74F109SCX Equivalent & Substitute Parts

Part Overview

The 74F109SCX is a dual JK-type flip-flop logic integrated circuit manufactured by onsemi, housed in a 16-SOIC surface mount package. This component is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. The 74F109 series provides Set/Preset and Reset functionality with complementary outputs, operating at positive edge trigger conditions suitable for digital logic applications requiring dual 1-bit flip-flop configurations.

Substiute Parts

74F109SCX

onsemiIn Stock: 175974F109SCX Datasheet

Current PartRFQ

SN74F109D

Texas InstrumentsIn Stock: 1668SN74F109D Datasheet

DirectRFQ

SN74F109DR

Texas InstrumentsIn Stock: 3680SN74F109DR Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 74F109SCX is determined by strict equivalence across the following critical parameters:

• Functional Type: JK-type dual flip-flop with 2 elements, 1 bit per element
• Output Configuration: Complementary outputs with Set/Preset and Reset functionality
• Trigger Mechanism: Positive edge triggering
• Electrical Specifications: Voltage supply range 4.5V ~ 5.5V, propagation delay 8 ns @ 5V/50pF, output current ratings 1 mA / 20 mA
• Package Compatibility: 16-SOIC (0.154", 3.90mm Width) surface mount package
• Quiescent Current: 17 mA maximum

The substitute parts SN74F109D and SN74F109DR, both manufactured by Texas Instruments, meet all functional and electrical requirements. Both maintain the 74F109 base product number designation and are pin-compatible within the same package footprint. Differences in product status and packaging format (Tube vs. Tape & Reel) do not affect electrical or mechanical compatibility.

Parameter Comparison

Engineering Selection Recommendations

SN74F109DR (Texas Instruments, Active Status) is the primary substitute for the obsolete 74F109SCX. This part maintains Active product status, ensuring long-term availability and supply chain continuity. The SN74F109DR is supplied in Tape & Reel packaging format, standard for high-volume production environments. Both RoHS3 compliance and REACH Unaffected status align with current regulatory requirements.

SN74F109D (Texas Instruments, Last Time Buy) serves as a secondary substitute option. While functionally equivalent and RoHS3 compliant, this part carries Last Time Buy status, indicating limited future availability. The Tube packaging format suits lower-volume or prototype applications.

Both Texas Instruments substitutes exceed the original 74F109SCX clock frequency specification (150 MHz vs. 125 MHz), providing performance margin. All other electrical and mechanical parameters remain equivalent, ensuring direct functional replacement without circuit redesign.

Frequently Asked Questions (FAQ)

Q: Can SN74F109D and SN74F109DR be used interchangeably with 74F109SCX?

A: Yes. Both parts are electrically and mechanically equivalent. The primary difference is packaging format (Tube vs. Tape & Reel) and product lifecycle status. Selection depends on production volume and supply requirements.

Q: What is the difference between SN74F109D and SN74F109DR?

A: Both parts are functionally identical with matching electrical specifications. SN74F109DR is supplied in Tape & Reel format for automated assembly; SN74F109D is supplied in Tube format. SN74F109DR maintains Active status, while SN74F109D is Last Time Buy.

Q: Are the pin configurations identical across all three parts?

A: Yes. All three parts use the 16-SOIC package with identical pinout. No PCB layout modifications are required for substitution.

Q: Do the substitute parts meet current compliance standards?

A: Both Texas Instruments substitutes are RoHS3 compliant and REACH Unaffected. The original 74F109SCX compliance status was not specified in available documentation.

Q: Why does the 74F109SCX show obsolete status?

A: The 74F109SCX is an onsemi product that has reached end-of-life. Texas Instruments continues to manufacture equivalent 74F109 variants, ensuring design continuity through direct substitution.

Q: What is the clock frequency difference, and does it affect compatibility?

A: The substitute parts operate at 150 MHz versus the original 125 MHz specification. This represents improved performance and does not create compatibility issues. Circuits designed for 125 MHz operation function correctly with 150 MHz parts.