NXP Semiconductors PCA9534BS,118

Overview

PCA9534BS,118 from NXP Semiconductors is an 8-bit I²C-bus/SMBus GPIO expander in HVQFN16 (4 × 4 × 0.85 mm) package, providing configurable input/output ports, polarity inversion, and open-drain interrupt output. It operates from 2.3 V to 5.5 V, tolerates 5 V on I/Os, supports up to 400 kHz clock frequency, and features low standby current (≤1 µA). It is used in embedded subsystems for ACPI power switches, push-button interfaces, LED control, and sensor monitoring.

For engineers reviewing the PCA9534BS,118 datasheet, PCA9534BS,118 pinout, PCA9534BS,118 application, or PCA9534BS,118 equivalent, key selection considerations include I²C address configurability (A0–A2), interrupt-driven input change detection, 5 V-tolerant I/Os with no internal pull-ups, and thermal-enhanced HVQFN packaging for space-constrained industrial and portable designs.

Technical Context

The PCA9534BS,118 implements a register-mapped I²C slave interface with four dedicated 8-bit registers: Input Port (read-only), Output Port (writeable), Polarity Inversion (bit-wise active-HIGH/LOW toggle), and Configuration (per-pin input/output direction control). All registers default on power-on reset, and the device uses internal power-on reset circuitry with VPOR = 1.7–2.2 V.

Its interrupt output (INT) is open-drain and asserts when any configured input pin state differs from its corresponding Input Port register value. The I/O structure supports 5 V tolerance via clamping diodes, and noise filtering on SCL/SDA inputs suppresses spikes ≤50 ns. No glitch occurs at power-up due to synchronized register initialization.

Key Specifications

Pinout & Package

HVQFN16 package (SOT629-1), 4 mm × 4 mm × 0.85 mm body, thermally enhanced with exposed center pad soldered to PCB ground plane for improved thermal dissipation and electrical stability.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar GPIO expander applications.

Compared with PCA9534PW,118, the PCA9534BS,118 offers superior thermal performance and 30% smaller footprint; compared with PCA9554BS,118, it delivers 100× lower standby current-making it optimal for energy-sensitive edge nodes where every microamp matters.

Availability

PCA9534BS,118 is available at Aetrix Electronics and suitable for industrial control panels, smart home sensor hubs, LED status indicator arrays, and embedded fan speed controllers requiring stable component supply and long-term production continuity.

Supply support for PCA9534BS,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 is a global semiconductor company specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The PCA9534 product line delivers low-power, I²C-based GPIO expansion for resource-constrained embedded systems-designed specifically to reduce MCU GPIO pressure while maintaining robust industrial-grade ESD, latch-up, and thermal reliability.

FAQ

What is the maximum I²C clock frequency supported by the PCA9534BS,118?

The PCA9534BS,118 supports Fast-mode I²C operation up to 400 kHz, as confirmed in the dynamic characteristics table (Table 11). This allows faster register access and reduced transaction latency versus Standard-mode (100 kHz), which is especially beneficial in time-critical industrial monitoring applications where the PCA9534BS,118 serves as a sensor interface hub.

Does the PCA9534BS,118 have internal pull-up resistors on its I/O pins?

No, the PCA9534BS,118 explicitly omits internal I/O pull-up resistors-unlike the PCA9554 variant-to minimize standby current. This design choice reduces leakage and enables sub-µA quiescent operation, making the PCA9534BS,118 ideal for battery-powered systems where external pull-ups can be added selectively only where needed.

How does the interrupt output (INT) of the PCA9534BS,118 behave during power-up?

The PCA9534BS,118 features a synchronized power-on reset that initializes all registers-including the Input Port and Configuration registers-to their default states before releasing the INT pin. As a result, INT remains deasserted (HIGH) at power-up unless an input pin transitions *after* reset completion, preventing spurious interrupts during system boot-critical for reliable operation in the PCA9534BS,118's role as a sensor interface in safety-critical subsystems.

Can the PCA9534BS,118 operate with a 3.3 V supply while interfacing with 5 V sensors?

Yes, the PCA9534BS,118 supports 5 V-tolerant I/Os up to 5.5 V regardless of VDD level. When powered from 3.3 V, its IO0–IO7 pins safely accept 5 V logic inputs from sensors or switches-eliminating the need for external level translators. This capability is explicitly specified in the static characteristics table (Table 10) and is a core design feature of the PCA9534BS,118 for mixed-voltage system integration.

What package type is used for the PCA9534BS,118, and why is the exposed pad important?

The PCA9534BS,118 uses the HVQFN16 package (SOT629-1), 4 mm × 4 mm × 0.85 mm, with an exposed center pad. That pad must be soldered to a PCB ground plane with thermal vias-not left floating-as it serves as both a thermal conduction path (reducing junction temperature rise) and a low-inductance ground reference for noise-sensitive I²C signaling. Omitting this step compromises both thermal reliability and signal integrity in the PCA9534BS,118's operation.