DM74AS27N Equivalent & Substitute Parts

Part Overview

The DM74AS27N is a NOR Gate IC featuring 3 channels with 3 inputs per channel in a 14-MDIP through-hole package, manufactured by onsemi. This logic component operates within the 74AS series and is classified as obsolete. Due to its obsolete status and limited availability from the original manufacturer, identifying equivalent and substitute parts is essential for design continuity and procurement flexibility.

Substiute Parts

DM74AS27N

onsemiIn Stock: 2381DM74AS27N Datasheet

Current PartRFQ

SN74AS27D

Texas InstrumentsIn Stock: 1514SN74AS27D Datasheet

SimilarRFQ

SN74AS27N

Texas InstrumentsIn Stock: 3586SN74AS27N Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the DM74AS27N is determined by strict equivalence across the following electrical and mechanical parameters:

• Logic function: NOR Gate with identical circuit count (3) and input configuration (3 inputs per channel)
• Electrical specifications: Supply voltage range (4.5V ~ 5.5V), output current ratings (2mA high, 20mA low), input logic levels (0.8V low, 2V high), and propagation delay (5.5ns @ 5V, 50pF)
• Operating temperature range: 0°C ~ 70°C
• Base product series: 74AS

Substitute parts are grouped by package type and mounting technology. The DM74AS27N uses through-hole mounting (14-MDIP). The SN74AS27N (Texas Instruments) provides parametric equivalence with identical through-hole packaging. The SN74AS27D (Texas Instruments) maintains full electrical equivalence but uses surface-mount technology (14-SOIC), requiring design and assembly modifications.

Parameter Comparison

Engineering Selection Recommendations

For direct replacement of the DM74AS27N in through-hole applications, the SN74AS27N (Texas Instruments) is the primary substitute. This part maintains identical electrical parameters, operating temperature range, and through-hole package configuration (14-DIP). The SN74AS27N carries Active product status and ROHS3 compliance, providing superior long-term availability and regulatory alignment compared to the obsolete DM74AS27N.

The SN74AS27D (Texas Instruments) provides full electrical equivalence but requires PCB redesign and assembly process modification due to its surface-mount package (14-SOIC). This option is suitable only when board-level changes are feasible and surface-mount assembly capability is available.

Frequently Asked Questions (FAQ)

Q: Can the SN74AS27N directly replace the DM74AS27N without PCB modifications?

A: Yes. Both parts share identical electrical specifications, operating temperature range, and through-hole package dimensions (14-DIP, 0.300" pitch). Pin-to-pin compatibility is maintained.

Q: What is the primary advantage of selecting the SN74AS27N over the DM74AS27N?

A: The SN74AS27N carries Active product status, ensuring continued availability and supply chain stability. It also meets ROHS3 compliance requirements, whereas the DM74AS27N is classified as obsolete.

Q: Can the SN74AS27D be used as a drop-in replacement?

A: No. The SN74AS27D uses surface-mount packaging (14-SOIC) versus the through-hole configuration (14-DIP) of the DM74AS27N. PCB redesign and surface-mount assembly are required. This substitution is only viable when board-level modifications are acceptable.

Q: Are the electrical characteristics identical across all three parts?

A: Yes. The DM74AS27N, SN74AS27N, and SN74AS27D share identical electrical specifications: supply voltage (4.5V ~ 5.5V), output current ratings (2mA high, 20mA low), input logic levels (0.8V low, 2V high), propagation delay (5.5ns @ 5V, 50pF), and operating temperature range (0°C ~ 70°C).

Q: What packaging considerations apply when selecting a substitute?

A: The DM74AS27N and SN74AS27N both use 14-DIP through-hole packages with 0.300" (7.62mm) pitch, suitable for breadboard and conventional PCB assembly. The SN74AS27D uses 14-SOIC surface-mount packaging with 0.154" (3.90mm) width, requiring surface-mount assembly equipment and techniques.