PCA8575DB,112 Equivalent & Substitute Parts

Part Overview

The PCA8575DB,112 is a 16-bit I/O Expander with I2C interface operating at 400 kHz, manufactured by NXP USA Inc. in a 24-SSOP surface mount package. This component is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production support. The part provides 16 I/O lines with push-pull output configuration, interrupt output capability, and power-on reset (POR) functionality, suitable for applications requiring expanded digital I/O capabilities in embedded systems.

Substiute Parts

PCA8575DB,112

NXP USA Inc.In Stock: 794PCA8575DB,112 Datasheet

Current PartRFQ

PCF8575DB

Texas InstrumentsIn Stock: 1432PCF8575DB Datasheet

DirectRFQ

SX1509BIULTRT

Semtech CorporationIn Stock: 27353SX1509BIULTRT Datasheet

MFR RecommendedRFQ

SX1509QBIULTRT

Semtech CorporationIn Stock: 2173SX1509QBIULTRT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the PCA8575DB,112 is determined by the following critical parameters: 16 I/O lines, I2C interface at 400 kHz clock frequency, interrupt output capability, and surface mount packaging. The substitute parts are grouped into two categories based on package compatibility and product status:

Category 1: Direct Package Equivalent (24-SSOP)

• PCF8575DB (Texas Instruments) maintains identical 24-SSOP packaging and electrical interface specifications, supporting both I2C and SMBus protocols.

Category 2: Enhanced Functionality Alternative (28-QFN)

• SX1509BIULTRT and SX1509QBIULTRT (Semtech Corporation) provide 16 I/O lines with I2C 400 kHz interface in an alternative 28-QFN package. These parts offer extended features including keypad controller and LED output functionality, with active product status and wider voltage supply range (1.425V ~ 3.6V).

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Same Package): PCF8575DB is the appropriate selection when PCB layout and form factor constraints require the 24-SSOP package. Both the PCA8575DB,112 and PCF8575DB are obsolete; however, PCF8575DB maintains higher inventory availability (1407 units) and adds SMBus protocol support. Both parts meet ROHS3 compliance and identical operating temperature specifications.

For New Designs (Active Product Status): SX1509BIULTRT and SX1509QBIULTRT are recommended for new development due to active product status, ensuring long-term availability and supply chain stability. These parts require PCB redesign to accommodate the 28-QFN package but provide extended functionality including keypad controller and LED output features. The lower voltage supply range (1.425V ~ 3.6V) suits low-power applications, though designs operating above 3.6V require the higher voltage tolerance of the 24-SSOP alternatives. Both Semtech variants maintain identical electrical specifications; SX1509BIULTRT offers higher inventory (27259 units).

Frequently Asked Questions (FAQ)

Q: Can PCF8575DB directly replace PCA8575DB,112 without PCB modifications? A: Yes. PCF8575DB is a direct package equivalent in 24-SSOP with identical pinout and electrical interface. No PCB layout changes are required. Both parts are obsolete; verify long-term availability with your supplier.

Q: What are the key differences between the 24-SSOP and 28-QFN substitute options? A: The 24-SSOP options (PCA8575DB,112 and PCF8575DB) maintain identical packaging for direct replacement. The 28-QFN options (SX1509BIULTRT and SX1509QBIULTRT) require PCB redesign but offer active product status, extended features (keypad controller, LED output), and lower voltage supply range (1.425V ~ 3.6V). Current sourcing capability differs: 24-SSOP parts provide 100µA/25mA, while 28-QFN parts provide 8mA/15mA.

Q: Are there voltage supply compatibility concerns when substituting? A: Yes. The original PCA8575DB,112 operates at 2.3V ~ 5.5V. PCF8575DB operates at 2.5V ~ 5.5V (0.2V minimum difference). SX1509 variants operate at 1.425V ~ 3.6V, unsuitable for applications requiring supply voltages above 3.6V. Verify your design's supply voltage range before selecting a substitute.

Q: Which substitute part has the best long-term availability? A: SX1509BIULTRT has the highest current inventory (27259 units) and active product status, providing the best long-term supply chain assurance. PCF8575DB and SX1509QBIULTRT are also available but with lower inventory levels.

Q: Do the substitute parts support the same I2C clock frequency? A: Yes. All substitute parts operate at 400 kHz I2C clock frequency, matching the original PCA8575DB,112 specification.