PCF8574P,112 Equivalent & Substitute Parts

Part Overview

The PCF8574P,112 is an 8-bit I/O expander with I2C interface operating at 100 kHz, manufactured by NXP USA Inc. in a 16-DIP through-hole package. This part is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production support. The PCF8574P,112 provides push-pull output configuration with interrupt capability and power-on reset (POR) feature, suitable for applications requiring I2C-based I/O expansion in embedded systems.

Key Parameters

Parameter	Value
Number of I/O	8
Interface	I2C
Clock Frequency	100 kHz
Voltage Supply Range	2.5V ~ 6V
Operating Temperature	-40°C ~ 85°C
Output Type	Push-Pull
Current Output Source/Sink	300µA, 25mA
Interrupt Output	Yes
Package Type	16-DIP (0.300", 7.62mm)
Mounting Type	Through Hole
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitution for the PCF8574P,112 is determined by the following critical parameters: I2C interface compatibility, 8-bit I/O configuration, 100 kHz clock frequency, supply voltage range overlap (minimum 2.5V), operating temperature range, interrupt output capability, and RoHS3 compliance. Substitute parts are grouped into two categories based on packaging and mounting technology:

Category 1: Through-Hole DIP Packages (Direct Pin-Compatible Substitutes) Parts maintaining the 16-DIP form factor with through-hole mounting enable direct PCB replacement without layout modification. These include PCF8574N and PCF8574AN from Texas Instruments, both offering identical pinout and electrical interface.

Category 2: Surface-Mount Alternatives (Design-Level Substitutes) Parts with surface-mount packages (16-SOIC, 16-QSOP, 24-TSSOP, 24-WQFN) require PCB redesign but offer enhanced thermal performance and manufacturing efficiency. These include NXP PCF8574T/3,518, Maxim MAX7329AWE+, MAX7329AWE+T, MAX7328AWE+, and onsemi NLVPCA9535 variants.

Category 3: Interface-Variant Substitutes Parts with SMBus interface (MAX1608EEE+, MAX1609EEE+) and 2-Wire interface (MAX7328AWE+) provide functional I/O expansion but require protocol verification during integration.

Parameter Comparison

Part Number	Manufacturer	I/O Count	Interface	Clock (kHz)	Supply (V)	Temp Range (°C)	Output Type	Package	Mounting	Status
PCF8574P,112	NXP USA Inc.	8	I2C	100	2.5~6	-40~85	Push-Pull	16-DIP	Through Hole	Obsolete
PCF8574T/3,518	NXP USA Inc.	8	I2C	100	2.5~6	-40~85	Push-Pull	16-SOIC	Surface Mount	Active
PCF8574N	Texas Instruments	8	I2C	100	2.5~6	-40~85	Push-Pull	16-DIP	Through Hole	Active
PCF8574AN	Texas Instruments	8	I2C	100	2.5~6	-40~85	Push-Pull	16-DIP	Through Hole	Active
MAX7329AWE+	Analog Devices Inc./Maxim	8	I2C	100	2.5~5.5	-40~125	Open Drain	16-SOIC	Surface Mount	Active
MAX7329AWE+T	Analog Devices Inc./Maxim	8	I2C	100	2.5~5.5	-40~125	Open Drain	16-SOIC	Surface Mount	Active
MAX7328AWE+	Analog Devices Inc./Maxim	8	2-Wire	100	2.5~5.5	-40~125	Open Drain	16-SOIC	Surface Mount	Active
MAX1608EEE+	Analog Devices Inc./Maxim	8	SMBus	100	2.7~5.5	-40~85	Open Drain	16-QSOP	Surface Mount	Active
MAX1609EEE+	Analog Devices Inc./Maxim	8	SMBus	100	2.7~5.5	-40~85	Open Drain	16-QSOP	Surface Mount	Active
NLVPCA9535EDTR2G	onsemi	16	I2C	100	1.65~5.5	-55~125	Open Drain	24-TSSOP	Surface Mount	Obsolete
NLVPCA9535EMTTXG	onsemi	8	I2C	100	1.65~5.5	-55~125	Open Drain	24-WQFN	Surface Mount	Obsolete

Engineering Selection Recommendations

For Direct Replacement (Through-Hole Applications) PCF8574N and PCF8574AN from Texas Instruments are pin-compatible direct replacements for the PCF8574P,112. Both parts maintain identical electrical specifications, package geometry, and mounting technology. Both are active products with RoHS3 compliance and equivalent inventory availability. Selection between these two variants depends on packaging preference (tube vs. reel).

For Surface-Mount Redesigns (Active Product Preference) PCF8574T/3,518 from NXP provides the same electrical and functional characteristics as the original part in a surface-mount 16-SOIC package. This part is active and maintains full compatibility with existing firmware and protocol implementations.

For Extended Temperature Range Applications MAX7329AWE+ and MAX7329AWE+T extend the operating temperature range to -40°C ~ 125°C, suitable for industrial and automotive environments. Both are active products with RoHS3 compliance. Note that output type changes from push-pull to open-drain, requiring pull-up resistor configuration in the application circuit.

For SMBus Protocol Requirements MAX1608EEE+ and MAX1609EEE+ provide SMBus interface compatibility at 100 kHz. These parts are active and RoHS3 compliant but require protocol verification to ensure compatibility with existing I2C master implementations, as SMBus includes additional protocol features beyond I2C.

For 2-Wire Interface Applications MAX7328AWE+ supports 2-Wire protocol with extended temperature range (-40°C ~ 125°C). This part is active and RoHS3 compliant but requires interface protocol verification.

Avoid Obsolete Alternatives NLVPCA9535EDTR2G and NLVPCA9535EMTTXG are classified as obsolete. While these parts offer expanded I/O (16-bit for EDTR2G variant) and extended temperature range, their obsolete status makes them unsuitable for new designs requiring long-term supply assurance.

Frequently Asked Questions (FAQ)

Q: Can PCF8574N or PCF8574AN be used as direct replacements for PCF8574P,112? A: Yes. Both Texas Instruments parts are pin-compatible with identical electrical specifications, I2C interface, 100 kHz clock frequency, 8-bit I/O configuration, and 16-DIP package. No circuit modification is required.

Q: What is the difference between push-pull and open-drain output types? A: Push-pull outputs (PCF8574 variants) actively drive both high and low logic levels. Open-drain outputs (MAX7329, MAX7328, MAX1608, MAX1609 variants) require external pull-up resistors to achieve high logic levels. Circuit design must accommodate this difference.

Q: Can MAX7329AWE+ replace PCF8574P,112 in existing designs? A: Electrical substitution is possible due to matching I2C interface, 100 kHz frequency, and 8-bit I/O. However, the output type change from push-pull to open-drain requires circuit modification. Additionally, the surface-mount 16-SOIC package requires PCB redesign.

Q: Why is supply voltage range different between PCF8574 and MAX7329 variants? A: PCF8574 supports 2.5V ~ 6V while MAX7329 supports 2.5V ~ 5.5V. Applications requiring 5.5V ~ 6V operation must use PCF8574 variants. The overlap range (2.5V ~ 5.5V) permits substitution for applications within this window.

Q: Are NLVPCA9535 parts suitable for new designs? A: No. Both NLVPCA9535EDTR2G and NLVPCA9535EMTTXG are classified as obsolete. New designs should use active products such as PCF8574N, PCF8574AN, PCF8574T/3,518, or MAX7329 variants to ensure long-term supply availability and manufacturing support.

Q: What is the difference between PCF8574T/3,518 packaging options? A: PCF8574T/3,518 is supplied in Cut Tape (CT) and Digi-Reel format for automated assembly. This differs from tube packaging used for manual handling. Both formats contain identical parts; packaging selection depends on assembly process requirements.

Q: Can SMBus parts (MAX1608EEE+, MAX1609EEE+) operate with I2C masters? A: SMBus is a subset of I2C with additional protocol features. Basic I2C read/write operations are compatible, but SMBus-specific features (alert response, timeout, packet error checking) may not be supported by standard I2C masters. Protocol verification is required before substitution.

Q: What temperature range should be selected for industrial applications? A: Industrial applications typically require -40°C ~ 125°C operating range. MAX7329AWE+, MAX7329AWE+T, MAX7328AWE+, and onsemi NLVPCA9535 variants meet this requirement. Standard PCF8574 variants are limited to -40°C ~ 85°C.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message