PCA9539PW I/O Expander 16-Bit I2C Interface

Part Overview

The PCA9539PW is a 16-bit I/O expander designed for I2C and SMBus communication at 400 kHz clock frequency. This component is classified as obsolete by Texas Instruments, necessitating identification of active substitute parts for new designs and ongoing production requirements. The part operates across a supply voltage range of 2.3V to 5.5V and is housed in a 24-TSSOP surface mount package.

Substiute Parts

PCA9539PW

Texas InstrumentsIn Stock: 35339PCA9539PW Datasheet

Current PartRFQ

TCA9539PWR

Texas InstrumentsIn Stock: 61089TCA9539PWR Datasheet

MFR RecommendedRFQ

PCA9539PW,118

NXP USA Inc.In Stock: 3096PCA9539PW,118 Datasheet

DirectRFQ

PCA9539APW,118

NXP USA Inc.In Stock: 918PCA9539APW,118 Datasheet

MFR RecommendedRFQ

PI4IOE5V9539LEX

Diodes IncorporatedIn Stock: 2991PI4IOE5V9539LEX Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the PCA9539PW are qualified based on the following electrical and mechanical parameters:

• 16-bit I/O configuration
• I2C interface support at 400 kHz clock frequency
• 24-TSSOP package form factor
• Push-pull output type
• 10mA and 25mA source/sink current capability
• Interrupt output functionality
• Surface mount mounting type
• ROHS3 compliance

Parts meeting these criteria are grouped as direct functional equivalents. Variations in supply voltage range (2.3V ~ 5.5V versus 1.65V ~ 5.5V) do not disqualify substitution when the application operates within the overlapping voltage window.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: TCA9539PWR (Texas Instruments)

TCA9539PWR is the manufacturer-recommended substitute from Texas Instruments. It maintains full electrical and mechanical compatibility with the PCA9539PW while offering active product status and extended supply voltage range (1.65V ~ 5.5V). This part is suitable for applications requiring continued support and availability.

Secondary Recommendation: PCA9539PW,118 (NXP USA Inc.)

PCA9539PW,118 from NXP USA Inc. provides direct functional equivalence with identical electrical specifications and 24-TSSOP packaging. This part maintains the original supply voltage range of 2.3V ~ 5.5V and is actively produced.

Alternative Recommendation: PCA9539APW,118 (NXP USA Inc.)

PCA9539APW,118 offers extended supply voltage range (1.65V ~ 5.5V) with identical I/O configuration and interface specifications. Packaging is supplied as Tape & Reel (TR) format.

Compatibility Note: PI4IOE5V9539LEX (Diodes Incorporated)

PI4IOE5V9539LEX from Diodes Incorporated meets core functional requirements with 16-bit I/O, I2C interface at 400 kHz, and 24-TSSOP packaging. Output type and current specifications are not provided in available documentation. This part is suitable for applications where these parameters are not critical design constraints.

Frequently Asked Questions (FAQ)

Q: Can TCA9539PWR directly replace PCA9539PW in existing designs?

A: Yes. TCA9539PWR maintains identical electrical performance across all specified parameters including I/O count, interface protocol, clock frequency, package form factor, and output characteristics. The extended supply voltage range (1.65V ~ 5.5V) provides additional design flexibility.

Q: What is the difference between PCA9539PW,118 and PCA9539APW,118?

A: Both parts are from NXP USA Inc. and provide 16-bit I2C I/O expansion at 400 kHz. The primary difference is supply voltage range: PCA9539PW,118 operates at 2.3V ~ 5.5V, while PCA9539APW,118 extends to 1.65V ~ 5.5V. Packaging format differs: PCA9539PW,118 is supplied as Cut Tape (CT) & Digi-Reel, while PCA9539APW,118 is Tape & Reel (TR).

Q: Is PI4IOE5V9539LEX compatible with SMBus applications?

A: PI4IOE5V9539LEX supports I2C interface at 400 kHz. SMBus compatibility is not specified in available documentation. Applications requiring explicit SMBus protocol support should select TCA9539PWR, PCA9539PW,118, or PCA9539APW,118.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All listed substitute parts carry ROHS3 compliance certification, matching the original PCA9539PW specification.

Q: What packaging options are available for these substitutes?

A: TCA9539PWR and PCA9539PW,118 are supplied in Cut Tape (CT) & Digi-Reel format. PCA9539APW,118 is supplied as Tape & Reel (TR). PI4IOE5V9539LEX is supplied in Cut Tape (CT) format. All parts use identical 24-TSSOP (0.173", 4.40mm Width) package form factor.