PI74STX1G79CX Equivalent & Substitute Parts

Part Overview

The PI74STX1G79CX is a single D-type flip-flop logic integrated circuit manufactured by Diodes Incorporated in the 74STX series. This component functions as a standard D-type flip-flop with 1 element and 1 bit per element, featuring positive edge triggering and non-inverted outputs. The device is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. Substitute parts must maintain functional equivalence while meeting current manufacturing and compliance standards.

Substiute Parts

PI74STX1G79CX

Diodes IncorporatedIn Stock: 29376PI74STX1G79CX Datasheet

Current PartRFQ

SN74LVC1G79DBVT

Texas InstrumentsIn Stock: 2061SN74LVC1G79DBVT Datasheet

MFR RecommendedRFQ

SN74LVC1G79DCKR

Texas InstrumentsIn Stock: 23188SN74LVC1G79DCKR Datasheet

MFR RecommendedRFQ

SN74LVC1G79DCKT

Texas InstrumentsIn Stock: 1719SN74LVC1G79DCKT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the PI74STX1G79CX are selected based on strict functional and electrical equivalence. The following parameters determine substitution validity:

• Functional Type: D-Type flip-flop with 1 element, 1 bit per element, positive edge trigger, non-inverted output
• Electrical Compatibility: Supply voltage range 1.65V ~ 5.5V, output current capability 32mA minimum
• Package Compatibility: Surface mount packages (SC-70-5, SOT-353, or SOT-23-5)
• Performance Threshold: Clock frequency minimum 150 MHz

All three substitute parts (SN74LVC1G79DBVT, SN74LVC1G79DCKR, SN74LVC1G79DCKT) meet these criteria. They are manufactured by Texas Instruments in the 74LVC series, which is the direct successor to the 74STX series. These parts maintain identical functional specifications while offering improved product status and compliance certifications.

Parameter Comparison

Engineering Selection Recommendations

All three substitute parts are functionally equivalent to the PI74STX1G79CX and are recommended for direct replacement in new designs and production applications.

SN74LVC1G79DCKR is the preferred substitute when package compatibility with the original SC-70-5 footprint is required. This part maintains identical pinout and package dimensions, enabling direct PCB layout compatibility without redesign.

SN74LVC1G79DCKT provides the same SC-70-5 package as the original part and is available in Tape & Reel packaging for high-volume production environments.

SN74LVC1G79DBVT offers an alternative in SOT-23-5 package format, suitable for applications where the smaller SOT-753 footprint is acceptable. This option provides flexibility in PCB layout optimization.

All three substitute parts are manufactured by Texas Instruments with active product status, ensuring long-term availability and supply chain stability. All substitutes are ROHS3 compliant, addressing regulatory requirements that the original obsolete part does not meet. The extended operating temperature range (-40°C ~ 125°C) of the substitute parts provides improved thermal performance compared to the original specification (-40°C ~ 85°C).

Frequently Asked Questions (FAQ)

Q: Can SN74LVC1G79DBVT be used as a direct replacement for PI74STX1G79CX?

A: SN74LVC1G79DBVT is functionally equivalent but uses SOT-23-5 package instead of SC-70-5. This requires PCB layout modification. If SC-70-5 footprint compatibility is required, use SN74LVC1G79DCKR or SN74LVC1G79DCKT instead.

Q: What is the difference between the three substitute parts?

A: All three parts are electrically identical. The differences are packaging format: SN74LVC1G79DCKR and SN74LVC1G79DCKT use SC-70-5 package (matching the original), while SN74LVC1G79DBVT uses SOT-23-5 package. SN74LVC1G79DCKR is supplied in Cut Tape & Digi-Reel format, while SN74LVC1G79DCKT and SN74LVC1G79DBVT are supplied in Tape & Reel format.

Q: Are there any electrical differences between the original and substitute parts?

A: The substitute parts have identical functional specifications and electrical performance. Minor differences include quiescent current (10 µA vs. 2 µA) and input capacitance (4 pF vs. 3 pF), which do not affect functional compatibility. The substitute parts offer extended operating temperature range (-40°C ~ 125°C vs. -40°C ~ 85°C).

Q: Is the PI74STX1G79CX still available?

A: The PI74STX1G79CX is classified as obsolete. Substitute parts from Texas Instruments are recommended for all new designs and ongoing production.

Q: Do the substitute parts meet current compliance standards?

A: All three substitute parts are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements. The original PI74STX1G79CX is RoHS non-compliant.

Q: Which substitute part should I choose for new PCB designs?

A: For new designs, SN74LVC1G79DCKR or SN74LVC1G79DCKT are recommended if SC-70-5 package compatibility is preferred. SN74LVC1G79DBVT is suitable if SOT-23-5 package is acceptable and provides layout flexibility.