PCA8575D,112 Equivalent & Substitute Parts

Part Overview

The PCA8575D,112 is a 16-bit I/O Expander interface IC operating at 400 kHz I2C protocol, manufactured by NXP USA Inc. 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 part provides 16 I/O lines with push-pull output configuration, interrupt output capability, and power-on reset (POR) feature, suitable for applications requiring expanded digital I/O control via I2C bus.

Substiute Parts

PCA8575D,112

NXP USA Inc.In Stock: 100417PCA8575D,112 Datasheet

Current PartRFQ

PCA8575DB,118

NXP USA Inc.In Stock: 2503PCA8575DB,118 Datasheet

MFR RecommendedRFQ

SX1509QBIULTRT

Semtech CorporationIn Stock: 2173SX1509QBIULTRT Datasheet

MFR RecommendedRFQ

PCA8575DB,118

NXP USA Inc.In Stock: 2503PCA8575DB,118 Datasheet

MFR RecommendedRFQ

SX1509QBIULTRT

Semtech CorporationIn Stock: 2173SX1509QBIULTRT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the PCA8575D,112 is determined by the following critical parameters:

Primary Substitution Criteria:

• Number of I/O lines: 16 (mandatory match)
• Interface protocol: I2C at 400 kHz (mandatory match)
• Interrupt output capability: Yes (mandatory match)
• Operating temperature range: -40°C ~ 85°C (mandatory match)
• Voltage supply compatibility: 2.3V ~ 5.5V or compatible subset

Secondary Compatibility Factors:

• Output type configuration (Push-Pull or Open Drain/Push-Pull dual capability)
• Current output source/sink ratings
• Package form factor and mounting type
• Product status and availability

Two substitute part families are identified:

Group 1: NXP PCA8575 Series (Package Variant) PCA8575DB,118 represents an active production equivalent with identical electrical specifications but different package geometry (24-SSOP vs. 24-SOIC). This substitution requires PCB layout redesign due to package footprint differences.

Group 2: Semtech SX1509 Series (Cross-Manufacturer Alternative) SX1509QBIULTRT provides functional equivalence with 16 I/O, I2C 400 kHz interface, and interrupt output. This part operates at a lower voltage range (1.425V ~ 3.6V) and uses a 28-QFN package, requiring circuit redesign and board layout modification.

Parameter Comparison

Engineering Selection Recommendations

PCA8575DB,118 Selection Criteria: This NXP substitute maintains identical electrical specifications and supply voltage range as the obsolete PCA8575D,112. Both parts are ROHS3 compliant with unlimited moisture sensitivity rating. Selection of PCA8575DB,118 is appropriate when:

• Existing firmware and I2C protocol implementation requires no modification
• PCB redesign for 24-SSOP footprint is feasible
• Active production status and inventory availability are required
• Voltage supply range 2.3V ~ 5.5V is maintained in the application

SX1509QBIULTRT Selection Criteria: This Semtech alternative provides functional I/O expansion capability with identical I2C 400 kHz protocol and 16-bit I/O count. Selection is appropriate when:

• Application voltage supply operates within 1.425V ~ 3.6V range
• Lower output current ratings (8mA source, 15mA sink) satisfy load requirements
• 28-QFN package footprint is compatible with PCB design constraints
• Dual output type capability (Open Drain and Push-Pull) provides design flexibility
• RoHS compliance is required

Both substitute parts maintain active production status and provide long-term component availability compared to the obsolete main part.

Frequently Asked Questions (FAQ)

Q: Can PCA8575DB,118 be used as a direct replacement for PCA8575D,112 without circuit modification?

A: PCA8575DB,118 provides electrical equivalence but requires PCB layout redesign. The 24-SSOP package has different pin spacing and footprint geometry compared to the 24-SOIC package. Pin assignments and electrical function are identical, but physical placement on the circuit board must be modified.

Q: What are the key differences between PCA8575DB,118 and SX1509QBIULTRT?

A: Both parts provide 16 I/O lines with I2C 400 kHz interface and interrupt output. Primary differences are: (1) Voltage supply range—PCA8575DB,118 operates 2.3V ~ 5.5V while SX1509QBIULTRT operates 1.425V ~ 3.6V; (2) Output current ratings—PCA8575DB,118 provides 100µA/25mA while SX1509QBIULTRT provides 8mA/15mA; (3) Package type—24-SSOP versus 28-QFN; (4) Output configuration—Push-Pull only versus Open Drain/Push-Pull dual capability.

Q: Is the SX1509QBIULTRT suitable for 5V applications?

A: No. SX1509QBIULTRT maximum supply voltage is 3.6V, making it unsuitable for applications requiring 5V operation. PCA8575DB,118 supports the full 2.3V ~ 5.5V range and is the appropriate choice for 5V systems.

Q: What is the impact of lower output current ratings on SX1509QBIULTRT?

A: SX1509QBIULTRT provides 8mA source and 15mA sink current compared to PCA8575DB,118 at 100µA source and 25mA sink. Applications requiring higher output current for direct LED driving or logic level shifting may require additional buffer circuitry when using SX1509QBIULTRT.

Q: Are all three parts RoHS compliant?

A: Yes. PCA8575D,112 and PCA8575DB,118 are ROHS3 compliant. SX1509QBIULTRT is RoHS compliant. All parts meet environmental compliance requirements for restricted substance elimination.

Q: What is the moisture sensitivity level for these parts?

A: PCA8575D,112 and PCA8575DB,118 both have MSL 1 (Unlimited), indicating no moisture sensitivity restrictions. SX1509QBIULTRT also has MSL 1 (Unlimited). All parts can be stored and handled without special moisture control measures.