PCA9534DBR I/O Expander Equivalent & Substitute Parts

Part Overview

The PCA9534DBR is an 8-bit I/O expander designed for I2C and SMBus communication at 400 kHz, housed in a 16-SSOP package. This component is classified as obsolete, necessitating identification of active equivalent parts for new designs and ongoing production requirements. The part operates across a supply voltage range of 2.3V to 5.5V and supports push-pull output configuration with interrupt capability.

Substiute Parts

PCA9534DBR

Texas InstrumentsIn Stock: 2799PCA9534DBR Datasheet

Current PartRFQ

TCA9534PWR

Texas InstrumentsIn Stock: 165243TCA9534PWR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the PCA9534DBR is determined by the following critical parameters:

• I/O Configuration: 8-bit I/O expander functionality
• Communication Protocol: I2C interface at 400 kHz clock frequency
• Output Architecture: Push-pull output type with 10mA and 25mA source/sink capability
• Interrupt Support: Presence of interrupt output functionality
• Supply Voltage Compatibility: Operating voltage range must accommodate system requirements
• Package Type: Surface mount configuration with SSOP or compatible package footprint
• Environmental Compliance: ROHS3 compliance and MSL rating

The TCA9534PWR qualifies as a manufacturer-recommended substitute based on matching I/O count, interface protocol, output type, current ratings, clock frequency, and environmental compliance. The primary distinction is the package format transition from 16-SSOP to 16-TSSOP and the expanded lower supply voltage limit.

Parameter Comparison

Engineering Selection Recommendations

The TCA9534PWR is the manufacturer-recommended substitute for the obsolete PCA9534DBR. Both components maintain identical functional specifications for I/O count, interface protocol, output configuration, and current ratings. The TCA9534PWR offers the advantage of active product status, ensuring continued availability and supply chain reliability.

The primary design consideration is the package transition from 16-SSOP to 16-TSSOP. While both are surface-mount packages with different physical dimensions, PCB layout modifications are required to accommodate the TCA9534PWR's smaller footprint (0.173" versus 0.209" width). The TCA9534PWR's extended lower supply voltage limit (1.65V versus 2.3V) provides additional operational flexibility for low-power applications.

Both parts maintain ROHS3 compliance and unlimited moisture sensitivity rating, ensuring compatibility with current manufacturing and environmental standards.

Frequently Asked Questions (FAQ)

Q: Can the TCA9534PWR directly replace the PCA9534DBR without PCB modifications?

A: Functional compatibility is confirmed; however, package footprint differences require PCB layout changes. The TCA9534PWR uses 16-TSSOP packaging with a 0.173" width compared to the PCA9534DBR's 16-SSOP with 0.209" width. Existing PCB designs must be updated to accommodate the different pin spacing and package dimensions.

Q: Are the I2C communication protocols identical between these parts?

A: Both components support I2C communication at 400 kHz clock frequency. The PCA9534DBR additionally supports SMBus protocol, while the TCA9534PWR supports I2C. I2C compatibility is maintained, ensuring software and firmware interfaces remain unchanged.

Q: What is the significance of the supply voltage range difference?

A: The PCA9534DBR operates from 2.3V to 5.5V, while the TCA9534PWR operates from 1.65V to 5.5V. The TCA9534PWR's lower minimum voltage enables operation in ultra-low-power applications. Both ranges encompass standard 3.3V and 5V system voltages.

Q: Are there any differences in output current capabilities?

A: Output source and sink current specifications are identical at 10mA and 25mA for both components. Load driving capability remains unchanged in substitution.

Q: What is the impact of the obsolete status of the PCA9534DBR?

A: Obsolete status indicates discontinued manufacturing. The TCA9534PWR, with active product status, ensures long-term availability, supply chain continuity, and access to current manufacturing batches with verified compliance documentation.