PCF8575CDWR Equivalent & Substitute Parts

Part Overview

The PCF8575CDWR is a 16-bit I/O expander designed for I2C and SMBus communication at 400 kHz, packaged in a 24-SOIC surface mount configuration. This part is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production requirements. The PCF8575CDWR provides open drain output capability with 10mA and 25mA source/sink current ratings, operating across a 4.5V to 5.5V supply voltage range and -40°C to 85°C temperature range.

Substiute Parts

PCF8575CDWR

Texas InstrumentsIn Stock: 21779PCF8575CDWR Datasheet

Current PartRFQ

PCF8575DBR

Texas InstrumentsIn Stock: 16933PCF8575DBR Datasheet

MFR RecommendedRFQ

NCT5655Y

Nuvoton Technology CorporationIn Stock: 925NCT5655Y Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the PCF8575CDWR is determined by the following core parameters: 16-bit I/O count, I2C/SMBus interface protocol at 400 kHz, interrupt output capability, and operating temperature range of -40°C to 85°C. All substitute parts must maintain these functional specifications.

The PCF8575DBR (Texas Instruments) qualifies as a direct functional substitute with identical I/O count, interface, clock frequency, and temperature range. However, it differs in package type (24-SSOP vs. 24-SOIC), output type (Push-Pull vs. Open Drain), supply voltage range (2.5V ~ 5.5V vs. 4.5V ~ 5.5V), and product status (Active vs. Obsolete).

The NCT5655Y (Nuvoton Technology Corporation) qualifies as a functional substitute with identical I/O count, interface, clock frequency, interrupt output, and temperature range. It differs in package type (24-QFN vs. 24-SOIC), output type (Open Drain, matching the main part), supply voltage range (2.3V ~ 5.5V vs. 4.5V ~ 5.5V), and manufacturer.

Parameter Comparison

Engineering Selection Recommendations

The PCF8575DBR is the manufacturer-recommended substitute from Texas Instruments, maintaining the same base product number (PCF8575) and offering active product status. This part is suitable for applications where the narrower 24-SSOP package footprint is acceptable and where Push-Pull output characteristics are compatible with the circuit design. The expanded supply voltage range (2.5V ~ 5.5V) provides additional design flexibility compared to the original part.

The NCT5655Y provides an alternative from Nuvoton Technology Corporation with active product status and matching open drain output type. This part is suitable for applications where the 24-QFN package footprint is preferred and where the lower minimum supply voltage (2.3V) is beneficial. The QFN package offers reduced board space compared to SOIC and SSOP options.

Both substitute parts maintain ROHS3 compliance and the required operating temperature range. Selection between substitutes depends on package compatibility with existing PCB layouts and output type requirements for the specific application circuit.

Frequently Asked Questions (FAQ)

Q: Can PCF8575DBR directly replace PCF8575CDWR in existing designs?

A: Functional replacement is possible if the circuit design accommodates the differences in package type (24-SSOP vs. 24-SOIC), output type (Push-Pull vs. Open Drain), and supply voltage range (2.5V ~ 5.5V vs. 4.5V ~ 5.5V). PCB layout modifications are required due to different package footprints.

Q: What is the primary difference between PCF8575DBR and NCT5655Y?

A: Both parts provide 16-bit I/O expansion with I2C/SMBus interface at 400 kHz. The PCF8575DBR uses Push-Pull output and 24-SSOP packaging, while the NCT5655Y uses Open Drain output and 24-QFN packaging. The NCT5655Y supports a lower minimum supply voltage (2.3V vs. 2.5V).

Q: Are package changes required when substituting these parts?

A: Yes. The PCF8575CDWR uses 24-SOIC packaging, while PCF8575DBR uses 24-SSOP and NCT5655Y uses 24-QFN. Each package has different pin spacing and footprint dimensions, requiring PCB redesign.

Q: Do all substitute parts maintain the same operating temperature range?

A: Yes. The PCF8575CDWR, PCF8575DBR, and NCT5655Y all operate across -40°C to 85°C, ensuring thermal compatibility in equivalent applications.

Q: Which substitute part maintains the open drain output type of the original?

A: The NCT5655Y maintains open drain output, matching the PCF8575CDWR. The PCF8575DBR uses Push-Pull output, which may require circuit design modifications depending on application requirements.