PCA9545ADWR Equivalent & Substitute Parts

Part Overview

The PCA9545ADWR is a translating switch interface IC manufactured by Texas Instruments, designed for I2C and SMBus applications. This 20-SOIC surface mount component operates across a 2.3V to 5.5V supply voltage range and is classified as a Last Time Buy product. Due to its discontinued status, identifying functionally equivalent substitute parts is essential for design continuity and procurement planning. Substitute parts must maintain compatibility with I2C/SMBus protocols and support equivalent voltage operating ranges within the specified package constraints.

Substiute Parts

PCA9545ADWR

Texas InstrumentsIn Stock: 3202PCA9545ADWR Datasheet

Current PartRFQ

TCA9545APWR

Texas InstrumentsIn Stock: 60229TCA9545APWR Datasheet

MFR RecommendedRFQ

ADP5586ACBZ-00-R7

Analog Devices Inc.In Stock: 2175ADP5586ACBZ-00-R7 Datasheet

MFR RecommendedRFQ

CA91L862A-50IE

Renesas Electronics CorporationIn Stock: 1998CA91L862A-50IE Datasheet

MFR RecommendedRFQ

PCA9545AD,118

NXP USA Inc.In Stock: 2110PCA9545AD,118 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the PCA9545ADWR are evaluated based on the following critical parameters:

Primary Substitution Criteria:

• Interface protocol compatibility (I2C/SMBus support)
• Supply voltage range overlap with 2.3V ~ 5.5V specification
• Surface mount packaging suitable for PCB integration
• RoHS3 compliance and MSL rating consistency
• Functional equivalence as translating switch or bus switch interface

Substitute Classification:

Tier 1 - Direct Functional Equivalent (Same Base Product Family): PCA9545AD,118 maintains the same base product number (PCA9545) and I2C switching functionality with compatible voltage ranges (2.3V ~ 3.6V, 4.5V ~ 5.5V), identical package footprint (20-SOIC), and equivalent compliance certifications.

Tier 2 - Alternative Bus Switch Architecture: TCA9545APWR provides bus switching functionality with 2 x 1:4 circuit configuration, operates across 1.65V ~ 5.5V supply range, and uses 20-TSSOP packaging. This substitute accommodates designs where package height or thermal characteristics differ from SOIC.

Tier 3 - Specialized Interface Solutions: ADP5586ACBZ-00-R7 (Analog Devices) and CA91L862A-50IE (Renesas) represent alternative interface architectures with different package technologies (WLCSP and PBGA respectively) and specialized applications. These are suitable only when design constraints permit package substitution and functional requirements align with their specific interface capabilities.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Recommended Primary Choice): PCA9545AD,118 is the preferred substitute. It maintains identical base product architecture (PCA9545 family), operates within the same voltage specification windows, uses the same 20-SOIC package footprint, and carries Active product status with ROHS3 compliance and MSL-1 rating. PCB layout and firmware integration require no modification.

For Alternative Packaging Requirements: TCA9545APWR serves as a secondary option when thermal management or board space constraints necessitate a smaller package footprint (20-TSSOP vs. 20-SOIC). The extended lower voltage limit (1.65V) provides additional design flexibility. Firmware compatibility and pin mapping must be verified against application requirements.

For Specialized Applications: ADP5586ACBZ-00-R7 and CA91L862A-50IE are suitable only when application-specific requirements (keypad entry expansion, data acquisition interfaces) align with their functional specifications. These substitutes require comprehensive design re-evaluation due to different package technologies and interface protocols.

Compliance Considerations: CA91L862A-50IE does not meet ROHS3 compliance and carries MSL-3 moisture sensitivity rating, making it unsuitable for applications requiring full RoHS compliance or extended storage conditions. This part should be avoided unless legacy system compatibility is mandatory.

Frequently Asked Questions (FAQ)

Q: Can PCA9545AD,118 be used as a direct drop-in replacement for PCA9545ADWR? A: Yes. Both parts share the same base product number (PCA9545), identical 20-SOIC package footprint, compatible I2C interface specifications, and overlapping voltage supply ranges. No PCB layout modifications are required.

Q: What is the primary difference between PCA9545ADWR and TCA9545APWR? A: The TCA9545APWR uses a 20-TSSOP package (smaller footprint, 4.40mm width) versus the 20-SOIC package (7.50mm width) of the PCA9545ADWR. The TCA9545APWR also supports a lower minimum supply voltage (1.65V vs. 2.3V). Pin configuration and functional behavior differ; design verification is required before substitution.

Q: Why is CA91L862A-50IE not recommended as a substitute? A: The CA91L862A-50IE operates at a fixed 3.3V supply voltage (not compatible with the 2.3V ~ 5.5V range), uses a 256-PBGA package (significantly larger and different pinout), does not meet ROHS3 compliance, and carries MSL-3 moisture sensitivity. It represents a different product category (Data Acquisition Interface) rather than a translating switch interface.

Q: Are there any inventory or lead time advantages to selecting substitute parts? A: PCA9545AD,118 shows 2,099 units in stock, while TCA9545APWR has 60,200 units available. The original PCA9545ADWR (Last Time Buy status) has 3,100 units in stock but represents a discontinued product line. For long-term procurement, active product substitutes are recommended.

Q: What compliance certifications should I verify before finalizing a substitute part selection? A: Confirm ROHS3 compliance, MSL rating compatibility with your storage and assembly processes, and REACH compliance status. All recommended substitutes (except CA91L862A-50IE) meet ROHS3 and carry MSL-1 ratings suitable for standard manufacturing environments.

Q: Can ADP5586ACBZ-00-R7 replace PCA9545ADWR in an I2C switching application? A: ADP5586ACBZ-00-R7 supports I2C interface but is designed for keypad entry and I/O expansion applications rather than translating switch functionality. Its 16-WLCSP package and 1.65V ~ 3.6V voltage range differ significantly from the PCA9545ADWR specification. Application-specific functional requirements must be evaluated before considering this substitute.