PCA9518D,118

Specialized Overview

The PCA9518D,118 is a BiCMOS expandable five-channel I2C-bus hub manufactured by NXP Semiconductors. It buffers both data (SDA) and clock (SCL) lines to extend bus capacitance limits beyond the standard 400 pF restriction. The device operates within a supply voltage range of 3.0 V to 3.6 V and supports Standard-mode (0 Hz to 100 kHz) and Fast-mode (0 Hz to 400 kHz) protocols. It features open-drain inputs/outputs, active HIGH enable pins for individual channel control, and four expansion pins for clustering multiple hubs. The component is housed in an SO20 plastic small outline package with 20 leads.

Specialized Feature Summary

• Expandable architecture allowing unlimited bus segmentation via dedicated expansion pins
• Lock-up free operation ensuring stable arbitration and clock stretching across repeaters
• Powered-off high-impedance state preventing current leakage when VDD is below operating thresholds
• 5 V tolerant I/O pins enabling direct interfacing between different voltage domains without level shifters

Specialized Applications

• I2C-bus systems requiring extension beyond standard capacitance limits
• Multi-master configurations needing segment isolation
• System management bus (SMBus) implementations
• Applications requiring powered-off high-impedance protection

Specialized Procurement Notes

Verify the specific ordering suffix '118' against the manufacturer's current catalog to confirm packaging details and availability status. Ensure the selected variant matches the required SO20 package dimensions and lead pitch specifications for PCB footprint compatibility. Cross-reference the RoHS compliance documentation provided in the official datasheet to meet environmental regulatory requirements for the target assembly process.

Specialized Selection Notes

Select this component when system design requires expanding I2C bus capacity beyond 400 pF while maintaining signal integrity. It is suitable for designs needing independent channel enablement via active HIGH inputs. Consider the 3.0 V to 3.6 V supply requirement and ensure the application environment remains within the specified -40 °C to +85 °C temperature range. Verify that the open-drain output configuration aligns with the pull-up resistor strategy of the host bus.

Specialized Part Context

This part belongs to the PCA9518 series of expandable I2C-bus hubs. It serves as a bridge between master controllers and multiple slave segments, effectively creating a tree-like network structure. The device complements other bus interface solutions by providing hardware-based signal buffering and arbitration support without requiring complex software drivers for basic repeater functionality.

Specialized Replacement Considerations

The PCA9518DWG4 is a documented equivalent from Texas Instruments offering similar expandable five-channel hub functionality. Verify pinout compatibility and electrical characteristics before substitution.