N74F20D,623 NAND Gate IC Equivalent & Substitute Parts

Part Overview

The N74F20D,623 is a 2-channel NAND gate IC with 4 inputs per channel in a 14-SOIC surface mount package, manufactured by NXP Semiconductors. This part is classified as obsolete, making substitute components necessary for new designs and ongoing production requirements. The 74F logic family provides standard TTL-compatible switching functionality with specified propagation delays suitable for general-purpose digital logic applications.

Substiute Parts

N74F20D,623

NXP SemiconductorsIn Stock: 1146N74F20D,623 Datasheet

Current PartRFQ

SN74F20D

Texas InstrumentsIn Stock: 1648SN74F20D Datasheet

DirectRFQ

SN74F20DR

Texas InstrumentsIn Stock: 3975SN74F20DR Datasheet

DirectRFQ

SN74S20D

Texas InstrumentsIn Stock: 1156SN74S20D Datasheet

DirectRFQ

SN74F20NSR

Texas InstrumentsIn Stock: 3273SN74F20NSR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the N74F20D,623 is determined by the following critical parameters:

• Logic function: NAND gate with 2 circuits and 4 inputs per circuit
• Supply voltage range: 4.5V ~ 5.5V
• Output current specifications: 1mA high, 20mA low
• Input logic thresholds: 0.8V low, 2V high
• Operating temperature range: 0°C ~ 70°C
• Surface mount packaging in 14-pin SOIC configuration
• RoHS3 compliance and MSL Level 1 rating

Substitute parts must maintain functional equivalence across these parameters. Variations in propagation delay (within the 74F and 74S families) and packaging width do not preclude substitution when electrical characteristics remain compatible.

Parameter Comparison

Engineering Selection Recommendations

For applications currently using the N74F20D,623, the following substitution hierarchy is based on product availability and active manufacturing status:

Primary Recommendation: SN74F20DR (Texas Instruments) This part maintains full electrical equivalence with the original N74F20D,623 across all critical parameters. The SN74F20DR is actively manufactured and available in high volume, making it the preferred choice for new production and redesigns. The 6ns propagation delay is within acceptable tolerance for most 74F-series applications.

Secondary Recommendation: SN74F20NSR (Texas Instruments) This manufacturer-recommended substitute provides identical electrical performance to the N74F20D,623. The SN74F20NSR is actively produced and widely available. Note the package width difference (5.30mm vs. 3.90mm) requires PCB layout verification for space-constrained applications.

Alternative: SN74S20D (Texas Instruments) The SN74S20D operates within a narrower supply voltage range (4.75V ~ 5.25V) compared to the N74F20D,623 (4.5V ~ 5.5V). This part is suitable only for applications with regulated 5V supplies. The 5ns propagation delay matches the original specification. Active production status ensures availability.

End-of-Life Option: SN74F20D (Texas Instruments) This part is in Last Time Buy status and should not be selected for new designs. Existing inventory may be available through authorized distributors for legacy system support only.

Frequently Asked Questions (FAQ)

Q: Can the SN74F20NSR be used as a direct replacement for the N74F20D,623 on existing PCBs?

A: Electrical substitution is valid. However, the SN74F20NSR package width is 5.30mm compared to the original 3.90mm. PCB layout verification is required to confirm the wider package fits within the available footprint space and does not create clearance issues with adjacent components.

Q: What is the difference between the 74F and 74S logic families in these substitutes?

A: Both families are TTL-compatible NAND gate implementations. The 74S series (SN74S20D) operates at higher speed (5ns vs. 6ns propagation delay) but requires a narrower supply voltage range (4.75V ~ 5.25V). The 74F series provides broader voltage tolerance (4.5V ~ 5.5V), making it suitable for less regulated power supplies.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All listed substitute parts—SN74F20D, SN74F20DR, SN74S20D, and SN74F20NSR—are ROHS3 compliant with MSL Level 1 rating, matching the environmental compliance of the original N74F20D,623.

Q: Which substitute has the best long-term availability?

A: The SN74F20DR (Active status, Tape & Reel packaging) and SN74F20NSR (Active status, Tape & Reel packaging) are both actively manufactured by Texas Instruments and represent the most reliable choices for ongoing production requirements. The SN74F20D is in Last Time Buy status and should not be selected for new designs.

Q: Does propagation delay variation affect circuit functionality?

A: The N74F20D,623 specifies 5ns maximum propagation delay. Substitutes SN74F20D, SN74F20NSR, and SN74S20D operate within compatible timing windows. The SN74F20DR specifies 6ns, which is acceptable for most general-purpose logic applications. Design-specific timing analysis is required only for high-speed or time-critical circuits.

Q: Can the SN74S20D be used in applications designed for the 74F series?

A: Functional substitution is valid. The SN74S20D maintains identical logic operation and output current specifications. The narrower supply voltage range (4.75V ~ 5.25V) requires confirmation that the application power supply remains within this window. The faster propagation delay (5ns) is a performance advantage with no compatibility concerns.