Diodes Incorporated PI4IOE5V9536UEX

Overview

PI4IOE5V9536 from Diodes Incorporated is a 4-bit I²C/SMBus GPIO expander IC with 5V-tolerant I/Os, 2.3V–5.5V supply operation, and individual I/O direction/polarity configuration. It serves as a low-power parallel I/O extension for ACPI power switches, push buttons, LEDs, and fan control in embedded systems.

For engineers reviewing the PI4IOE5V9536 datasheet, PI4IOE5V9536 pinout, PI4IOE5V9536 application, or PI4IOE5V9536 equivalent, key selection criteria include I²C clock support up to 1 MHz, 100 kΩ internal pull-up on reset, noise-filtered SCL/SDA inputs, and MSOP-8 packaging for space-constrained designs.

Technical Context

The PI4IOE5V9536 implements a register-mapped I²C slave interface with four dedicated I/O pins (IO0–IO3), each configurable as input or output via the Configuration Register (Register 3). Polarity inversion is supported per-pin through Register 2, enabling flexible signal alignment without external logic.

It features a hardware power-on reset circuit that initializes all registers-including default 4-input state with 100 kΩ pull-ups-and enforces V_POR = 1.16–1.41 V. The I/O structure supports 5V-tolerant inputs even when V_CC = 2.3 V, and output drive capability reaches ±10 mA at V_CC = 3.0 V with V_OL ≤ 0.7 V.

Key Specifications

Pinout & Package

Package: MSOP-8 (U), 3.0 mm × 3.0 mm body, 0.65 mm pitch, RoHS-compliant, green, lead-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TCA6408A and PCA9536, the PI4IOE5V9536 uniquely combines 4-bit flexibility with built-in pull-ups, polarity inversion, and noise filtering-making it optimal for compact, robust, and software-efficient I/O expansion where signal integrity and startup determinism matter.

Availability

PI4IOE5V9536 is available at Aetrix Electronics and suitable for ACPI power management, LED status indication, fan tach feedback, and sensor interface aggregation requiring stable component supply across industrial, computing, and networking product lifecycles.

Supply support for PI4IOE5V9536 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

Diodes Incorporated is a global semiconductor company specializing in discrete, analog, and mixed-signal ICs for power management, signal integrity, and connectivity applications.

The PI4IOE5V9536 belongs to Diodes' I²C GPIO expander product line, designed specifically for space-constrained embedded systems needing reliable, low-power, and 5V-tolerant I/O extension without external support components.

FAQ

What is the default I/O configuration after power-on reset?

At power-on reset, all four I/O pins (IO0–IO3) default to high-impedance inputs with internal 100 kΩ pull-up resistors enabled. The Configuration Register (Register 3) is initialized to 0xFF, and the Input Port Register reflects externally applied logic levels. This ensures predictable, glitch-free startup without host initialization dependency.

Can the PI4IOE5V9536 drive 5 V logic inputs while operating from a 3.3 V supply?

Yes-the I/O pins are 5V-tolerant up to 6.0 V regardless of V_CC, so they can safely receive 5 V signals when V_CC = 3.3 V. However, output high-level voltage (V_OH) is limited to ~2.6 V at 3.0 V supply and –10 mA load, making it unsuitable for driving 5 V TTL inputs actively; use as input-only or with level-shifting for 5 V output compliance.

Does the device support I²C clock stretching or auto-increment addressing?

No-the PI4IOE5V9536 does not implement clock stretching or auto-increment addressing. Each register access requires explicit command byte transmission before read/write operations. This simplifies host firmware but requires full register addressing in every transaction, limiting burst efficiency compared to auto-increment devices like PCA9555.

How is ESD protection implemented, and what test standards apply?

The PI4IOE5V9536 provides 4 kV HBM (Human Body Model) and 1 kV CDM (Charged Device Model) ESD protection on all pins per JEDEC JS-001 and JESD22-C101 standards. This is achieved through integrated clamp diodes and optimized layout-no external TVS devices are needed for basic handling and board-level ESD immunity in Class 1B/2 environments.