SEMICONDUCTOR UNIT OF SiP TYPE

PROBLEM TO BE SOLVED: To provide a semiconductor unit capable of reducing the number of pins in a package, capable of compatifying a size, and capable of enhancing concurrently controllability and observability, in the semiconductor device of an SiP type. SOLUTION: The first semiconductor device is operated in response to a signal input from an outside of the semiconductor unit via an outer pin of the package, the second semiconductor device is operated in response to a signal input from the first semiconductor device into the second semiconductor device, and a signal output from the second semiconductor device is input into the first semiconductor device. The first semiconductor device is provided with the first switching circuit for switching the signal input from the outside of the semiconductor unit so as to be input into the second semiconductor device, in a test mode, and the second switching circuit for switching the signal input from from the second semiconductor device into the first semiconductor device so as to be output to the outside of the semiconductor unit in the test mode. COPYRIGHT: (C)2007,JPO&INPIT