CD74HC123E Equivalent & Substitute Parts

Part Overview

The CD74HC123E is a monostable multivibrator logic integrated circuit manufactured by Texas Instruments, housed in a 16-DIP through-hole package. This device features two independent circuits with a 25 ns propagation delay and operates across a 2 V to 6 V supply voltage range. The product is classified as obsolete, making identification of functionally equivalent alternatives essential for design continuity and procurement planning.

Substiute Parts

CD74HC123E

Texas InstrumentsIn Stock: 20096CD74HC123E Datasheet

Current PartRFQ

CD74HC123PWR

Texas InstrumentsIn Stock: 50164CD74HC123PWR Datasheet

MFR RecommendedRFQ

TC74HC123APNEWF

Toshiba Semiconductor and StorageIn Stock: 1593TC74HC123APNEWF Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the CD74HC123E is determined by the following critical parameters:

Core Functional Requirements:

• Logic type: Monostable multivibrator
• Independent circuits: 2
• Supply voltage range: 2 V ~ 6 V (minimum overlap required)
• Output current capability: 5.2 mA minimum (both high and low)
• RoHS3 compliance

Package Compatibility Considerations:

• Through-hole mounting (16-DIP) is the primary package requirement for direct socket replacement
• Surface-mount alternatives (16-TSSOP) are functionally equivalent but require PCB redesign

Performance Parameters:

• Propagation delay tolerance: Faster alternatives (16 ns) are acceptable; slower alternatives must not exceed application timing requirements
• Operating temperature range: Substitutes must support the required application temperature window

Two substitute parts meet these criteria with different trade-offs in packaging and performance characteristics.

Parameter Comparison

Engineering Selection Recommendations

CD74HC123PWR (Texas Instruments, Surface Mount)

This substitute maintains identical electrical specifications to the CD74HC123E, including propagation delay and output current ratings. It is manufactured by the same supplier and carries active product status with full RoHS3 compliance. Selection of this part requires PCB redesign to accommodate the 16-TSSOP surface-mount package. This option is suitable for new designs or board revisions where surface-mount assembly is preferred.

TC74HC123APNEWF (Toshiba Semiconductor and Storage, Through Hole)

This substitute provides direct socket compatibility with the CD74HC123E through identical 16-DIP through-hole packaging. It delivers improved propagation delay performance at 16 ns compared to the original 25 ns specification. The device includes Schmitt trigger input functionality and maintains all critical electrical parameters. Operating temperature range is narrower (-40°C to 85°C) compared to the original (-55°C to 125°C), requiring verification against application requirements. This part is actively manufactured and fully RoHS3 compliant, making it suitable for direct replacement in existing designs where the narrower temperature range is acceptable.

Frequently Asked Questions (FAQ)

Q: Can CD74HC123PWR be used as a direct replacement for CD74HC123E?

A: CD74HC123PWR is electrically equivalent but requires PCB redesign. The main part uses 16-DIP through-hole packaging while the substitute uses 16-TSSOP surface-mount packaging. No socket compatibility exists without adapter solutions.

Q: What is the primary advantage of TC74HC123APNEWF over the original CD74HC123E?

A: TC74HC123APNEWF offers faster propagation delay (16 ns versus 25 ns) while maintaining through-hole 16-DIP package compatibility. This allows direct socket replacement without PCB modification.

Q: Does TC74HC123APNEWF have a narrower operating temperature range?

A: Yes. TC74HC123APNEWF operates from -40°C to 85°C, compared to the CD74HC123E range of -55°C to 125°C. Applications requiring operation below -40°C or above 85°C must use alternative solutions.

Q: Are all three parts RoHS3 compliant?

A: Yes. CD74HC123E, CD74HC123PWR, and TC74HC123APNEWF all carry ROHS3 compliance certification.

Q: What does the Schmitt trigger input on TC74HC123APNEWF provide?

A: Schmitt trigger input provides hysteresis on the input signal, improving noise immunity. The original CD74HC123E does not include this feature. Applications sensitive to input noise may benefit from this enhancement.

Q: Which substitute should be selected for a new design?

A: Selection depends on packaging requirements. For through-hole assembly, TC74HC123APNEWF is recommended if the -40°C to 85°C temperature range is acceptable. For surface-mount assembly, CD74HC123PWR is the appropriate choice.