PI4IOE5V9555LEX

The PI4IOE5V9555 is an I2C-bus I/O expander that provides 16 bits of General Purpose parallel Input/Output (GPIO) expansion for I2C-bus/SMBus applications. It includes the features such as higher driving capability, 5V tolerance, lower power supply, individual I/O configuration, and smaller packaging. It provides a simple solution when additional I/O is needed for ACPI power switches, sensors, push buttons, LEDs, fans, etc.The PI4IOE5V9555 consists of two 8-bit configuration registers to configure the I/Os as either inputs or outputs, and two 8-bit polarity registers to change the polarity of the inputted data. The data for each input or output is kept in the corresponding Input or Output register. All registers can be read by the system master.The PI4IOE5V9555 open-drain interrupt output is activated and indicate to the system when any input state has changed. The power-on reset sets the registers to their default values and initializes the device state machine.Three input pins (A0, A1, A2) can select I2C-bus address of PI4IOE5V9555 from the eight preset address. It allows up to eight PI4IOE5V9555 to share the same I2C-bus/SMBus and provide maximum 128 I/Os.