DM74LS73AN Equivalent & Substitute Parts

Part Overview

The DM74LS73AN is a dual JK-type flip-flop logic integrated circuit manufactured by onsemi, housed in a 14-DIP package. This device features two independent 1-bit JK flip-flops with master reset functionality and complementary outputs, operating at a clock frequency of 25 MHz with negative edge triggering. The DM74LS73AN is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support, maintenance, and new design implementations where this component is specified.

Substiute Parts

DM74LS73AN

onsemiIn Stock: 1670DM74LS73AN Datasheet

Current PartRFQ

SN74LS73AN

Texas InstrumentsIn Stock: 13506SN74LS73AN Datasheet

DirectRFQ

SN54LS73AJ

Texas InstrumentsIn Stock: 98743SN54LS73AJ Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the DM74LS73AN is determined by strict alignment of the following critical parameters:

Core Functional Requirements:

• Dual JK-type flip-flop architecture with 1-bit per element configuration
• Complementary output type
• Negative edge trigger mechanism
• Master reset functionality
• 74LS logic series classification

Electrical Compatibility Parameters:

• Supply voltage range: 4.75V ~ 5.25V (or compatible superset range)
• Output current specifications: 400µA (high), 8mA (low)
• Operating temperature range: 0°C ~ 70°C minimum coverage

Physical Compatibility Parameters:

• 14-DIP package format (0.300", 7.62mm pitch)
• Through-hole mounting type
• Pin-compatible footprint

Substitute parts must maintain functional equivalence across all specified parameters. Performance enhancements (higher clock frequency, improved propagation delay) are acceptable provided core electrical and physical specifications remain compatible or exceed the original requirements.

Parameter Comparison

Engineering Selection Recommendations

SN74LS73AN (Texas Instruments) - Primary Direct Substitute

The SN74LS73AN is the recommended primary substitute for the DM74LS73AN. This part maintains identical electrical specifications (supply voltage, output current, operating temperature range) and package format (14-DIP). The SN74LS73AN offers enhanced performance with a 45 MHz clock frequency versus the original 25 MHz, providing operational margin without compromising compatibility. This part is in active production status with ROHS3 compliance certification, ensuring long-term availability and regulatory alignment for new designs and system replacements.

SN54LS73AJ (Texas Instruments) - Extended Temperature Substitute

The SN54LS73AJ provides functional equivalence with extended operating temperature range (-55°C ~ 125°C) compared to the DM74LS73AN (0°C ~ 70°C). This part is suitable for applications requiring broader temperature performance or military-grade specifications. The SN54LS73AJ uses a 14-CDIP package variant and features improved supply voltage tolerance (4.5V ~ 5.5V). Output current specifications differ (4mA versus 8mA low), requiring verification for applications with specific current-sinking requirements. This part maintains active production status with ROHS3 compliance.

Both substitute parts are manufactured by Texas Instruments, a primary 74LS logic series supplier, and maintain the dual JK flip-flop architecture, complementary output configuration, and negative edge triggering required for functional compatibility with the obsolete DM74LS73AN.

Frequently Asked Questions (FAQ)

Q: Can the SN74LS73AN directly replace the DM74LS73AN in existing designs?

A: Yes. The SN74LS73AN maintains identical electrical specifications and 14-DIP package compatibility. Pin configuration, supply voltage requirements (4.75V ~ 5.25V), output current ratings (400µA high, 8mA low), and operating temperature range (0°C ~ 70°C) are equivalent. The enhanced 45 MHz clock frequency provides performance margin without introducing compatibility issues.

Q: What is the difference between the SN74LS73AN and SN54LS73AJ?

A: Both parts provide dual JK flip-flop functionality with complementary outputs and negative edge triggering. Key differences include: (1) Operating temperature range: SN74LS73AN covers 0°C ~ 70°C; SN54LS73AJ covers -55°C ~ 125°C; (2) Supply voltage tolerance: SN74LS73AN accepts 4.75V ~ 5.25V; SN54LS73AJ accepts 4.5V ~ 5.5V; (3) Package variant: SN74LS73AN uses 14-DIP; SN54LS73AJ uses 14-CDIP; (4) Output current low: SN74LS73AN specifies 8mA; SN54LS73AJ specifies 4mA. Select based on temperature requirements and current-sinking specifications of your application.

Q: Are there package compatibility considerations when substituting?

A: The SN74LS73AN uses a standard 14-DIP package (0.300", 7.62mm) identical to the DM74LS73AN and is directly pin-compatible. The SN54LS73AJ uses a 14-CDIP variant, which maintains the same 0.300" pitch and pin count but may have different physical dimensions. Verify PCB footprint compatibility before substitution, particularly for space-constrained layouts.

Q: What is the significance of the 74LS versus 54LS series designation?

A: The 74LS series is commercial-grade logic (0°C ~ 70°C operating range), while the 54LS series is military-grade logic (-55°C ~ 125°C operating range). The SN74LS73AN is appropriate for standard commercial and industrial applications. The SN54LS73AJ is specified for military, aerospace, or extended-temperature industrial environments. Select based on application temperature requirements.

Q: Why is the DM74LS73AN classified as obsolete?

A: The DM74LS73AN is no longer in active production by onsemi. Substitute parts from active manufacturers (Texas Instruments SN74LS73AN or SN54LS73AJ) are recommended for new designs and system replacements to ensure long-term component availability and supply chain continuity.

Q: Are the substitute parts RoHS compliant?

A: Yes. Both the SN74LS73AN and SN54LS73AJ are ROHS3 compliant, meeting current environmental and regulatory requirements for electronic component manufacturing and use.