PCA9509DP/DG,118

Signal Buffers, Repeaters, Splitters Overview

The PCA9509DP,118 is a level translating I2C-bus/SMBus repeater manufactured by NXP Semiconductors. It enables low-voltage processors to interface with standard I2C or SMBus I/O devices. The device provides bidirectional buffering for SDA and SCL lines, supporting a maximum clock frequency of 400 kHz. Port A operates at 1.35 V to VCC(B) - 1.0 V, while Port B supports 3.0 V to 5.5 V. It features an active HIGH enable input, open-drain inputs/outputs, and high-impedance pins when unpowered. The component is housed in an 8-lead TSSOP package (SOT505-1) and operates within an ambient temperature range of -40 °C to +85 °C.

Signal Buffers, Repeaters, Splitters Feature Summary

• Bidirectional buffer isolates capacitance and allows up to 400 pF on port B
• Voltage level translation from port A to port B without external pull-up resistors on the lower voltage side
• Lock-up free operation with internal current sensing mechanism

Signal Buffers, Repeaters, Splitters Applications

• Level translating I2C-bus/SMBus repeater with two voltage supplies
• Enabling processor low voltage 2-wire serial bus to interface with standard I2C-bus or SMBus I/O
• Extending I2C-bus by providing bidirectional buffering for data and clock lines

Signal Buffers, Repeaters, Splitters Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm the exact package type and tape-and-reel specifications. Ensure that the voltage requirements for both Port A and Port B align with your system design before procurement. Cross-reference the RoHS compliance status as indicated in the datasheet.

Signal Buffers, Repeaters, Splitters Selection Notes

Select this component when interfacing low-voltage logic (down to 1.35 V) with standard 3.3 V or 5 V I2C/SMBus buses. Ensure the application does not require Port A voltages below 1.35 V or Port B voltages below 3.0 V; if so, consider the PCA9509A variant. Verify that the system ground offset remains within specified limits to prevent lock-up conditions.

Signal Buffers, Repeaters, Splitters Part Context

The PCA9509 series includes variants such as PCA9509D (SO8), PCA9509DP (TSSOP8), and PCA9509GM (XQFN8). The DP suffix specifically denotes the Thin Shrink Small Outline Package (TSSOP8). All variants share identical electrical characteristics and functionality, differing only in physical packaging dimensions and mounting style.

Signal Buffers, Repeaters, Splitters Replacement Considerations

PCA9509A is documented as a drop-in replacement for applications where Port A VCC(A) is less than 1.35 V or Port B VCC(B) is less than 3.0 V.