PCA9545APW,112

Specialized Overview

The PCA9545APW,112 is a quad bidirectional translating switch controlled via the I2C-bus. It fans out an upstream SCL/SDA pair to four downstream pairs (channels). The device supports an operating power supply voltage range of 2.3 V to 5.5 V and allows voltage level translation between 1.8 V, 2.5 V, 3.3 V, and 5 V buses. It features low Ron switches with a maximum on-state resistance of 24 Ohms at 5.5 V. The component supports clock frequencies from 0 Hz to 400 kHz and includes four active LOW interrupt inputs and one active LOW interrupt output. An active LOW reset input allows recovery from stuck bus conditions. The package is TSSOP-20.

Specialized Feature Summary

• Provides four independent bidirectional channels for I2C bus expansion
• Enables voltage level translation between different bus voltages using the VDD pin
• Includes interrupt logic with dedicated inputs per channel and a combined output
• Features an active LOW reset input to clear stuck bus states

Specialized Applications

• Expanding I2C bus capacity in embedded systems
• Connecting multiple I2C devices with address conflicts
• Translating voltage levels between 1.8V/2.5V/3.3V and 5V components

Specialized Procurement Notes

Verify the specific ordering suffix ',112' corresponds to the tube packing method as defined in the NXP datasheet. Confirm the TSSOP-20 package type matches the design requirements. Ensure compatibility with the target I2C controller interface and check for any end-of-life notices or alternative sourcing options if availability is constrained.

Specialized Selection Notes

Select this component when four independent I2C channels are required with voltage translation capabilities. The TSSOP-20 package is suitable for surface mount applications requiring a compact footprint. Consider the interrupt logic and reset functionality if bus fault recovery or event-driven communication is necessary for the system design.

Specialized Part Context

The PCA9545APW,112 belongs to the PCA9545A family of I2C multiplexers and switches. This family includes variants with different packages such as SO20 and HVQFN20. The 'APW' designation specifically indicates the TSSOP-20 plastic thin shrink small outline package version manufactured by NXP Semiconductors.

Specialized Replacement Considerations

Direct replacements within the same family include PCA9545AD (SO20) and PCA9545ABS (HVQFN20). Verify that the substitute package maintains compatible pinout and thermal characteristics for the existing PCB layout.