NXP Semiconductors PCA9514D,112

Overview

PCA9514D,112 from NXP Semiconductors (formerly Philips Semiconductors) is a hot-swappable I²C and SMBus bus buffer IC designed for backplane-to-card isolation in live-insertion systems. It provides bidirectional SDA/SCL buffering with 0.8 V rise-time accelerator threshold, 2.7–5.5 V supply operation, 400 kHz max clock frequency, and open-drain READY output indicating connection status - deployed in CompactPCI, VME, and AdvancedTCA card-edge interfaces.

For engineers reviewing the PCA9514D,112 datasheet, PCA9514D,112 pinout, PCA9514D,112 application, or PCA9514D,112 equivalent, key selection criteria include ENABLE-controlled low-current shutdown (<200 µA), dynamic offset voltage ≤150 mV, 5.5 V tolerant I/Os, and compatibility with I²C standard/fast mode and SMBus specifications - critical for multi-point backplane reliability under live insertion.

Technical Context

The PCA9514D,112 implements a dynamic offset driver architecture enabling series/parallel cascading with other PCA951x devices (excluding PCA9515/16/17 B-side static-offset I/Os). Its STOP-bit-and-bus-idle detection circuit enforces a minimum 50–250 µs idle period before connecting backplane and card sides, preventing bus contention during hot-swap events.

Rise-time acceleration activates at 0.8 V input threshold with 2 mA transient pull-up current, improving noise margin over earlier PCA9510/11 variants. The device supports clock stretching and multi-master arbitration while maintaining high-impedance SDA/SCL pins at VCC = 0 V and tolerating 5.5 V on all I/Os regardless of supply voltage.

Key Specifications

Pinout & Package

PCA9514D,112 is housed in an 8-pin plastic SO (SO8) package per drawing SOT96-1, 3.9 mm body width, lead pitch 1.27 mm, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I²C bus buffering applications.

Compared with PCA9513D,112, PCA9514D,112 omits the 92 µA backplane pull-up current source - simplifying biasing in non-PICMG systems. Versus TCA9514ADGKR, it shares identical functionality but lacks TI's updated ESD rating and long-term supply assurance, making the latter preferable for production ramp and extended lifecycle programs.

Availability

PCA9514D,112 is available at Aetrix Electronics and suitable for CompactPCI, VME, and AdvancedTCA systems requiring stable component supply, live-insertion reliability, and I²C/SMBus signal integrity across mixed-voltage domains.

Supply support for PCA9514D,112 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader delivering secure, scalable solutions for automotive, industrial, IoT, and communication infrastructure markets.

The PCA9514D,112 belongs to NXP's legacy I²C bus buffer family, engineered specifically for hot-swap-capable multi-point backplane architectures in carrier-grade telecom and industrial computing platforms.

FAQ

What is the primary function of the PCA9514D,112 in an I²C system?

The PCA9514D,112 acts as a hot-swappable bidirectional I²C/SMBus buffer that isolates backplane and card-side capacitance, preventing bus corruption during live insertion. It connects SDAIN/SDAOUT and SCLIN/SCLOUT only after detecting a STOP condition or bus idle period, ensuring reliable operation in CompactPCI and VME systems. The PCA9514D,112 uses dynamic offset drivers and 0.8 V rise-time acceleration to maintain signal integrity across varying loads.

Does the PCA9514D,112 support I²C fast-mode operation at 400 kHz?

Yes, the PCA9514D,112 supports full I²C fast-mode operation up to 400 kHz, meeting timing requirements for tLOW, tHIGH, tr, and tf across its 2.7–5.5 V supply range. Its propagation delays (tPLH ≤20 ns, tPHL ≤380 ns at 100 pF) and 2 mA rise-time acceleration ensure compliance with fast-mode rise-time constraints. The PCA9514D,112 also supports SMBus protocols and clock stretching, making it suitable for mixed-protocol backplane environments.

How does the READY pin on the PCA9514D,112 indicate connection status?

The READY pin is an open-drain output that remains LOW during power-up initialization, ENABLE deassertion, or until bus idle/STOP detection completes. It transitions HIGH only after the internal connection circuitry successfully links SDAIN↔SDAOUT and SCLIN↔SCLOUT. A 10 kΩ pull-up resistor to VCC is required. This signal enables firmware to verify safe card attachment before initiating I²C transactions - a critical feature in the PCA9514D,112 for AdvancedTCA shelf management.

Can multiple PCA9514D,112 devices be cascaded in series?

Yes, but NXP recommends limiting cascaded PCA9514D,112 units to two in series due to cumulative dynamic offset voltage (≤150 mV per device). With four devices, total offset could reach ~0.5 V - approaching the 0.6–0.8 V rise-time accelerator threshold and risking false triggering. The PCA9514D,112's dynamic offset design allows safe parallel or series connection with other PCA951x devices (except PCA9515/16/17 B-side), but system-level validation is required beyond two stages.

What are the absolute maximum ratings for the PCA9514D,112 I/O pins?

The PCA9514D,112 I/O pins (SDAIN, SCLIN, SDAOUT, SCLOUT, READY, ENABLE) tolerate voltages from –0.5 V to +7 V relative to GND, independent of VCC. This 5.5 V tolerance ensures robustness against overshoot, undershoot, and mixed-voltage interfacing. Absolute maximum supply voltage is +7 V, and junction temperature must not exceed +125 °C. Exceeding these limits may cause permanent damage - the PCA9514D,112 is rated for continuous operation from –40 °C to +85 °C.