NXP Semiconductors PCA9534D,118

Overview

PCA9534D,118 from NXP Semiconductors is an 8-bit I²C-bus/SMBus GPIO expander in SO16 package, providing configurable input/output ports with active LOW open-drain interrupt output, 2.3 V to 5.5 V supply operation, and 5 V tolerant I/Os - used for ACPI power switches, push buttons, LEDs, and sensor interface in embedded control systems.

For engineers reviewing the PCA9534D,118 datasheet, PCA9534D,118 pinout, PCA9534D,118 application, or PCA9534D,118 equivalent, key selection considerations include I²C address configurability (A0–A2), polarity inversion register, low standby current (≤1 µA), interrupt-driven input change detection, and compatibility with standard-mode (100 kHz) and fast-mode (400 kHz) I²C buses.

Technical Context

The PCA9534D,118 implements a register-mapped I²C slave interface with four dedicated 8-bit registers: Input Port (read-only), Output Port (writeable), Polarity Inversion (bitwise active-HIGH/LOW toggle), and Configuration (per-pin input/output direction control). All registers default on power-on reset, with I/Os initialized as high-impedance inputs.

Its interrupt output activates when any configured input pin state differs from its corresponding Input Port register value, and deactivates upon reading the Input Port register or return to prior state. Internal noise filtering on SCL/SDA lines supports robust bus operation in electrically noisy environments.

Key Specifications

Pinout & Package

PCA9534D,118 uses the SO16 plastic small outline package (SOT162-1), 16-pin, 7.5 mm body width, with gull-wing leads and standard JEDEC pin 1 index marking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PCA9554D,118 and TCA9534APWR, the PCA9534D,118 offers the lowest standby current and no internal pull-ups - making it optimal for power-constrained designs where external biasing is already present or preferred.

Availability

PCA9534D,118 is available at Aetrix Electronics and suitable for industrial control panels, smart home sensor hubs, and ACPI power management systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for PCA9534D,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 leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with deep expertise in interface and power management ICs.

The PCA9534D,118 belongs to NXP's I²C GPIO expander product line, designed specifically to extend microcontroller I/O capability in space- and power-constrained embedded systems while maintaining SMBus compliance and industrial reliability.

FAQ

What is the I²C address range supported by PCA9534D,118?

The PCA9534D,118 supports seven fixed I²C slave addresses from 0x20 to 0x27, determined by the logic states of hardware pins A0, A1, and A2. This allows up to eight PCA9534D,118 devices to coexist on the same I²C bus without address conflict, enabling scalable I/O expansion in multi-node systems.

Does PCA9534D,118 require external pull-up resistors on SDA and SCL lines?

Yes, PCA9534D,118 requires external pull-up resistors on both SDA and SCL lines, as its I²C interface uses open-drain outputs. Typical values range from 2.2 kΩ to 10 kΩ depending on bus capacitance and speed; the PCA9534D,118 datasheet specifies 4.7 kΩ as a common recommendation for 100 kHz operation.

How does the interrupt output (INT) of PCA9534D,118 behave during power-on reset?

During power-on reset, the INT pin of PCA9534D,118 remains deasserted (HIGH) until the internal state machine initializes and the Input Port register reflects actual pin states. No false interrupts occur at startup because the interrupt condition is evaluated only after register initialization completes - ensuring clean, glitch-free INT behavior for the PCA9534D,118.

Can PCA9534D,118 drive LEDs directly, and what current limits apply?

Yes, PCA9534D,118 can drive LEDs directly when configured as outputs, with per-pin sink current up to 10 mA (VDD = 2.3 V) and total device sink limit of 100 mA. However, each I/O must be externally current-limited (e.g., series resistor), and the PCA9534D,118 datasheet mandates that total sourced current not exceed 85 mA to avoid exceeding thermal limits.

Is PCA9534D,118 pin-compatible with PCF8574-series expanders?

The PCA9534D,118 is pin-to-pin and I²C address compatible with the PCF8574 series, but software changes are required due to architectural enhancements - including separate polarity inversion and configuration registers, and absence of internal pull-ups. The PCA9534D,118 datasheet explicitly notes this in Application Note AN469.