8-bit Port exPander with interruPt outPut 2 adddress inPuts for uP to 4 devices on one bus 25mA sink/source caPability Per I/O ... 8-bit Port exPander with interruPt outPut 3 adddress inPuts for uP to 8 devices on one bus 25mA sink/source caPability Per I/O ... 8-Bit I/O ExPander with Serial Interface