Patent ID: 7376039

Claim:
A semiconductor device having a sleep mode function, the device comprising a data storage circuit for preserving data when the semiconductor device is in the sleep mode, the data storage circuit comprising: a sleep mode control unit for outputting a scan control signal and a scan clock signal in response to one of a test control signal and a sleep mode control signal received from the outside, storing a first output data signal in a memory when the first output data signal is received, and outputting a first test pattern data signal as a scan data signal when the first test pattern data signal is received; and a first scan chain unit in signal communication with the sleep mode control unit for at least one of outputting a first normal data signal stored inside of the scan chain unit as the first output data signal to the sleep mode control unit in response to the scan control signal and the scan clock signal, and receiving and outputting the scan data signal to a first combinational circuit unit.