SN74HC74DT Equivalent & Substitute Parts

Part Overview

The SN74HC74DT is a dual D-type flip-flop logic integrated circuit manufactured by Texas Instruments in 14-SOIC surface mount packaging. This component functions as a Set/Preset and Reset flip-flop with complementary outputs, designed for digital logic applications requiring edge-triggered storage elements. The SN74HC74DT is currently listed as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity.

Key Parameters

Parameter	Value
Manufacturer Part Number	SN74HC74DT
Manufacturer	Texas Instruments
Category	Logic
Type	D-Type Flip-Flop
Number of Elements	2
Number of Bits per Element	1
Output Type	Complementary
Trigger Type	Positive Edge
Clock Frequency	60 MHz
Max Propagation Delay @ 6V, 50pF	30 ns
Voltage Supply Range	2V to 6V
Current - Output High/Low	5.2 mA / 5.2 mA
Current - Quiescent (Iq)	4 µA
Input Capacitance	3 pF
Operating Temperature Range	-40°C to 85°C
Package / Case	14-SOIC (0.154", 3.90mm Width)
Mounting Type	Surface Mount
Product Status	Obsolete
RoHS Status	ROHS3 Compliant
Moisture Sensitivity Level (MSL)	1 (Unlimited)

Substitute Part Grouping Explanation

Substitute parts for the SN74HC74DT are classified based on functional and electrical compatibility within the 74HC74 logic family. The primary substitution criteria are:

Functional Equivalence: All substitute parts maintain the same D-type flip-flop architecture with dual elements, complementary outputs, and positive edge triggering.

Package Compatibility: All listed substitutes use 14-SOIC surface mount packaging with identical 0.154" (3.90mm) width, ensuring direct PCB footprint compatibility.

Electrical Parameters: Substitutes must operate within the 2V to 6V supply voltage range and maintain compatible propagation delay characteristics for timing-critical applications. Clock frequency, output current, and quiescent current variations are acceptable within the 74HC logic family specifications.

Operating Temperature: Substitutes with extended temperature ranges (-55°C to 125°C or -40°C to 125°C) provide enhanced reliability for industrial and automotive applications compared to the standard -40°C to 85°C range.

Manufacturer Variants: Equivalent parts from onsemi (MC74HC74ADR2G, MC74HC74ADG), NXP Semiconductors (74HC74D,653, 74HC74D/AUJ), Nexperia USA Inc. (74HC74D-Q100,118), and Fairchild Semiconductor (74VHC74M) provide functional equivalence with potential performance enhancements or extended certifications.

Parameter Comparison

Part Number	Manufacturer	Clock Frequency (MHz)	Max Propagation Delay @ 6V, 50pF (ns)	Voltage Supply (V)	Output Current High/Low (mA)	Quiescent Current (µA)	Operating Temperature (°C)	Product Status	Package
SN74HC74DT	Texas Instruments	60	30	2-6	5.2 / 5.2	4	-40 to 85	Obsolete	14-SOIC
SN74HCS74DR	Texas Instruments	105	15	2-6	7.8 / 7.8	2	-40 to 125	Active	14-SOIC
SN74HC74DR	Texas Instruments	60	15	2-6	5.2 / 5.2	4	-40 to 85	Active	14-SOIC
SN74HC74DRG4	Texas Instruments	60	30	2-6	5.2 / 5.2	4	-40 to 85	Discontinued at DiGi Electronics	14-SOIC
MC74HC74ADR2G	onsemi	35	17	2-6	5.2 / 5.2	2	-55 to 125	Active	14-SOIC
74HC74D,653	NXP Semiconductors	82	37	2-6	5.2 / 5.2	40	-40 to 125	Active	14-SOIC
74HC74D-Q100,118	Nexperia USA Inc.	82	37	2-6	5.2 / 5.2	40	-40 to 125	Active	14-SOIC
74HC74D/AUJ	NXP USA Inc.	82	37	2-6	5.2 / 5.2	40	-40 to 125	Active	14-SOIC
74VHC74M	Fairchild Semiconductor	115	9.3	2-5.5	8 / 8	2	-40 to 85	Active	14-SOIC
MC74HC74ADG	onsemi	35	17	2-6	5.2 / 5.2	2	-55 to 125	Active	14-SOIC

Engineering Selection Recommendations

Primary Recommendation - Active Status with Minimal Parameter Variance: SN74HC74DR (Texas Instruments) is the direct parametric equivalent with active product status. It maintains identical electrical characteristics to the SN74HC74DT while offering improved propagation delay (15 ns vs. 30 ns) and is available in Cut Tape and Digi-Reel packaging.

Enhanced Performance Option: SN74HCS74DR (Texas Instruments) provides superior performance with 105 MHz clock frequency, 15 ns propagation delay, and extended operating temperature range (-40°C to 125°C). This part is recommended for applications requiring higher speed or broader temperature operation.

Extended Temperature Range Selection: MC74HC74ADR2G and MC74HC74ADG (onsemi) offer -55°C to 125°C operating range with active product status, suitable for industrial and automotive environments. Both maintain compatible electrical parameters with reduced quiescent current (2 µA).

Automotive Grade Option: 74HC74D-Q100,118 (Nexperia USA Inc.) carries AEC-Q100 automotive qualification with active status, appropriate for automotive applications requiring certified components.

High-Speed Alternative: 74VHC74M (Fairchild Semiconductor) delivers the fastest propagation delay (9.3 ns) and highest clock frequency (115 MHz) for timing-critical applications, though with slightly reduced supply voltage range (2V to 5.5V).

Avoid: SN74HC74DRG4 is discontinued at DiGi Electronics and should not be selected for new designs. 74HCT138D,653 is a decoder/demultiplexer with different functionality and is not a valid substitute.

Frequently Asked Questions (FAQ)

Q: Can SN74HC74DR directly replace SN74HC74DT without design modifications? A: Yes. SN74HC74DR is a parametric equivalent with identical package, pinout, and core electrical specifications. The improved propagation delay (15 ns vs. 30 ns) is a performance enhancement that does not require circuit redesign.

Q: What is the difference between SN74HCS74DR and SN74HC74DR? A: SN74HCS74DR is an enhanced variant with higher clock frequency (105 MHz vs. 60 MHz), faster propagation delay (15 ns vs. 15 ns for the DR variant), lower quiescent current (2 µA vs. 4 µA), and extended temperature range (-40°C to 125°C vs. -40°C to 85°C). Both are active products from Texas Instruments.

Q: Are onsemi MC74HC74ADR2G and MC74HC74ADG interchangeable? A: Yes. Both are onsemi 74HC74 variants with identical electrical parameters. MC74HC74ADR2G is supplied in Cut Tape and Digi-Reel packaging, while MC74HC74ADG is supplied in Tube packaging. Selection depends on packaging preference and inventory requirements.

Q: Why do NXP parts (74HC74D,653, 74HC74D/AUJ) show higher quiescent current (40 µA)? A: The higher quiescent current is a characteristic of these specific NXP variants. While still within acceptable limits for most applications, this should be considered in power-sensitive designs. Texas Instruments and onsemi variants maintain lower quiescent current (2-4 µA).

Q: Is 74VHC74M suitable for all applications requiring SN74HC74DT? A: 74VHC74M is functionally compatible but has a reduced supply voltage range (2V to 5.5V vs. 2V to 6V). Verify that your application operates within this narrower range. The part offers superior speed performance (9.3 ns propagation delay) if voltage compatibility is confirmed.

Q: What does the "Q100" designation in 74HC74D-Q100,118 indicate? A: The Q100 designation indicates AEC-Q100 automotive qualification. This part is certified for automotive applications and is recommended when automotive-grade components are required by design specifications or customer requirements.

Q: Can I use 74HCT138D,653 as a substitute? A: No. 74HCT138D,653 is a decoder/demultiplexer with fundamentally different functionality (1 x 3:8 decoder vs. dual D-type flip-flop). It is not a valid substitute and will not function in circuits designed for the SN74HC74DT.

Q: What packaging options are available for active substitutes? A: Active substitutes are available in multiple packaging formats: Cut Tape (CT) & Digi-Reel (SN74HC74DR, MC74HC74ADR2G), Tape & Reel (SN74HCS74DR, 74HC74D-Q100,118), and Tube (MC74HC74ADG). Selection depends on production volume and assembly requirements.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message