PCA9539DWR Equivalent & Substitute Parts

Part Overview

The PCA9539DWR is a 16-bit I/O Expander with I2C and SMBus interface operating at 400 kHz, manufactured by Texas Instruments in a 24-SOIC package. This component is classified as Obsolete, indicating discontinuation from active production. Finding equivalent substitute parts is necessary to support ongoing system maintenance, design updates, and procurement continuity for applications requiring 16-bit I/O expansion functionality with I2C/SMBus communication protocols.

Substiute Parts

PCA9539DWR

Texas InstrumentsIn Stock: 10657PCA9539DWR Datasheet

Current PartRFQ

TCA9539PWR

Texas InstrumentsIn Stock: 61089TCA9539PWR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the PCA9539DWR is determined by strict alignment of the following critical parameters:

• I/O Count: Must provide 16 I/O lines
• Interface Protocol: Must support I2C and SMBus at 400 kHz
• Interrupt Output: Must include interrupt output capability
• Output Configuration: Must use Push-Pull output type
• Current Specifications: Must support 10mA and 25mA source/sink current
• Supply Voltage Range: Must operate within or encompass the 2.3V ~ 5.5V range
• Operating Temperature: Must support -40°C ~ 85°C range
• Compliance: Must maintain ROHS3 compliance and REACH unaffected status

The TCA9539PWR meets all functional and electrical requirements for substitution. The primary difference is the package format change from 24-SOIC to 24-TSSOP and an extended lower voltage specification (1.65V vs 2.3V minimum).

Parameter Comparison

Engineering Selection Recommendations

The TCA9539PWR is the manufacturer-recommended substitute for the obsolete PCA9539DWR. Both components maintain identical functional specifications for I/O expansion, interface protocols, and electrical performance. The TCA9539PWR offers the advantage of active production status, ensuring long-term availability and supply chain reliability.

The primary consideration for implementation is the package transition from 24-SOIC to 24-TSSOP. This change requires PCB layout modification, as the TSSOP package has a smaller footprint (0.173" vs 0.295" width) and different pin pitch. The TCA9539PWR's extended lower voltage specification (1.65V minimum vs 2.3V) provides additional operational flexibility for low-power applications while maintaining full compatibility with existing 2.3V ~ 5.5V designs.

Both components maintain ROHS3 compliance and REACH unaffected status, supporting regulatory requirements for current manufacturing standards.

Frequently Asked Questions (FAQ)

Q: Can the TCA9539PWR directly replace the PCA9539DWR without design changes?

A: Electrical and functional compatibility is complete. However, the package change from 24-SOIC to 24-TSSOP requires PCB layout redesign. Pin-to-pin functionality is identical, but physical footprint and soldering requirements differ.

Q: What is the primary reason for substitution?

A: The PCA9539DWR is obsolete and no longer manufactured. The TCA9539PWR is the active equivalent from the same manufacturer with identical I/O, interface, and electrical specifications.

Q: Are there any voltage compatibility concerns?

A: No. The TCA9539PWR's extended lower voltage range (1.65V ~ 5.5V) is a superset of the original specification (2.3V ~ 5.5V). All existing designs operating at 2.3V or higher remain fully compatible.

Q: How do the packages differ?

A: The PCA9539DWR uses 24-SOIC packaging (0.295" width), while the TCA9539PWR uses 24-TSSOP packaging (0.173" width). The TSSOP package is smaller and requires different PCB land patterns and soldering techniques.

Q: Are compliance certifications maintained?

A: Yes. Both components are ROHS3 compliant and REACH unaffected, maintaining regulatory compliance for current manufacturing standards.

Q: What are the current output specifications?

A: Both components provide identical push-pull output capability with 10mA and 25mA source/sink current ratings, supporting the same load requirements.