PCA9534DW I/O Expander Equivalent & Substitute Parts

Part Overview

The PCA9534DW is an 8-bit I/O expander with I2C and SMBus interface operating at 400 kHz, manufactured by Texas Instruments in 16-SOIC surface mount package. This device is classified as Last Time Buy, indicating discontinued production. Identifying equivalent and substitute parts is necessary to ensure design continuity and maintain supply chain reliability for applications requiring 8-bit parallel I/O expansion with I2C/SMBus communication.

Substiute Parts

PCA9534DW

Texas InstrumentsIn Stock: 782PCA9534DW Datasheet

Current PartRFQ

TCA9534DWR

Texas InstrumentsIn Stock: 65813TCA9534DWR Datasheet

MFR RecommendedRFQ

MAX7328AWE+

Analog Devices Inc./Maxim IntegratedIn Stock: 724MAX7328AWE+ Datasheet

MFR RecommendedRFQ

MAX7329AWE+

Analog Devices Inc./Maxim IntegratedIn Stock: 1206MAX7329AWE+ Datasheet

MFR RecommendedRFQ

MAX7329AWE+T

Analog Devices Inc./Maxim IntegratedIn Stock: 1106MAX7329AWE+T Datasheet

MFR RecommendedRFQ

PCA9534D,118

NXP USA Inc.In Stock: 4206PCA9534D,118 Datasheet

MFR RecommendedRFQ

PCF8574AT/3,518

NXP SemiconductorsIn Stock: 17634PCF8574AT/3,518 Datasheet

MFR RecommendedRFQ

PCF8574T/3,512

NXP USA Inc.In Stock: 2237PCF8574T/3,512 Datasheet

MFR RecommendedRFQ

PCF8574T/3,518

NXP USA Inc.In Stock: 2285PCF8574T/3,518 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the PCA9534DW are grouped based on the following critical parameters that determine functional compatibility:

Primary Compatibility Criteria:

• 8 I/O lines (fixed requirement)
• I2C interface support (mandatory for protocol compatibility)
• 16-SOIC package form factor (mechanical compatibility)
• Surface mount mounting type
• ROHS3 compliance and REACH unaffected status

Secondary Compatibility Considerations:

• Clock frequency (400 kHz primary, 100 kHz acceptable for lower-speed applications)
• Voltage supply range (2.3V–5.5V primary, 1.65V–5.5V or 2.5V–6V acceptable)
• Output type (Push-Pull primary, Open Drain acceptable with design review)
• Interrupt output capability (present in all listed substitutes)
• Operating temperature range (-40°C ~ 85°C primary, -40°C ~ 125°C acceptable for extended range)

Substitutes are organized into two categories: direct replacements maintaining 400 kHz I2C/SMBus operation, and functional alternatives operating at 100 kHz I2C with design considerations.

Parameter Comparison

Engineering Selection Recommendations

Tier 1 Direct Replacement (Recommended for New Designs):

TCA9534DWR is the primary recommended substitute. Manufactured by Texas Instruments, it maintains 400 kHz I2C operation, Push-Pull output configuration, and identical package form factor. Extended voltage supply range (1.65V–5.5V) provides additional design flexibility. Active product status ensures long-term availability and supply chain stability. ROHS3 compliance and REACH unaffected status match the original specification.

Tier 2 Functional Equivalent (400 kHz I2C/SMBus):

PCA9534D,118 from NXP USA Inc. provides identical electrical and mechanical specifications to the PCA9534DW, including 400 kHz I2C/SMBus interface, Push-Pull output, and matching voltage supply range. Active product status and ROHS3 compliance support production continuity. Tape & Reel packaging differs from the original Tube packaging but maintains component functionality.

Tier 3 Alternative (100 kHz I2C Operation):

PCF8574T/3,512 and PCF8574T/3,518 from NXP USA Inc. operate at 100 kHz I2C frequency with Push-Pull output and extended voltage range (2.5V–6V). These parts are suitable for applications where reduced clock frequency is acceptable. Active product status and ROHS3 compliance are maintained. Moisture Sensitivity Level 2 (1 Year) differs from the original MSL 1 specification.

Tier 4 Alternative (100 kHz I2C, Open Drain Output):

MAX7329AWE+ and MAX7329AWE+T from Analog Devices Inc./Maxim Integrated provide 100 kHz I2C operation with Open Drain output configuration. Extended operating temperature range (-40°C ~ 125°C) supports wider environmental applications. Open Drain output requires pull-up resistor implementation and design review for compatibility with existing circuit topology. Active product status and ROHS3 compliance are confirmed.

MAX7328AWE+ operates at 100 kHz on 2-Wire interface with Open Drain output. Compatibility assessment requires verification of 2-Wire protocol alignment with application requirements.

Frequently Asked Questions (FAQ)

Q: Can TCA9534DWR directly replace PCA9534DW without circuit modifications?

A: Yes. TCA9534DWR maintains identical I/O count (8), interface protocol (I2C), clock frequency (400 kHz), output type (Push-Pull), and package form factor (16-SOIC). The extended voltage supply range (1.65V–5.5V) encompasses the original specification (2.3V–5.5V). No circuit modifications are required.

Q: What are the key differences between 400 kHz and 100 kHz I2C substitutes?

A: Clock frequency determines maximum I2C bus speed. 400 kHz parts (TCA9534DWR, PCA9534D,118) support fast-mode I2C operation. 100 kHz parts (PCF8574 series, MAX7329 series) operate at standard-mode I2C. Applications with timing-critical I2C communication may require 400 kHz operation. Lower-speed applications can use 100 kHz alternatives.

Q: Are Open Drain output substitutes compatible with Push-Pull designs?

A: Open Drain output requires external pull-up resistors and produces different electrical characteristics than Push-Pull output. Circuit topology review is necessary before substitution. Applications designed for Push-Pull output may require redesign to accommodate Open Drain configuration.

Q: Does packaging format affect component functionality?

A: Packaging format (Tube, Tape & Reel, Cut Tape) does not affect electrical or mechanical functionality. All listed substitutes use 16-SOIC surface mount package with identical pin configuration and footprint. Packaging selection depends on assembly process requirements and inventory management.

Q: What is the significance of Moisture Sensitivity Level (MSL) differences?

A: MSL 1 (Unlimited) indicates no moisture sensitivity restrictions. MSL 2 (1 Year) requires controlled storage conditions and limits shelf life to one year after packaging opening. PCF8574 series parts with MSL 2 require stricter moisture control during storage and handling compared to the original PCA9534DW specification.

Q: Are all listed substitutes ROHS3 compliant?

A: Yes. All substitute parts listed maintain ROHS3 compliance and REACH unaffected status, matching the original PCA9534DW environmental certification requirements.