MM74HC4020N Equivalent & Substitute Parts

Part Overview

The MM74HC4020N is a 14-bit binary counter logic IC manufactured by onsemi, housed in a 16-DIP package for through-hole mounting. This component functions as a single-element counter with asynchronous reset capability, designed for negative-edge triggering applications. The part is classified as obsolete, making equivalent substitutes necessary for ongoing design support and procurement continuity.

Substiute Parts

MM74HC4020N

onsemiIn Stock: 1506MM74HC4020N Datasheet

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CD74HC4020E

Harris CorporationIn Stock: 1624CD74HC4020E Datasheet

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SN74HC4020N

Texas InstrumentsIn Stock: 2650SN74HC4020N Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MM74HC4020N is determined by strict alignment with the following core parameters:

• Base product number: 74HC4020
• Logic type: Binary counter with 14-bit, single-element configuration
• Trigger mechanism: Negative edge
• Reset function: Asynchronous
• Supply voltage range: 2 V ~ 6 V (minimum overlap required)
• Package: 16-DIP through-hole form factor
• Pin configuration: 16-PDIP supplier device package

The identified substitutes (CD74HC4020E and SN74HC4020N) meet all mandatory electrical and mechanical compatibility criteria. Variations in count rate, operating temperature range, and product status are noted but do not preclude functional substitution within the specified voltage and logic parameters.

Parameter Comparison

Engineering Selection Recommendations

SN74HC4020N (Texas Instruments) is the preferred substitute for new designs and ongoing procurement. This part maintains active product status, ensuring long-term availability and manufacturer support. The SN74HC4020N is ROHS3 compliant, meeting current environmental and regulatory requirements. Operating temperature range (-40°C ~ 85°C) matches the original MM74HC4020N specification.

CD74HC4020E (Harris Corporation) provides functional equivalence but carries obsolete product status and RoHS non-compliance. This part is suitable only for legacy system maintenance where regulatory compliance is not a requirement.

Both substitutes operate within the specified 2 V ~ 6 V supply voltage range and maintain identical logic configuration (14-bit binary counter, asynchronous reset, negative-edge trigger). Count rate differences (50 MHz original vs. 35 MHz and 33 MHz for substitutes) must be evaluated against specific application timing requirements.

Frequently Asked Questions (FAQ)

Q: Can the CD74HC4020E or SN74HC4020N be used as direct pin-for-pin replacements for the MM74HC4020N?

A: Yes. All three parts share identical 16-DIP package geometry, pin count, and functional logic configuration. Direct substitution is mechanically and electrically feasible without PCB modification.

Q: What is the significance of the count rate difference between the MM74HC4020N (50 MHz) and its substitutes (35 MHz and 33 MHz)?

A: Count rate represents the maximum frequency at which the counter can reliably toggle. Applications operating below 33 MHz experience no functional impact. Designs requiring operation above 35 MHz must verify timing compatibility with the substitute part's specifications.

Q: Why is the MM74HC4020N classified as obsolete?

A: Obsolete status indicates the manufacturer has discontinued production. Existing inventory may be available through authorized distributors, but long-term procurement cannot be guaranteed. Substitution to active-status parts (such as SN74HC4020N) is recommended for new designs.

Q: Does RoHS compliance affect functional performance?

A: RoHS compliance does not alter electrical or logic performance. It reflects manufacturing process restrictions on hazardous substances. For applications subject to environmental regulations or customer requirements, ROHS3-compliant parts (SN74HC4020N) are mandatory.

Q: Are there any package or mounting differences between these parts?

A: All three parts use identical 16-DIP through-hole packaging (0.300", 7.62mm). No PCB layout or assembly process modifications are required for substitution.