PCA9512ADP,118

Signal Buffers, Repeaters, Splitters Overview

The PCA9512ADP,118 is a hot swappable I2C-bus and SMBus buffer in an 8-lead TSSOP package. It provides bidirectional buffering for SDA and SCL lines to increase fan-out and prevent bus corruption during live board insertion. The device features two dedicated supply voltage pins (VCC and VCC2) supporting level shifting between 3.3 V and 5 V systems within a 2.7 V to 5.5 V operating range. It includes built-in ΔV/Δt rise time accelerators with a 0.6 V threshold, 1 V precharge circuitry, and an ACC pin to disable accelerators. Operating temperatures range from -40 °C to +85 °C.

Signal Buffers, Repeaters, Splitters Feature Summary

• Bidirectional buffering isolates backplane and card capacitances to prevent signal corruption during hot swapping.
• Dual supply architecture enables level translation between 3.3 V and 5 V systems while maintaining optimal noise margins.
• Integrated ΔV/Δt rise time accelerators enhance signal slew rates, with hardware disable capability via the ACC pin.

Signal Buffers, Repeaters, Splitters Applications

• cPCI, VME, and AdvancedTCA multipoint backplane cards requiring live insertion or removal
• Level translation interfaces between 5 V backplanes and 3.3 V peripheral cards
• Systems requiring isolation of high parasitic capacitance on I/O cards

Signal Buffers, Repeaters, Splitters Procurement Notes

Verify the specific ordering suffix '118' corresponds to the reel packing method required for your assembly line. Confirm that the TSSOP8 package dimensions align with your PCB footprint design rules. Ensure the component temperature rating meets your system's operational environment requirements before finalizing procurement.

Signal Buffers, Repeaters, Splitters Selection Notes

Select this part when dual-supply level shifting is required alongside hot swap protection. The PCA9512A supports both Standard-mode and Fast-mode I2C standards up to 400 kHz. Consider the ACC pin functionality if your system requires disabling rise time accelerators for lightly loaded buses to minimize power consumption or signal overshoot.

Signal Buffers, Repeaters, Splitters Part Context

This component belongs to the PCA9512A family of level-shifting bus buffers. The ADP suffix specifically denotes the TSSOP8 plastic thin shrink small outline package variant. Other family members include the PCA9510A through PCA9514A, which offer varying feature sets such as different rise time accelerator thresholds or ready outputs.

Signal Buffers, Repeaters, Splitters Replacement Considerations

Direct replacements within the same package and feature set are limited due to specific level-shifting capabilities. Verify compatibility with PCA9512AD variants if SO8 packaging is acceptable. Cross-referencing with PCA9511A or PCA9513A may be necessary if specific features like READY outputs or different accelerator thresholds are required.

Signal Buffers, Repeaters, Splitters FAQ

How does the PCA9512A handle bus contention during card insertion?

Control circuitry prevents the backplane from connecting to the card until a stop bit or bus idle condition occurs, ensuring no bus contention arises during the connection process.

What is the function of the ACC pin?

The ACC pin is a digital input that enables or disables the rise time accelerators. Driving it to VCC2 enables normal operation, while driving it to GND turns off the accelerators for lightly loaded systems.

Can the PCA9512A operate with unequal supply voltages?

Yes, either VCC or VCC2 may be powered first, and they can have different voltage levels within the 2.7 V to 5.5 V range, allowing for flexible level shifting configurations.