PCA9605D,118

Signal Buffers, Repeaters, Splitters Overview

The PCA9605D,118 is a monolithic CMOS integrated circuit designed for bus buffering in I2C-bus, SMBus, DDC, and PMBus applications. It extends the bus load limit by buffering both SCL and SDA lines, allowing maximum permissible capacitance on either side of the buffer. The device features a unidirectional clock buffer and a bidirectional data buffer with automatic direction control. Operating voltages range from 2.7 V to 5.5 V, supporting Standard-mode, Fast-mode, and Fast-mode Plus (exceeding 1 MHz). Key electrical characteristics include a 30 mA maximum static open-drain pull-down capability, quiescent supply current of 1 µA at 5.5 V, and input hysteresis up to 200 mV. The component is housed in an SO8 plastic small outline package.

Signal Buffers, Repeaters, Splitters Feature Summary

• Simple impedance isolating buffer for 2-wire buses
• Bidirectional data buffer with automatic direction locking
• Enable function allows bus segments to be disconnected
• Hysteresis on inputs provides noise immunity

Signal Buffers, Repeaters, Splitters Applications

• Electronic signs and displays
• Lighting control including architectural and stage lighting
• Building automation systems
• Interfacing standard 3 mA I2C-bus parts to a 30 mA Fm+ bus

Signal Buffers, Repeaters, Splitters Procurement Notes

Verify the ordering suffix '118' corresponds to the specified tape and reel packaging format as defined in the manufacturer's catalog. Confirm that the SO8 package variant matches the required board footprint dimensions. Ensure the procurement source provides valid traceability documentation consistent with NXP Semiconductors standards.

Signal Buffers, Repeaters, Splitters Selection Notes

Select this component when extending I2C bus capacitance limits or isolating bus sections is required. The PCA9605 supports masters on both sides via the DIR pin but does not support slave devices employing clock stretching. Ensure external pull-up resistors are sized appropriately for the desired rise times and operating voltage within the 2.7 V to 5.5 V range.

Signal Buffers, Repeaters, Splitters Part Context

The PCA9605 belongs to NXP's family of simple 2-wire bus buffers. It serves as a hardware solution for managing high-capacitance loads and multi-master configurations where standard I2C specifications are exceeded. The device simplifies system design by handling direction logic internally, reducing the need for complex software control over bus arbitration.

Signal Buffers, Repeaters, Splitters Replacement Considerations

The PCA9525 is a compatible alternative offering similar buffering functionality. Verify compatibility regarding package dimensions and specific electrical parameters such as sink current capabilities before substitution.