NXP Semiconductors PCA9536D,112

Overview

PCA9536D,112 from NXP Semiconductors is a 4-bit I²C-bus/SMBus GPIO expander in SO8 package, providing configurable parallel input/output expansion for embedded control applications. It operates from 2.3 V to 5.5 V, features 5 V-tolerant I/Os with 100 kΩ internal pull-ups, supports up to 400 kHz clock frequency, and includes polarity inversion and configuration registers - enabling use in ACPI power switches, LED drivers, and sensor interface subsystems.

For engineers reviewing the PCA9536D,112 datasheet, PCA9536D,112 pinout, PCA9536D,112 application, or PCA9536D,112 equivalent, key selection criteria include I²C address compatibility (fixed 0x41), low standby current (<1 µA at VDD=5.5 V, VI=VDD), noise-filtered SCL/SDA inputs, and SO8 thermal performance for industrial temperature range (−40 °C to +85 °C).

Technical Context

The PCA9536D,112 implements a register-mapped I²C slave interface with four dedicated 4-bit registers: Input Port (read-only), Output Port (writeable output state), Polarity Inversion (bitwise active-HIGH/LOW toggle), and Configuration (input/output direction per I/O). All registers are accessible via standard I²C write/read sequences using command bytes 0–3.

Its I/O architecture uses CMOS transmission gates with weak 100 kΩ pull-up resistors on reset; each pin defaults to high-impedance input. The device incorporates internal power-on reset (VPOR = 1.7–2.2 V), ESD protection exceeding 2000 V HBM, and no-glitch behavior during power-up - ensuring deterministic initialization without external reset circuitry.

Key Specifications

Pinout & Package

PCA9536D,112 is housed in an SO8 package (SOT96-1): plastic small outline, 8 leads, 3.9 mm body width, 1.27 mm lead pitch. Pin 1 index located at top-left corner with notch or dot marking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TCA6408A and PCA9534A, PCA9536D,112 offers minimal pin count and lowest quiescent current for space-constrained 4-bit expansion, but lacks interrupt capability and has fewer I/Os - making it optimal for simple, polling-based subsystems where board area and power are primary constraints.

Availability

PCA9536D,112 is available at Aetrix Electronics and suitable for industrial sensor interfaces, LED status panels, ACPI power management subsystems, and fan speed monitoring requiring stable component supply across extended temperature ranges.

Supply support for PCA9536D,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 specializing in secure connectivity solutions for automotive, industrial, and IoT applications, with over 50 years of analog and mixed-signal IP heritage.

The PCA9536D,112 belongs to NXP's I²C-bus GPIO expander product line, designed specifically to simplify digital I/O expansion in resource-constrained embedded systems while maintaining robustness in electrically noisy environments.

FAQ

What is the I²C slave address of the PCA9536D,112?

The PCA9536D,112 has a fixed 7-bit I²C slave address of 0x41 (binary 1000001), with the R/W bit appended during transmission. This address is non-configurable and allows only one PCA9536D,112 per I²C bus segment without address conflict.

Does the PCA9536D,112 require an external reset circuit?

No, the PCA9536D,112 includes an internal power-on reset (POR) circuit that initializes all registers to default values when VDD rises above VPOR (1.7–2.2 V). No external reset signal or RC network is needed for reliable startup behavior.

Can the PCA9536D,112 drive LEDs directly?

Yes - the PCA9536D,112 can sink up to 10 mA per I/O pin (at VOL = 0.7 V, VDD = 2.3 V) and source limited current via pull-ups. For typical 2–20 mA LEDs, configure the pin as output and connect the LED anode to VDD and cathode to the I/O pin for direct sinking operation.

What is the function of the Polarity Inversion register in the PCA9536D,112?

The Polarity Inversion register (Register 2) allows bitwise inversion of Input Port register values. When bit Nn = 1, the corresponding Input Port bit In is logically inverted on read - enabling native support for active-LOW sensors or switches without software XOR operations.

Is the PCA9536D,112 compatible with SMBus protocols?

Yes, the PCA9536D,112 is fully SMBus 2.0 compliant: it supports SMBus Alert response, timeout detection, and adheres to SMBus voltage thresholds (VIH ≥ 0.7×VDD, VIL ≤ 0.3×VDD) and timing specifications up to 100 kHz standard mode.