NXP PCA9549D 8-Channel I²C Switch

The PCA9549D is a robust, high-performance 8-channel I²C-bus switch with reset designed by NXP Semiconductors. This integrated circuit is tailored to provide seamless communication for multi-master applications and devices that require a bidirectional 2-wire bus for I²C serial communication.

Each channel of the PCA9549D can be controlled individually via the I²C-bus, enabling connection to eight separate I²C-bus or SMBus segments. This flexibility allows for the expansion of I²C-bus capacity or the isolation of bus segments, which is particularly useful when dealing with I²C devices that have the same address. This makes the PCA9549D an ideal choice for complex systems that require multiple I²C devices to operate in harmony.

The device's internal oscillator ensures a sustained switching between channels without external clock input, while its active LOW reset input allows the system to recover from a situation where one of the downstream I²C-buses is stuck in a low state. This feature is critical for maintaining system integrity and ensuring reliable operation under various conditions.

• Key Features:
• 8 bidirectional translating switches that can isolate I²C-bus segments.
• Channel selection via I²C-bus.
• Active LOW reset input.
• Low standby current.
• Accommodates standard mode, fast mode, and high-speed mode.
• 5 V tolerant inputs.
• No glitch on power-up.
• Supports hot insertion.

With its 5 V tolerant inputs, the PCA9549D can interface with higher voltage levels, making it suitable for mixed-voltage systems. The device ensures no glitch occurs on power-up, preventing any unintended operations during system start-up. Additionally, the PCA9549D supports hot insertion, which allows devices to be added or removed without powering down the system.

Engineered for a wide range of applications, including servers, networking, telecommunications, and consumer electronics, the PCA9549D is available in a 24-pin TSSOP package. Its operational temperature range from -40°C to +85°C ensures reliable performance across various environmental conditions.

Overall, the NXP PCA9549D provides a practical and efficient solution for complex I²C communication challenges, enhancing system design and reliability.