DM74LS90N Equivalent & Substitute Parts

Part Overview

The DM74LS90N is a decade counter integrated circuit manufactured by onsemi, classified as a 4-bit logic counter with negative edge triggering. This device is currently listed as obsolete, which necessitates identification of equivalent and substitute parts for ongoing design requirements and component procurement. The DM74LS90N operates as a single-element decade counter suitable for applications requiring binary-coded decimal (BCD) counting functionality in through-hole DIP packaging.

Substiute Parts

DM74LS90N

onsemiIn Stock: 1224DM74LS90N Datasheet

Current PartRFQ

SN74LS90N

Texas InstrumentsIn Stock: 10266SN74LS90N Datasheet

DirectRFQ

SN74LS90D

onsemiIn Stock: 19389SN74LS90D Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DM74LS90N is determined by strict equivalence across the following critical parameters:

• Logic Function: Decade counter, 4-bit, single element
• Trigger Mechanism: Negative edge triggering
• Reset Type: Asynchronous reset
• Electrical Specifications: Supply voltage 4.75 V ~ 5.25 V, operating temperature 0°C ~ 70°C
• Package Compatibility: 14-DIP form factor with 0.300" (7.62mm) pitch

Substitute parts are categorized as follows:

Direct Equivalent (Pin-Compatible, DIP Package): SN74LS90N maintains identical pinout, electrical characteristics, and through-hole DIP packaging, enabling direct socket replacement.

Functional Equivalent (Different Package): SN74LS90D provides identical logic functionality and electrical performance but uses surface-mount 14-SOIC packaging, requiring PCB redesign for implementation.

Parameter Comparison

Engineering Selection Recommendations

SN74LS90N (Texas Instruments) is the primary substitute for the DM74LS90N. This part maintains identical pinout and through-hole DIP packaging, enabling direct socket replacement without PCB modification. The SN74LS90N is currently in active production status, ensuring long-term availability. The device achieves ROHS3 compliance, meeting modern environmental and regulatory requirements. The count rate specification of 42 MHz exceeds the original 32 MHz, providing performance margin for existing circuit implementations.

SN74LS90D (onsemi) provides functional equivalence with identical logic operation and electrical characteristics. However, this part uses 14-SOIC surface-mount packaging, requiring PCB redesign and assembly process changes. The SN74LS90D is listed as obsolete, limiting its suitability for new long-term procurement strategies.

For applications requiring immediate component replacement with minimal design modification, SN74LS90N is the recommended selection. For new designs or redesign opportunities, surface-mount alternatives should be evaluated based on PCB layout and manufacturing capabilities.

Frequently Asked Questions (FAQ)

Q: Can SN74LS90N directly replace DM74LS90N without PCB modification?

A: Yes. The SN74LS90N maintains identical pinout, electrical specifications, and 14-DIP through-hole packaging. Direct socket replacement is possible without circuit board changes.

Q: What is the difference in count rate between DM74LS90N and SN74LS90N?

A: The DM74LS90N specifies 32 MHz maximum count rate, while SN74LS90N specifies 42 MHz. Both operate within the same supply voltage and temperature ranges. The higher count rate of SN74LS90N provides additional performance margin.

Q: Why is SN74LS90D not recommended as a primary substitute?

A: SN74LS90D uses 14-SOIC surface-mount packaging instead of through-hole DIP. This requires PCB redesign and different assembly processes. Additionally, SN74LS90D is listed as obsolete, limiting future availability.

Q: Are there compliance differences between the substitute parts?

A: SN74LS90N (Texas Instruments) is ROHS3 compliant. Both DM74LS90N and SN74LS90D are RoHS non-compliant. For applications requiring RoHS compliance, SN74LS90N is the appropriate selection.

Q: What supply voltage range applies to all three parts?

A: All three parts operate within 4.75 V to 5.25 V supply voltage range. No voltage adjustment is required when substituting between these devices.

Q: Can SN74LS90D be used in existing through-hole designs?

A: No. SN74LS90D requires surface-mount assembly and cannot be installed in through-hole sockets designed for DIP packages. PCB redesign is mandatory for this substitution.