74ACT11257DBR Equivalent & Substitute Parts

Part Overview

The 74ACT11257DBR is a 4 x 2:1 multiplexer logic integrated circuit manufactured by Texas Instruments in a 20-SSOP surface mount package. This component is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing design support and procurement planning. The part operates on single supply voltage between 4.5V and 5.5V with output current capabilities of 24mA for both high and low states, suitable for standard TTL logic applications requiring multiplexing functionality.

Substiute Parts

74ACT11257DBR

Texas InstrumentsIn Stock: 108874ACT11257DBR Datasheet

Current PartRFQ

74ACT11257DWR

Texas InstrumentsIn Stock: 108974ACT11257DWR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 74ACT11257DBR is determined by the following critical parameters that must remain constant across equivalent parts:

• Functional Circuit: 4 x 2:1 multiplexer configuration with 1 independent circuit
• Electrical Specifications: Single supply voltage range 4.5V ~ 5.5V; output current 24mA high and low
• Operating Temperature Range: -40°C ~ 85°C
• Base Product Number: 74ACT11257 (ensures identical logic family and pinout)
• Compliance Standards: ROHS3 compliance, REACH unaffected status, EAR99 classification

Package variations within the same base product number are acceptable substitutes provided the pinout remains electrically compatible. The primary substitute identified is the 74ACT11257DWR, which maintains all electrical and functional parameters while offering an alternative surface mount package option.

Parameter Comparison

Engineering Selection Recommendations

The 74ACT11257DWR serves as the primary substitute for the obsolete 74ACT11257DBR. Both parts maintain identical electrical specifications, functional performance, and regulatory compliance status. The key distinction is packaging: the substitute uses a 20-SOIC package (0.295" width) compared to the original 20-SSOP package (0.209" width). This package change requires PCB layout modification but does not affect electrical compatibility or performance characteristics.

Selection of the 74ACT11257DWR is supported by its active product status with Texas Instruments, ensuring continued availability and manufacturing support. Both parts carry ROHS3 compliance and REACH unaffected designation, maintaining regulatory alignment for current applications.

Frequently Asked Questions (FAQ)

Q: Can the 74ACT11257DWR directly replace the 74ACT11257DBR without circuit modification?

A: Electrical substitution is complete. However, the package change from 20-SSOP to 20-SOIC requires PCB footprint modification. Pin assignments remain identical, ensuring functional compatibility once layout is updated.

Q: What is the primary reason for seeking a substitute for the 74ACT11257DBR?

A: The 74ACT11257DBR carries obsolete product status. The 74ACT11257DWR maintains active status with the manufacturer, ensuring long-term availability and supply chain stability.

Q: Are there electrical performance differences between these parts?

A: No. Both parts operate identically across all specified parameters: voltage supply range, output current, operating temperature, and logic function. Performance is equivalent.

Q: What are the package dimension implications?

A: The 20-SSOP package measures 0.209" width; the 20-SOIC package measures 0.295" width. The SOIC package is wider and requires corresponding PCB footprint adjustment. Pin pitch and electrical characteristics remain unchanged.

Q: Do both parts meet current regulatory requirements?

A: Yes. Both the 74ACT11257DBR and 74ACT11257DWR are ROHS3 compliant, REACH unaffected, and carry EAR99 classification, meeting current regulatory standards.

Q: Is moisture sensitivity a consideration for these parts?

A: Both parts carry MSL rating 1 (Unlimited), indicating no moisture sensitivity restrictions during storage or handling.