NXP Semiconductors PCA9507D,112

Overview

The PCA9507D,112 from NXP Semiconductors is a dual-supply 2-wire serial bus extender enabling bidirectional 3.3 V ↔ 5 V level translation with rise time acceleration on port A, supporting HDMI DDC, I²C-bus, and SMBus applications up to 18 m cable length and 1400 pF load capacitance. It isolates bus segments, prevents lock-up during arbitration, and operates across Standard- and Fast-mode (≤400 kHz) while maintaining full protocol compatibility.

For engineers reviewing the PCA9507D,112 datasheet, PCA9507D,112 pinout, PCA9507D,112 application, or PCA9507D,112 equivalent, key selection criteria include port-specific voltage translation behavior (static offset on port B vs. dynamic rise-time acceleration on port A), enable-controlled isolation timing, propagation delay asymmetry (91–350 ns), and SO8 package compatibility with HDMI DDC sink/source topologies.

Technical Context

The PCA9507D,112 implements asymmetric buffering: port A integrates a current-boosted rise time accelerator activated above 0.3V_CC(A), enabling fast edge rates for long-cable DDC lines; port B uses static-level-offset drivers with ~0.5 V LOW output and 70 mV input threshold hysteresis to prevent lock-up. Dual independent supplies (V_CC(A)/V_CC(B): 2.7–5.5 V) allow independent voltage domain translation without performance degradation.

Direction control is fully automatic and contention-free: falling edges below 0.3V_CC(A) trigger port B pull-down; falling edges below 0.4 V on port B trigger port A pull-down to near 0 V. The EN pin (active HIGH, internal 100 kΩ pull-up to V_CC(B)) enables system-controlled buffer activation only during bus-idle states to avoid protocol corruption.

Key Specifications

Pinout & Package

PCA9507D,112 is supplied in an SO8 package (SOT96-1), 3.9 mm body width, 8-lead plastic small outline format. Pin 1 is marked with a dot or bevel; pin numbering follows standard SO8 convention (counterclockwise from pin 1).

Key Features

Applications

Equivalent & Alternatives

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

Compared with PCA9517DP,118 and PCA9515D,118, the PCA9507D,112 uniquely delivers asymmetric port behavior (accelerated rise time + static offset), dual independent supplies, and HDMI DDC v1.3-compliant 18 m extension - making it the only option for long-cable, mixed-voltage, hot-plug-safe DDC implementations.

Availability

PCA9507D,112 is available at Aetrix Electronics and suitable for HDMI DDC interface design, industrial I²C bus extension, and multi-voltage SMBus segmentation requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for PCA9507D,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 company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and consumer electronics markets.

The PCA9507D,112 belongs to NXP's I²C-bus extender product line, engineered specifically for HDMI DDC compliance and long-cable, mixed-voltage I²C system isolation - addressing signal integrity challenges in display interface and industrial control applications.

FAQ

What is the maximum cable length supported by the PCA9507D,112 in HDMI DDC applications?

The PCA9507D,112 supports up to 18 meters of cable length on port A when driving a 1400 pF load, exceeding the HDMI DDC version 1.3 distance specification. This capability relies on the integrated rise time accelerator on port A (SDAA/SCLA), which actively boosts pull-up current during rising edges to maintain I²C-bus 1 µs rise time compliance under heavy capacitive loading. Performance is validated using 450 Ω pull-up resistors and 57 pF test loads per NXP's datasheet conditions.

Can the PCA9507D,112 be used with different supply voltages on port A and port B?

Yes, the PCA9507D,112 supports independent supply rails: V_CC(A) and V_CC(B) each operate from 2.7 V to 5.5 V, enabling true 3.3 V ↔ 5 V bidirectional level translation. For example, port A can be powered at 5 V (HDMI DDC line) while port B runs at 3.3 V (SoC I²C interface). Both supplies must exceed 2.7 V for driver activation, and power-up sequencing is unrestricted - either rail may rise first without functional impact.

How does the PCA9507D,112 prevent bus lock-up during I²C arbitration?

The PCA9507D,112 prevents lock-up through asymmetric port thresholds and hysteresis: port B has a 70 mV gap between its 0.43 V input threshold and 0.5 V output LOW level, ensuring a driven LOW on port B is not misinterpreted as a LOW by its own input. Direction control is automatic - falling edges below 0.3V_CC(A) trigger port B pull-down; falling edges below 0.4 V on port B trigger port A pull-down to near 0 V. This eliminates contention-induced deadlocks common in simpler repeaters.

Is the EN pin of the PCA9507D,112 required for basic operation?

No, the EN pin of the PCA9507D,112 is optional but recommended for system control. Internal power-on reset circuitry automatically enables drivers once V_CC(A) and V_CC(B) exceed 2.7 V. However, EN provides active HIGH control (with internal 100 kΩ pull-up to V_CC(B)) to isolate buses during power-up, reset, or fault recovery. It must only transition during global bus idle states - changing EN mid-transaction will hang the I²C bus.

What are the key differences between port A and port B of the PCA9507D,112?

Port A (SDAA/SCLA) features rise time acceleration, strong pull-down (≤0.2 V at 6 mA), and 0.3V_CC(A) input threshold triggering; it drives long cables or heavy loads. Port B (SDAB/SCLB) uses static level offset drivers with ~0.5 V LOW output and 0.43 V input threshold - designed to interoperate safely with other buffers like PCA9515 without offset accumulation. Port A can be star-connected; port B must avoid connection to other rise-time-accelerated devices per NXP's compatibility guidance.