The block diagram shown here is a generic handset application where I²C I/O Expanders are the most common I²C devices utilized. As handsets become more complex in terms of the features offered, the number of General Purpose I/Os, or GPIOs, in the processor becomes more limited which creates the need for these I²C I/O Expanders. In this instance, I²C I/O Expanders can be used to add features such as camera control and LED lighting to the handset. They can also be used for maintenance duties, freeing up the limited GPIOs of the processor for other functions in the handset application.