PCF8575CDW Equivalent & Substitute Parts

Part Overview

The PCF8575CDW is a 16-bit I/O expander designed for I2C and SMBus communication at 400 kHz, manufactured by Texas Instruments in a 24-SOIC package. This component is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production requirements. The PCF8575CDW provides open-drain output capability with interrupt functionality, suitable for applications requiring expanded digital I/O through a serial interface.

Substiute Parts

PCF8575CDW

Texas InstrumentsIn Stock: 3400PCF8575CDW Datasheet

Current PartRFQ

PCF8575DBR

Texas InstrumentsIn Stock: 16933PCF8575DBR Datasheet

MFR RecommendedRFQ

NCT5655W

Nuvoton Technology CorporationIn Stock: 846NCT5655W Datasheet

MFR RecommendedRFQ

XRA1201IG24TR-F

MaxLinear, Inc.In Stock: 3673XRA1201IG24TR-F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the PCF8575CDW is determined by the following critical parameters:

• I/O Count: 16-bit configuration required
• Interface Protocol: I2C and SMBus compatibility at 400 kHz
• Interrupt Capability: Interrupt output functionality must be present
• Package Compatibility: Physical form factor and pin count (24-pin packages)
• Supply Voltage Range: Operating voltage window must accommodate system requirements
• Output Configuration: Open-drain or push-pull output types
• Product Status: Active status preferred for long-term availability

The substitute parts listed below maintain functional equivalence through matching I/O count, interface protocol, and interrupt capability. Package variations (SOIC, SSOP, TSSOP) represent different physical implementations of the same logical function, with trade-offs in board space and thermal characteristics.

Parameter Comparison

Engineering Selection Recommendations

PCF8575DBR (Texas Instruments, Active Status): Direct functional equivalent from the same manufacturer with identical I/O count, interface protocol, and operating temperature range. Supply voltage range is expanded to 2.5V ~ 5.5V, providing greater flexibility. Package change from 24-SOIC to 24-SSOP reduces board footprint. Output type transitions from open-drain to push-pull, which may require circuit topology review. Recommended for designs requiring Texas Instruments continuity and active product support.

NCT5655W (Nuvoton Technology, Active Status): Functionally equivalent 16-bit I/O expander with I2C/SMBus 400 kHz interface and open-drain output matching the original PCF8575CDW output configuration. Supply voltage range extends to 2.3V ~ 5.5V. Package format is 24-TSSOP, offering reduced board space compared to SOIC. Includes LED output feature not present in the original part. ROHS3 compliant. Suitable for applications prioritizing open-drain output preservation and lower supply voltage operation.

XRA1201IG24TR-F (MaxLinear, Inc., Active Status): Functionally equivalent 16-bit I/O expander with I2C/SMBus 400 kHz interface and interrupt output capability. Supply voltage range is 1.65V ~ 3.6V, restricting use to lower-voltage systems and incompatible with standard 5V logic levels. Package format is 24-TSSOP. RoHS compliant. Selection of this part requires verification that system supply voltage remains within the 1.65V ~ 3.6V window and that all interfacing components operate at this voltage level.

All substitute parts maintain ROHS and REACH compliance status equivalent to or exceeding the original PCF8575CDW specification.

Frequently Asked Questions (FAQ)

Q: Can PCF8575DBR directly replace PCF8575CDW in existing designs?

A: PCF8575DBR maintains functional equivalence in I/O count, interface protocol, clock frequency, and operating temperature. The primary design consideration is the output type change from open-drain to push-pull. If the circuit design relies on open-drain characteristics (such as wired-OR configurations), circuit modification is required. Package change from 24-SOIC to 24-SSOP requires PCB layout adjustment.

Q: What is the key difference between NCT5655W and PCF8575CDW?

A: Both parts provide 16-bit I/O expansion with I2C/SMBus 400 kHz interface and open-drain output. NCT5655W extends the minimum supply voltage to 2.3V and includes LED output capability. The package footprint is smaller (24-TSSOP vs. 24-SOIC). Functional compatibility is maintained for standard I/O expansion applications.

Q: Is XRA1201IG24TR-F suitable for 5V systems?

A: No. XRA1201IG24TR-F operates within 1.65V ~ 3.6V supply range and is not compatible with standard 5V logic systems. This part is restricted to low-voltage applications. Use only when system design operates entirely within the 1.65V ~ 3.6V voltage window.

Q: How do package differences affect substitution?

A: SOIC, SSOP, and TSSOP packages differ in physical dimensions and board footprint. SOIC (0.295" width) is the largest; SSOP (0.209" width) is intermediate; TSSOP (0.173" width) is the smallest. Package selection affects PCB layout, thermal dissipation, and assembly process compatibility. Verify that the selected package is compatible with your manufacturing equipment and thermal requirements.

Q: Are all substitute parts RoHS compliant?

A: Yes. PCF8575DBR and NCT5655W are ROHS3 compliant. XRA1201IG24TR-F is RoHS compliant. All parts meet environmental compliance requirements equivalent to or exceeding the original PCF8575CDW.

Q: What is the primary reason for substitution?

A: PCF8575CDW is classified as obsolete. Substitute parts with active product status (PCF8575DBR, NCT5655W, XRA1201IG24TR-F) ensure long-term availability, manufacturing support, and supply chain continuity for new designs and production requirements.