74HCT161D,652 Equivalent & Substitute Parts

Part Overview

The 74HCT161D,652 is a 4-bit binary counter IC manufactured by NXP Semiconductors in a 16-SOIC surface mount package. This logic component functions as a synchronous counter with asynchronous reset, designed for positive edge triggering applications. The part is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement.

Substiute Parts

74HCT161D,652

NXP SemiconductorsIn Stock: 105974HCT161D,652 Datasheet

Current PartRFQ

CD74HCT161M

Harris CorporationIn Stock: 1671CD74HCT161M Datasheet

MFR RecommendedRFQ

CD74HCT161M96

Texas InstrumentsIn Stock: 3309CD74HCT161M96 Datasheet

MFR RecommendedRFQ

CD74HCT161MT

Texas InstrumentsIn Stock: 976CD74HCT161MT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the 74HCT161D,652 is determined by the following critical parameters:

• Logic Function: All substitute parts must be 4-bit binary counters with identical counting direction (up) and element configuration (1 element, 4 bits per element)
• Electrical Interface: Supply voltage range (4.5 V ~ 5.5 V), trigger type (positive edge), and reset mechanism (asynchronous) must match
• Package Compatibility: All substitutes must use the 16-SOIC package with identical physical dimensions (0.154", 3.90mm width) for direct PCB replacement
• Timing Characteristics: Synchronous timing operation is required; count rate variations are acceptable within the 74HCT logic family specification

The three substitute parts listed below meet these criteria and share the base product number 74HCT161, confirming functional equivalence within the 74HCT logic series.

Parameter Comparison

Engineering Selection Recommendations

CD74HCT161M96 (Texas Instruments) is the primary substitute for new designs and ongoing procurement. This part is currently active in production, carries ROHS3 compliance certification, and maintains full electrical and mechanical compatibility with the original 74HCT161D,652. The extended operating temperature range (-55°C ~ 125°C) provides additional margin for demanding applications.

CD74HCT161MT (Texas Instruments) serves as a secondary substitute with identical electrical specifications and ROHS3 compliance. This part is discontinued at DiGi Electronics but remains available through alternative distribution channels. It is suitable for replacement applications where inventory exists.

CD74HCT161M (Harris Corporation) is not recommended for new designs due to RoHS non-compliance status. This part may be considered only for legacy system maintenance where RoHS compliance is not a requirement and existing inventory is available.

All three substitutes are electrically interchangeable within the 74HCT logic family. The count rate difference (41 MHz vs. 20 MHz) reflects manufacturing variations within the 74HCT specification and does not affect functional compatibility in standard counter applications.

Frequently Asked Questions (FAQ)

Q: Can the CD74HCT161M96 be used as a direct replacement for the 74HCT161D,652?

A: Yes. Both parts share identical logic function, electrical specifications (4.5 V ~ 5.5 V supply, positive edge trigger, asynchronous reset), and 16-SOIC package dimensions. Direct PCB substitution is possible without circuit modification.

Q: What is the significance of the count rate difference (41 MHz vs. 20 MHz)?

A: Count rate variations within the 74HCT logic family reflect manufacturing process differences between suppliers. Both rates satisfy the 74HCT specification and do not affect functional compatibility in standard counter applications. Applications requiring specific timing margins should reference the detailed datasheet timing specifications.

Q: Why is the CD74HCT161M (Harris) not recommended?

A: The Harris part carries RoHS non-compliant status, which restricts its use in applications subject to RoHS regulations. For new designs and systems requiring regulatory compliance, the Texas Instruments alternatives (CD74HCT161M96 or CD74HCT161MT) are preferred.

Q: Are there any package or pinout differences between these substitutes?

A: No. All parts use the 16-SOIC package with identical physical dimensions (0.154", 3.90mm width) and pinout configuration. No PCB layout modifications are required for substitution.

Q: What is the difference between CD74HCT161M96 and CD74HCT161MT?

A: Both are Texas Instruments products with identical electrical specifications and ROHS3 compliance. The primary difference is product status: CD74HCT161M96 is active in production, while CD74HCT161MT is discontinued at DiGi Electronics. For new procurement, CD74HCT161M96 is the preferred choice.

Q: Can these parts be used in applications with operating temperatures below -40°C?

A: The substitute parts (CD74HCT161M, CD74HCT161M96, CD74HCT161MT) support operating temperatures down to -55°C, extending the range beyond the original 74HCT161D,652 specification of -40°C ~ 125°C. This provides additional margin for low-temperature applications.