Diodes Incorporated PI4IOE5V9554LE

Overview

PI4IOE5V9554LE from Diodes Incorporated is an 8-bit I²C/SMBus GPIO expander with interrupt and reset functionality, designed for system-level I/O expansion in space-constrained embedded applications. It operates from 2.3V to 5.5V, supports 5V-tolerant I/Os, delivers ≤60μA active supply current at 5.5V/400kHz, and features open-drain active-low INT output for real-time input change detection in ACPI power switches and sensor interfaces.

For engineers reviewing the PI4IOE5V9554LE datasheet, PI4IOE5V9554LE pinout, PI4IOE5V9554LE application, or PI4IOE5V9554LE equivalent, key selection criteria include I²C address configurability (A0–A2), polarity inversion register support, noise-filtered SCL/SDA inputs, power-on reset behavior, and TSSOP-16 package compatibility with industrial temperature range (−40°C to +85°C).

Technical Context

The device implements a register-mapped I²C slave interface with four dedicated 8-bit registers: Input Port (read-only), Output Port (read/write), Polarity Inversion (read/write), and Configuration (read/write). All registers are accessible via standard I²C write/read transactions without auto-increment, requiring explicit command-byte retransmission per access.

Its I/O architecture uses weak internal pullups (~100kΩ) on input-configured pins and CMOS push-pull outputs when configured as drivers. The open-drain INT output asserts low when any input pin state changes and clears only upon reading the Input Port register or return to prior state - enabling efficient polling-free event handling in microcontroller systems.

Key Specifications

Pinout & Package

PI4IOE5V9554LE is packaged in a 16-pin TSSOP (173 mil wide), with 0.65mm pitch and exposed pad not connected internally. Pin layout supports standard PCB assembly and thermal relief design.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PCA9554APW and TCA6408AIPWR, PI4IOE5V9554LE uniquely combines 5V-tolerant I/Os, integrated SCL/SDA noise filtering, and per-bit polarity inversion - making it optimal for ruggedized industrial I/O expansion where signal integrity and mixed-voltage interoperability are critical.

Availability

PI4IOE5V9554LE is available at Aetrix Electronics and suitable for industrial HMI panels, ACPI-compliant power management subsystems, and sensor aggregation nodes requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for PI4IOE5V9554LE 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 manufacturer of discrete semiconductors and integrated circuits, specializing in high-performance, high-reliability components for industrial, computing, and consumer markets.

The PI4IOE5V9554LE belongs to Diodes' Pericom® I/O expansion portfolio, engineered specifically for low-power, noise-immune I²C peripheral interfacing in space- and power-constrained embedded systems.

FAQ

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

At power-on reset, all eight I/O pins (IO0–IO7) default to high-impedance inputs with internal ~100kΩ pullups to VCC. The Input Port, Output Port, Polarity Inversion, and Configuration registers initialize to their documented default values (e.g., Configuration Register = 0xFF), ensuring deterministic startup behavior without host initialization.

Can PI4IOE5V9554LE drive LEDs directly?

Yes - each I/O pin can source up to 10mA (at VCC=3.0V, VOH≥2.5V) or sink up to 13mA (at VCC=3.0V, VOL≤0.7V), sufficient for driving standard 2mA–5mA indicator LEDs. When used as an output, configure the corresponding bit in the Configuration Register to '0' and write desired logic level to the Output Port Register.

How does the interrupt output behave during I/O reconfiguration?

Changing an I/O pin from output to input may trigger a false interrupt if the external voltage on that pin differs from the stored value in the Input Port Register. To avoid spurious interrupts, read the Input Port Register immediately before reconfiguring direction, or ensure external pin state matches expected logic level prior to switching.

Is there a difference between PI4IOE5V9554LE and PI4IOE5V9554ALEX?

Yes - PI4IOE5V9554LE uses the base PI4IOE5V9554 device with I²C address range 0x20–0x27 (A2–A0), while PI4IOE5V9554ALEX uses the PI4IOE5V9554A variant with address range 0x38–0x3F. Both share identical electrical specs and pinout, enabling up to 16 total expanders (8 of each type) on one I²C bus.