PCA9541D/03,112

Specialized Overview

The PCA9541D/03,112 is a 2-to-1 I2C-bus master selector designed for high-reliability dual-master applications. It operates within an operating power supply voltage range of 2.3 V to 5.5 V and supports clock frequencies from 0 Hz to 400 kHz. The device features active LOW interrupt inputs and outputs, along with an active LOW reset input. It allows voltage level translation between 1.8 V, 2.5 V, 3.3 V, and 5 V buses. All I/O pins are 6.0 V tolerant. The component is housed in an SOIC-16 package and functions within a temperature range of -40 °C to +85 °C.

Specialized Feature Summary

• Provides physical isolation between two upstream masters and downstream slaves to prevent bus lockups during failures.
• Includes internal bus sensor and recovery logic to initialize downstream devices before switching control.
• Supports hot insertion and software identical operation for both connected masters.

Specialized Applications

• High reliability systems requiring dual master redundancy
• Gatekeeper multiplexer on long single bus segments
• Bus initialization or recovery for slave devices lacking hardware reset capabilities

Specialized Procurement Notes

Verify the specific suffix /03 indicates no channel selection at start-up, allowing either master to take control via arbitration. Confirm the SO16 package designation matches the required PCB footprint. Ensure the ordering code includes the full manufacturer part number to distinguish it from similar variants like the PCA9541A series.

Specialized Selection Notes

Select this variant when a neutral power-up state is required for the I2C bus master selection. Compare against the PCA9541A series for updated specifications if available. Ensure external pull-up resistors are included in the design as the device lacks internal pull-ups. Verify that the system voltage levels fall within the supported 1.8 V to 5 V translation range.

Specialized Part Context

This component belongs to the PCA9541 family of I2C bus master selectors manufactured by NXP Semiconductors. It serves as a specialized interface IC designed to manage communication between multiple I2C masters and shared slave devices. The device ensures system continuity by isolating failed masters from the active communication path.

Specialized Replacement Considerations

The PCA9541A is the upgraded version of this component. Verify pin compatibility and register mapping differences before substitution. Check datasheet revisions to ensure functional equivalence regarding interrupt logic and bus recovery sequences.