NXP PCA9546PW 4-Channel I2C Switch

The NXP PCA9546PW is a robust and versatile 4-channel I2C-bus switch with an interrupt logic, designed to provide seamless communication for applications that require multiple I2C devices with the same address to be connected to a single I2C bus. The device comes in a TSSOP-16 (thin shrink small outline package) that is suitable for a wide range of applications in the consumer, industrial, and automotive markets.

The PCA9546PW allows four bidirectional I2C-bus channels to be controlled via a single I2C-bus address, making it an ideal solution for systems that need to switch between different I2C devices or extend the I2C bus range. Each switch channel can be independently enabled or disabled via I2C-bus commands, and the device offers a low on-resistance, ensuring minimal signal distortion during switching.

This I2C switch is designed for a power supply range of 2.3V to 5.5V, making it compatible with both standard and low-voltage I2C-bus devices. Additionally, the PCA9546PW supports hot insertion, which means devices can be added or removed without powering down the system.

The interrupt logic featured in the PCA9546PW is a significant advantage, as it allows the device to report back to the host controller when an interrupt has occurred on any of the downstream I2C devices, without the need for constant polling. This feature can greatly reduce the overhead on the host controller and improve system efficiency.

To ensure reliable operation, the PCA9546PW incorporates power-up with all switch channels deselected and features an active LOW reset input that enables the host to perform a hardware reset. The device's built-in level shifting ensures that each channel can interface with different logic levels, hence providing the necessary flexibility for mixed-voltage systems.

In summary, the NXP PCA9546PW is a high-quality, feature-rich I2C switch that simplifies the design of complex systems with multiple I2C devices, offering both flexibility and efficiency in a compact package.