Provided is a delay adjustment device for adjusting delay of a strobe signal, which specifies when to read a data signal on a data line, with respect to the data signal in order to perform data transfer with an external memory. A testing unit 150 included in a delay adjustment unit is provided with a memory bandwidth monitoring unit 212 that monitors memory bandwidth in use on the data line used for data transfer with a memory circuit. The testing unit 150 performs delay adjustment when the memory bandwidth in use is lower than a predetermined threshold. Delay adjustment is performed by delaying the strobe signal from the data signal by a variety of predetermined delays and determining whether data transfer is successful at each delay, calculating an optimal delay, and thereafter delaying the strobe signal by the calculated delay.