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PCA9555APW,118

PCA9555APW,118

NXP Semiconductors
Interface - I/O Expanders 16b I2C BUS INTERUPT
3,988 in stock
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Overview

The PCA9555APW,118 is a 16-bit I2C-bus and SMBus parallel I/O expander designed for 1.65V to 5.5V VDD operation. It provides a simple solution when additional I/O is needed for ACPI power switches, sensors, push-buttons, or LEDs while minimizing the number of traces on the PCB.

Why Choose This Part

The device features a wide operating voltage range down to 1.65V and provides 5V tolerant I/Os, making it ideal for mixed-voltage systems. Its internal power-on reset and weak pull-up resistors on all I/Os ensure a stable, glitch-free state during system startup.

Applications

User Interface Controls
Reading multiple tactile switches or push-buttons and controlling status LEDs using only two I2C lines.
System Management
Monitoring board-level signals such as power-good indicators or hardware jumpers in server and networking equipment.
Sensor Aggregation
Collecting binary status signals from various sensors and triggering a host interrupt via the open-drain INT output.

Getting Started

To implement this device, connect the SDA and SCL lines to your host microcontroller's I2C bus with appropriate pull-up resistors. Use the hardware address pins (A0, A1, A2) to configure the unique bus address, and monitor the active-low INT pin to detect input state changes without constant polling.

Also Consider

MCP23017 MCHPMicrochip Technology - A widely used 16-bit I2C expander featuring high-speed 1.7MHz bus support and configurable interrupt behavior.
TCA9555 TITexas Instruments - A pin-to-pin compatible alternative with a similar voltage range and feature set for multi-source requirements.

Categories

Interface ICs > I/O Expanders
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