Diodes Incorporated PI4IOE5V9555LE

Overview

PI4IOE5V9555LE from Diodes Incorporated is a 16-bit I²C-bus/SMBus I/O expander with 5V-tolerant GPIOs, active-low open-drain interrupt output, and individual I/O direction/polarity configuration. It operates from 2.3V to 5.5V, supports up to 400 kHz clock frequency, and delivers 8 mA low-level drive per I/O at 2.3V. It is used in ACPI power switches, push-button interfaces, LED drivers, and sensor monitoring in space-constrained embedded systems.

For engineers reviewing the PI4IOE5V9555LE datasheet, PI4IOE5V9555LE pinout, PI4IOE5V9555LE application, or PI4IOE5V9555LE equivalent, key selection criteria include I²C address configurability (A0–A2), interrupt behavior tied to input-state changes, 5V tolerance on all I/Os, and dual-package availability (TSSOP-24 and TQFN-24) for layout flexibility.

Technical Context

The PI4IOE5V9555LE implements an I²C slave interface with eight configurable device addresses (0x20–0x27) via A0–A2 pins. Its register map includes two 8-bit configuration registers (Port 0/1), two polarity inversion registers, and mirrored input/output port registers - all accessible via standard I²C read/write sequences with auto-increment addressing across register pairs.

Interrupt generation is edge-triggered and asynchronous: INT asserts when any configured input pin transitions, and clears only upon reading the corresponding input port register. The internal power-on reset circuit activates at VPOR = 1.16–1.41 V and initializes all I/Os as high-impedance inputs with weak pull-ups to VCC.

Key Specifications

Pinout & Package

PI4IOE5V9555LE is available in TSSOP-24 (L) and TQFN-24 (ZD) packages. Both are 24-pin surface-mount packages with identical pin functions and electrical characteristics. Pin numbering differs between packages; refer to Figures 1 and 2 in DS41303 Rev 1-2 for top-view layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I²C GPIO expander applications.

Compared with PCA9555D and MCP23017, the PI4IOE5V9555LE uniquely combines 5V I/O tolerance, per-bit polarity inversion, and integrated SCL/SDA noise filtering - making it optimal for mixed-voltage industrial I/O expansion where signal integrity and layout simplicity are critical.

Availability

PI4IOE5V9555LE is available at Aetrix Electronics and suitable for industrial HMIs, embedded PC power management, smart sensor nodes, and LED status panel designs requiring stable component supply and long-term manufacturability.

Supply support for PI4IOE5V9555LE 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 analog ICs, specializing in high-reliability power management, signal integrity, and connectivity solutions for industrial, computing, and consumer markets.

The PI4IOE5V9555LE belongs to Diodes' Pericom® I/O expansion portfolio, designed specifically for space-constrained embedded systems needing robust, low-power, mixed-voltage GPIO extension over I²C.

FAQ

What is the maximum total current rating for all I/O pins combined?

The PI4IOE5V9555LE has a total sourced current limit of 160 mA and a total sunk current limit of 200 mA. Each octal group (IO0_0–IO0_7 or IO1_0–IO1_7) must not exceed 100 mA, and individual I/O pins are limited to ±25 mA. These limits are enforced by external current-limiting resistors per pin, as specified in the Absolute Maximum Ratings table.

How does the interrupt output behave when multiple input pins change state simultaneously?

The INT pin asserts low on the first detected input transition and remains asserted until the corresponding input port register (Port 0 or Port 1) is read. Simultaneous changes across both ports keep INT active until both input registers are read - each port's interrupt is cleared independently, supporting precise event attribution in multi-sensor systems.

Can the PI4IOE5V9555LE operate with a 1.8 V I²C master?

No. While the I/O pins tolerate up to 5.5 V, the SCL and SDA inputs require VIH ≥ 0.7×VCC (min 1.61 V at VCC = 2.3 V). A 1.8 V master may not reliably meet VIH thresholds when VCC < 2.57 V. For true 1.8 V compatibility, use a level-shifting buffer or select a dedicated 1.8 V–tolerant expander like the TCA6424A.

Is there a difference in electrical performance between the TSSOP-24 and TQFN-24 packages?

No. Both packages share identical DC and AC electrical specifications, thermal resistance values, and register behavior. The TQFN-24 offers lower thermal impedance (θJA ≈ 50°C/W vs. 70°C/W for TSSOP) and smaller PCB footprint, while the TSSOP-24 provides easier manual soldering and in-circuit probing access.