PCA9539PWR I/O Expander Equivalent & Substitute Parts

Part Overview

The PCA9539PWR is a 16-bit I/O expander interface circuit manufactured by Texas Instruments, designed for I2C and SMBus communication at 400 kHz. This device is classified as "Not For New Designs," indicating it has been superseded in the manufacturer's product roadmap. Finding equivalent and substitute parts is necessary for ongoing production support, legacy system maintenance, and design flexibility when the primary part faces supply constraints or end-of-life transitions.

Substiute Parts

PCA9539PWR

Texas InstrumentsIn Stock: 3938PCA9539PWR Datasheet

Current PartRFQ

TCA9539PWR

Texas InstrumentsIn Stock: 61089TCA9539PWR Datasheet

DirectRFQ

PCA9539APW,118

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

MFR RecommendedRFQ

PCA9539PW,118

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

MFR RecommendedRFQ

PI4IOE5V9539LEX

Diodes IncorporatedIn Stock: 2991PI4IOE5V9539LEX Datasheet

MFR RecommendedRFQ

XRA1203IG24TR-F

MaxLinear, Inc.In Stock: 10681XRA1203IG24TR-F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the PCA9539PWR is determined by the following critical parameters:

• I/O Count: Must be 16 bits
• Interface Protocol: Must support I2C and/or SMBus at 400 kHz
• Package: Must be 24-TSSOP form factor
• Voltage Supply Range: Must encompass or be compatible with 2.3V ~ 5.5V
• Operating Temperature: Must support -40°C ~ 85°C
• Interrupt Output: Must be present
• Mounting Type: Must be Surface Mount

Four substitute parts meet these criteria with varying degrees of parameter alignment and product status maturity.

Parameter Comparison

Engineering Selection Recommendations

Tier 1 - Direct Substitutes (Highest Compatibility)

TCA9539PWR (Texas Instruments) and PCA9539PW,118 (NXP USA Inc.) are the primary substitutes. Both maintain active product status, support the full I2C/SMBus protocol suite, and preserve the 24-TSSOP package footprint. TCA9539PWR extends the lower voltage supply limit to 1.65V, providing broader operational flexibility. PCA9539PW,118 maintains the original 2.3V lower limit, ensuring drop-in compatibility for designs with this voltage floor. Both are ROHS3 compliant with MSL 1 rating.

Tier 2 - Compatible Substitutes (Parameter Variations)

PCA9539APW,118 (NXP USA Inc.) is functionally equivalent to PCA9539PW,118 but supplied in Tape & Reel packaging rather than Cut Tape. This part is suitable for high-volume production environments. The lower voltage supply extends to 1.65V.

PI4IOE5V9539LEX (Diodes Incorporated) maintains core I2C protocol support at 400 kHz with 16 I/O and 24-TSSOP packaging. Output type and current specifications are not provided in available documentation, requiring design verification before implementation in new applications.

Tier 3 - Limited Compatibility (Significant Parameter Deviation)

XRA1203IG24TR-F (MaxLinear, Inc.) supports I2C and SMBus protocols with 16 I/O at 400 kHz in 24-TSSOP packaging. However, the voltage supply range is restricted to 1.65V ~ 3.6V, which does not encompass the original 5.5V upper limit. The output type is Open Drain rather than Push-Pull, requiring circuit topology adjustments. This part is suitable only for designs operating within the 1.65V ~ 3.6V envelope with Open Drain output compatibility.

All substitute parts maintain ROHS compliance and MSL 1 moisture sensitivity ratings, supporting deployment in standard manufacturing environments.

Frequently Asked Questions (FAQ)

Q: Can TCA9539PWR directly replace PCA9539PWR in existing designs?

A: Yes. TCA9539PWR is manufactured by Texas Instruments and maintains identical I/O count, interface protocol, clock frequency, package form factor, and operating temperature range. The extended lower voltage supply limit (1.65V vs. 2.3V) provides additional operational margin. Pin-to-pin compatibility and functional equivalence are confirmed.

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

A: Both are NXP USA Inc. products with identical electrical specifications. The primary difference is packaging: PCA9539APW,118 is supplied in Tape & Reel format for automated assembly lines, while PCA9539PW,118 is supplied in Cut Tape format. Electrical performance and pin configuration are identical.

Q: Why does XRA1203IG24TR-F have a restricted voltage range?

A: XRA1203IG24TR-F is designed for lower-voltage applications and operates within 1.65V ~ 3.6V. The original PCA9539PWR supports 2.3V ~ 5.5V. XRA1203IG24TR-F is suitable only for designs that do not require 5V operation or higher supply voltages.

Q: What does "Open Drain" output mean for XRA1203IG24TR-F?

A: Open Drain output requires external pull-up resistors to establish high logic levels, differing from the Push-Pull output of the original part. Circuit design modifications are necessary if switching from PCA9539PWR to XRA1203IG24TR-F.

Q: Are all substitute parts ROHS compliant?

A: Yes. All listed substitute parts are ROHS3 compliant or RoHS compliant, meeting environmental and hazardous substance restrictions for commercial and industrial applications.

Q: Which substitute has the best inventory availability?

A: TCA9539PWR has the highest inventory level at 60,988 pieces. XRA1203IG24TR-F follows with 10,600 pieces. PCA9539PW,118 has 3,083 pieces, and PI4IOE5V9539LEX has 2,900 pieces.

Q: Can PI4IOE5V9539LEX be used without additional design verification?

A: PI4IOE5V9539LEX lacks documented specifications for output type and current source/sink ratings. Design verification is required before implementation to confirm compatibility with existing circuit requirements.