PCA9545APW Texas Instruments Integrated Circuit (Small Outline Packages) In Stock
PCA9545APW is a 4-channel I2C bus switch with interrupt logic from Texas Instruments. Features active-low enable inputs and bus voltage level translation. From $0.61, in stock, worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Small Outline Packages
- Pin Count
- 20
- Lifecycle
- OBSOLETE
- Datasheet
- PCA9545APW Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $0.6057(MOQ 1)
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 4-channel I2C/SMBus bus switch with individual channel enable control
- Supports voltage level translation between 1.8V, 2.5V, 3.3V, and 5V bus segments
- Active-low interrupt output aggregates interrupt signals from downstream channels
- TSSOP-20 package enables compact board layout in space-constrained designs
Applications
The PCA9545APW is widely used in server and embedded systems to expand I2C bus capacity by isolating multiple downstream segments. It is ideal for multi-sensor platforms, display controllers, and EEPROM arrays where address conflicts must be resolved. The device also suits hot-swap backplane designs and industrial control systems requiring robust bus segmentation.
Specifications
| Pbfree Code | Yes |
| YTEOL | 0 |
| ## PCA9545APW Alternates Showing results | Image |
| Package | Small Outline Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.01 |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for PCA9545APW:
Frequently Asked Questions
What is the PCA9545APW and what does it do?
The PCA9545APW is a 4-channel I2C bus switch from Texas Instruments in a TSSOP-20 package. It allows a single master to communicate with up to four separate downstream I2C bus segments, enabling address conflict resolution and bus isolation in complex system designs.
What supply voltage does the PCA9545APW support?
The PCA9545APW operates from a supply voltage range of 1.65V to 5.5V, supporting standard logic levels of 1.8V, 2.5V, 3.3V, and 5V. This wide range makes it compatible with mixed-voltage systems and modern low-power microcontrollers.
Can the PCA9545APW handle interrupts from downstream devices?
Yes. The PCA9545APW features four active-low interrupt input pins (INT0–INT3) that are logically OR'd and reported to the master through a single interrupt output pin, simplifying interrupt management across multiple downstream I2C bus segments.
What are common alternatives to the PCA9545APW?
Common alternatives include the PCA9546A (also 4-channel, similar pinout), TCA9545A (compatible drop-in), and PCA9548A (8-channel I2C switch for larger designs). All are from Texas Instruments and share similar I2C bus switching functionality with minor differences in channel count or voltage range.
What package does the PCA9545APW come in and where can I buy it?
The PCA9545APW is available in a TSSOP-20 package (PW suffix). It is stocked by major distributors including Digi-Key, Mouser, and Arrow. Pricing starts at approximately $0.61 per unit at volume, with worldwide shipping available through FindMyChip.
Related Guides
SN74LVC14APWR Hex Schmitt-Trigger Inverter: Application Note and Design Guide
Complete design guide for the SN74LVC14APWR hex Schmitt-trigger inverter: thresholds, decoupling, oscillator design, package selection, and common pitfalls.
May 21, 2026
TPS62841DGRR Buck Converter Selection Guide: Ultra-Low 60 nA IQ for Battery-Powered IoT
How to choose the right TPS62841 variant for IoT, wearables, and wireless sensors: quiescent current, voltage range, package, and application examples.
May 21, 2026
TPS54160DGQR Selection Guide: How to Choose a 60V Step-Down Buck Converter
Complete selection guide for the TPS54160DGQR 60V/1.5A step-down converter. Compare specs, alternatives, and sourcing options for industrial and automotive designs.
May 20, 2026
LMV932MM Dual Low-Voltage CMOS Op-Amp: Application Design Guide
Complete application design guide for the LMV932MM dual rail-to-rail CMOS op-amp: supply decoupling, RRIO design rules, stability, and recommended circuits for 1.8V–5.5V battery-powered systems.
May 20, 2026
Why Buy from FindMyChip
About Texas Instruments
Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.
More from Texas Instruments
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $0.6057 | $0.61 |
In Stock · 24h Response · Worldwide Shipping
Response within 24 hours · Worldwide shipping
“FindMyChip sourced our entire STM32 BOM in 48 hours when our usual distributor had 16-week lead times.”