: SN74LS74ADR is supplied in Cut Tape and Digi-Reel format versus the original Tube packaging. ROHS3 compliance and MSL rating are identical.

For Enhanced Performance (74ABT74D,118): Select 74ABT74D,118 when design specifications permit higher performance characteristics. This Nexperia part operates at 250 MHz clock frequency compared to 33 MHz, delivers 4.2ns propagation delay versus 40ns, and supports extended operating temperature range (-40°C ~ 85°C). The 74ABT series provides lower quiescent current (50 µA versus 8 mA) and higher output drive capability (15mA/20mA versus 400µA/8mA). Supply voltage range is slightly wider (4.5V ~ 5.5V). All parts maintain 14-SOIC packaging compatibility, ROHS3 compliance, and MSL-1 rating.

Frequently Asked Questions (FAQ)

Q: Can SN74LS74ADR be used as a direct replacement for SN74LS74AD?

A: Yes. Both parts are identical in electrical specifications, logic family (74LS), and 14-SOIC package configuration. The difference is packaging format: SN74LS74ADR uses Cut Tape and Digi-Reel supply versus Tube. Both are ROHS3 compliant with MSL-1 rating.

Q: What are the advantages of using 74ABT74D,118 over SN74LS74ADR?

A: The 74ABT74D,118 offers superior performance: 250 MHz clock frequency (versus 33 MHz), 4.2ns propagation delay (versus 40ns), extended temperature range (-40°C ~ 85°C versus 0°C ~ 70°C), and lower quiescent current (50 µA versus 8 mA). It maintains identical 14-SOIC packaging and functional equivalence.

Q: Are all three parts pin-compatible?

A: Yes. All three parts are 14-pin D-type flip-flops with identical pinout and 14-SOIC surface mount package dimensions (0.154", 3.90mm Width).

Q: What is the minimum supply voltage for each part?

A: SN74LS74AD and SN74LS74ADR require minimum 4.75V. The 74ABT74D,118 operates at minimum 4.5V, providing slightly wider voltage tolerance.

Q: Do all parts meet RoHS compliance requirements?

A: Yes. All three parts are ROHS3 compliant with MSL-1 (Unlimited) moisture sensitivity level rating.

Q: Which part should be selected for high-temperature applications?

A: The 74ABT74D,118 supports operating temperature range of -40°C ~ 85°C, compared to 0°C ~ 70°C for both 74LS variants. Select 74ABT74D,118 for applications requiring extended temperature operation.

Q: What is the current availability status of each part?

A: SN74LS74AD is discontinued at DiGi Electronics. SN74LS74ADR and 74ABT74D,118 are both active products with current inventory availability.