NXP Semiconductors PCA9511DP,118

Overview

PCA9511DP,118 from NXP Semiconductors (formerly Philips) is a hot-swappable I²C and SMBus bus buffer IC designed for live insertion of I/O cards into multi-point backplanes. It provides bidirectional SDA/SCL buffering with 1 V precharge, rise time accelerator circuitry (2 mA), and open-drain READY output. It operates from 2.7 V to 5.5 V and supports up to 400 kHz clock frequency in CompactPCI, VME, and AdvancedTCA systems.

For engineers reviewing the PCA9511DP,118 datasheet, PCA9511DP,118 pinout, PCA9511DP,118 application, or PCA9511DP,118 equivalent, this page delivers verified electrical parameters, TSSOP8 package details, ENABLE/READY interface behavior, rise time acceleration thresholds (0.6 V), and real-world hot-swap timing constraints including tIDLE (50–250 µs) and tEN (130 µs).

Technical Context

The PCA9511DP,118 implements a controlled connection architecture that isolates backplane and card capacitances until bus idle or STOP condition detection. Its internal 130 µs initialization delay and 50–250 µs bus-idle detection window prevent contention during hot insertion.

Rise time acceleration activates at 0.6 V on SDA/SCL lines using a 2 mA current source, enabling compliant rise times with weaker pull-ups. The device maintains high-impedance SDA/SCL pins when VCC = 0 V and supports clock stretching and multi-master arbitration without protocol modification.

Key Specifications

Pinout & Package

PCA9511DP,118 is housed in an 8-pin plastic TSSOP (Thin Shrink Small Outline Package) with 3 mm body width (SOT505-1), optimized for high-density backplane edge-mount applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I²C hot-swap buffer applications.

Compared with PCA9511D,118, the PCA9511DP,118 saves 35% board area in dense backplane edge layouts; versus TCA9511PWR, it offers tighter rise time accelerator threshold tolerance (0.6 V ±5% vs. ±10%) critical for noisy industrial SMBus environments.

Availability

PCA9511DP,118 is available at Aetrix Electronics and suitable for CompactPCI, VME, and AdvancedTCA systems requiring stable component supply, hot-swap reliability, and I²C/SMBus timing compliance across extended temperature ranges.

Supply support for PCA9511DP,118 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, formerly Philips Semiconductors, is a global leader in high-reliability interface and connectivity ICs, with deep expertise in I²C protocol IP and industrial bus architecture.

The PCA9511DP,118 belongs to NXP's hot-swap bus buffer product line, engineered specifically for carrier-grade telecom and industrial computing systems demanding zero-interruption field maintenance and deterministic bus isolation.

FAQ

What is the function of the READY pin on the PCA9511DP,118?

The READY pin on the PCA9511DP,118 is an open-drain output that signals successful backplane-to-card connection. It remains LOW during power-up, ENABLE assertion, or bus activity, and transitions HIGH only after the internal STOP/idle detection completes and SDAIN/SDAOUT plus SCLIN/SCLOUT are electrically coupled. For the PCA9511DP,118, READY sinks up to 3 mA at 0.4 V and requires an external 10 kΩ pull-up to VCC.

Does the PCA9511DP,118 support clock stretching and multi-master arbitration?

Yes, the PCA9511DP,118 fully supports clock stretching and multi-master arbitration because its bidirectional buffering preserves all I²C protocol signaling-including SCL hold-down and SDA collision detection-without introducing latency or altering timing margins. The PCA9511DP,118 does not insert delays into the data path during active communication, ensuring transparent operation for masters and slaves alike.

What is the purpose of the 1 V precharge feature in the PCA9511DP,118?

The 1 V precharge feature in the PCA9511DP,118 minimizes inrush current during hot insertion by biasing SDA and SCL pins to 1.0 V ±0.2 V before connection. This prevents large transient currents when a card with 0 V pins mates with a live backplane at 3.3 V or 5 V, reducing risk of bus corruption and electromagnetic interference. The PCA9511DP,118 implements this via internal 100 kΩ resistors to VCC during initialization.

How does the rise time accelerator in the PCA9511DP,118 improve system design?

The rise time accelerator in the PCA9511DP,118 injects a 2 mA current source on SDA/SCL lines once the input crosses 0.6 V, allowing compliant rise times with weaker pull-up resistors-reducing power consumption and easing routing in high-capacitance buses. For the PCA9511DP,118, this enables 400 kHz operation with 24 kΩ pull-ups at 5.5 V, versus ≤10 kΩ required without acceleration.

Can the PCA9511DP,118 operate with different supply voltages on backplane and card sides?

No-the PCA9511DP,118 has a single VCC pin and does not provide level translation between disparate voltage domains. Both backplane and card I²C buses must operate within the same 2.7 V to 5.5 V supply range. For mixed-voltage systems (e.g., 5 V backplane + 3.3 V card), external level shifters or devices like the PCA9517 are required; the PCA9511DP,118 itself only isolates capacitance, not voltage.