PCF8575CPWR I/O Expander Equivalent & Substitute Parts

Part Overview

The PCF8575CPWR is a 16-bit I/O expander interface circuit manufactured by Texas Instruments, designed for I2C and SMBus communication at 400 kHz. The device features open drain output configuration with 10mA source and 25mA sink current capability, operating across a 4.5V to 5.5V supply range. The PCF8575CPWR is classified as obsolete, necessitating identification of active equivalent and substitute components for new designs and ongoing production requirements.

Key Parameters

Parameter	PCF8575CPWR
Number of I/O	16
Interface	I2C, SMBus
Clock Frequency	400 kHz
Voltage Supply Range	4.5V ~ 5.5V
Output Type	Open Drain
Current Output Source/Sink	10mA, 25mA
Operating Temperature	-40°C ~ 85°C
Package	24-TSSOP
Product Status	Obsolete
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitution eligibility for the PCF8575CPWR is determined by the following critical parameters: 16 I/O count, I2C/SMBus interface support, 400 kHz clock frequency, 24-TSSOP package compatibility, and output configuration. Parts meeting these core electrical and mechanical specifications are classified as direct substitutes. Secondary considerations include supply voltage range compatibility, output current ratings, and operating temperature range. Parts with reduced supply voltage minimums (below 4.5V) or different output types (push-pull versus open drain) remain functionally compatible but require circuit design verification for the specific application.

Parameter Comparison

Part Number	Manufacturer	I/O Count	Interface	Clock Frequency	Supply Voltage	Output Type	Current Source/Sink	Temperature Range	Package	Status
PCF8575CPWR	Texas Instruments	16	I2C, SMBus	400 kHz	4.5V ~ 5.5V	Open Drain	10mA, 25mA	-40°C ~ 85°C	24-TSSOP	Obsolete
PCF8575PWR	Texas Instruments	16	I2C, SMBus	400 kHz	2.5V ~ 5.5V	Push-Pull	1mA, 25mA	-40°C ~ 85°C	24-TSSOP	Active
MAX7311AUG+	Analog Devices Inc./Maxim Integrated	16	I2C, SMBus	400 kHz	2V ~ 5.5V	Push-Pull	31mA, 43mA	-40°C ~ 125°C	24-TSSOP	Active
MAX7311AUG+T	Analog Devices Inc./Maxim Integrated	16	I2C, SMBus	400 kHz	2V ~ 5.5V	Push-Pull	31mA, 43mA	-40°C ~ 125°C	24-TSSOP	Active
NCT5655Y	Nuvoton Technology Corporation	16	I2C, SMBus	400 kHz	2.3V ~ 5.5V	Open Drain	Not specified	-40°C ~ 85°C	24-QFN (4x4)	Active
PCA9535CPW,118	NXP USA Inc.	16	I2C, SMBus	400 kHz	2.3V ~ 5.5V	Open Drain	10mA, 25mA	-40°C ~ 85°C	24-TSSOP	Active
PCA9535ECDTR2G	onsemi	16	I2C, SMBus	100 kHz	1.65V ~ 5.5V	Open Drain	25mA	-55°C ~ 125°C	24-TSSOP	Obsolete
PI4IOE5V9535LEX	Diodes Incorporated	16	I2C	400 kHz	2.3V ~ 5.5V	Not specified	Not specified	-40°C ~ 85°C	24-TSSOP	Active
PI4IOE5V9555LE	Diodes Incorporated	16	I2C	400 kHz	2.3V ~ 5.5V	Not specified	Not specified	-40°C ~ 85°C	24-TSSOP	Active
PI4IOE5V9555LEX	Diodes Incorporated	16	I2C	400 kHz	2.3V ~ 5.5V	Not specified	Not specified	-40°C ~ 85°C	24-TSSOP	Active
XRA1201IG24TR-F	MaxLinear, Inc.	16	I2C, SMBus	400 kHz	1.65V ~ 3.6V	Not specified	Not specified	-40°C ~ 85°C	24-TSSOP	Active

Engineering Selection Recommendations

Direct Substitutes (Highest Compatibility)

PCA9535CPW,118 from NXP USA Inc. provides the closest electrical and mechanical match to the PCF8575CPWR. Both devices feature 16 I/O, I2C/SMBus interface at 400 kHz, open drain output configuration with identical 10mA source and 25mA sink current ratings, 24-TSSOP package, and -40°C to 85°C operating temperature range. The PCA9535CPW,118 is active and ROHS3 compliant, making it the primary recommendation for direct replacement in existing designs.

Alternative Active Substitutes

PCF8575PWR from Texas Instruments maintains the same manufacturer lineage and package format. The primary differences are push-pull output configuration and expanded supply voltage range (2.5V to 5.5V). This part is active and suitable for applications where push-pull output is acceptable.

MAX7311AUG+ and MAX7311AUG+T from Analog Devices Inc./Maxim Integrated offer enhanced performance with higher output current capability (31mA source, 43mA sink), extended operating temperature range (-40°C to 125°C), and lower minimum supply voltage (2V). Both are active and ROHS3 compliant. These parts are appropriate for applications requiring higher current drive or wider temperature operation.

Package Variant Consideration

NCT5655Y from Nuvoton Technology Corporation provides functional equivalence with 16 I/O, I2C/SMBus interface at 400 kHz, and open drain output. The device uses 24-QFN (4x4) package instead of 24-TSSOP, requiring PCB layout modification. This part is active and ROHS3 compliant.

Limited Compatibility Substitutes

PI4IOE5V9535LEX and PI4IOE5V9555LEX from Diodes Incorporated meet core I/O and frequency requirements but specify I2C interface only (SMBus not confirmed) and do not provide output type or current specifications. These parts are active but require application-level verification.

PCA9535ECDTR2G from onsemi is classified as obsolete and operates at reduced clock frequency (100 kHz), limiting its suitability for 400 kHz applications.

XRA1201IG24TR-F from MaxLinear, Inc. operates at reduced supply voltage range (1.65V to 3.6V), incompatible with the original 4.5V to 5.5V specification.

Frequently Asked Questions (FAQ)

Q: Can PCF8575PWR directly replace PCF8575CPWR in existing circuits?

A: PCF8575PWR is electrically compatible in terms of I/O count, interface protocol, and package. The primary difference is output configuration: PCF8575PWR uses push-pull output versus open drain in the original. If the circuit design relies on open drain characteristics (such as pull-up resistor configuration), push-pull output may cause functional issues. Supply voltage range is also expanded (2.5V minimum versus 4.5V), which is beneficial for lower voltage applications.

Q: What is the significance of open drain versus push-pull output?

A: Open drain output requires external pull-up resistors to establish high logic levels and is commonly used in multi-master I2C systems. Push-pull output actively drives both high and low logic levels without external resistors. Substituting push-pull for open drain may require circuit redesign if pull-up resistors are already present, potentially causing excessive current draw.

Q: Is the NCT5655Y a suitable replacement despite the different package?

A: NCT5655Y provides functional equivalence with identical I/O count, interface, and clock frequency. The 24-QFN (4x4) package differs from the original 24-TSSOP, requiring PCB layout modification and different soldering procedures. Electrical performance is equivalent, making it suitable only if PCB redesign is feasible.

Q: Why do some substitute parts not specify output current ratings?

A: Diodes Incorporated PI4IOE5V series parts do not provide output source/sink current specifications in the available data. This represents incomplete technical documentation rather than reduced capability. Application-level verification with manufacturer datasheets is required before selection.

Q: Can parts with lower clock frequency (100 kHz) substitute for 400 kHz applications?

A: PCA9535ECDTR2G operates at 100 kHz, which is insufficient for applications requiring 400 kHz I2C communication speed. This part is not suitable for direct substitution in 400 kHz systems.

Q: What is the impact of extended operating temperature range in MAX7311 devices?

A: MAX7311AUG+ and MAX7311AUG+T extend the upper operating temperature to 125°C compared to 85°C in the original. This provides additional thermal margin for high-temperature environments but does not affect functionality in standard temperature applications. The extended range is a performance enhancement, not a limitation.

Q: Are all substitute parts ROHS3 compliant?

A: All listed substitute parts are ROHS3 compliant except XRA1201IG24TR-F, which is specified as RoHS Compliant without ROHS3 designation. For applications requiring ROHS3 certification, XRA1201IG24TR-F should be avoided.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message