PI4IOE5V6416Q Automotive I2C-Bus I/O Expander Diodes Incorporated PI4IOE5V6416Q Automotive I2C-Bus I/O Expander provides remote I/O expansion for most microcontroller families via the I2C-bus interface. This 16-bit expander offers a simple solution when additional I/Os are needed while keeping interconnections to a minimum, such as in battery-powered mobile applications for interfacing with sensors, buttons, keypads, and other Human Machine Interface (HMI) devices.