CAT9555数据手册集成电路（IC）的I/O扩展器规格书PDF

描述 Description

The CAT9555 is a CMOS device that provides 16-bit parallel input/output port expansion for I²C and SMBus compatible applications. These I/O expanders provide a simple solution in applications where additional I/Os are needed: sensors, power switches, LEDs, pushbuttons, and fans.The CAT9555 consists of two 8-bit Configuration ports (input or output), Input, Output and Polarity inversion registers, and an I²C/SMBus-compatible serial interface.Any of the sixteen I/Os can be configured as an input or output by writing to the configuration register. The system master can invert the CAT9555 input data by writing to the active-high polarity inversion register.The CAT9555 features an active low interrupt output which indicates to the system master that an input state has changed.The three address input pins provide the device's extended addressing capability and allow up to eight devices to share the same bus. The fixed part of the I²C slave address is the same as the CAT9554, allowing up to eight of these devices in any combination to be connected on the same bus.

特性 Features

• 400 kHz I2C bus compatible
• 2.3 V to 5.5 V operation
• Low standby current
• 5.0 V tolerant I/Os
• 16 I/O pins that default to inputs at power-up
• High drive capability
• Individual I/O configuration
• Polarity inversion register
• Active low interrupt output
• Internal power-on reset
• No glitch on power-up
• Noise filter on SDA/SCL inputs
• Cascadable up to 8 devices
• Industrial temperature range

应用 Application

• Input/output Port Expansion for Extended Addressing Capability
• White goods (dishwashers, washing machines)
• Handheld devices (cell phones, PDAs, digital cameras)
• Data Communications (routers, hubs and servers)

简介

CAT9555属于集成电路（IC）的I/O扩展器。由制造生产的CAT9555I/O 扩展器该系列器件可与微控制器、微处理器或类似器件结合使用，目的是增加可用于连接外设的信号连接数量。典型的工作概念涉及使用串行通信，只需主机设备上的几根 I/O 线，即可读/写扩展器设备上的许多输入/输出引脚的状态。该技术的通信速度不佳，但连通性较高，最适合快速响应不是很关键的应用，例如许多人机界面应用。