PI4IOE5V6534Q 34-bit I/O Expander Diodes Incorporated PI4IOE5V6534Q 34-bit I/O Expander provides remote I/O expansion for most microcontroller families via the FC-bus interface. The PI4IOE5V6534Q is a simple solution when additional I/Os are needed while keeping interconnections to a minimum. The expander IC operates from 1.65V to 5.5V on the GPIO-port side and 0.8V to 3.6V on the SDA/SCL side. This allows the PI4IOE5V6534Q to interface with next-generation microprocessors and microcontrollers on the SDA/SCL side, where supply levels are dropping down to conserve power.