Patent ID: 8245121

Claim:
A signal control circuit for outputting data of a plurality of bits, comprising: a data generation block to generate the data of the plurality of bits; a data storage block to store the data generated by the data generation block and output the data to an external circuit in response to a request for outputting the data; a data retention block to retain data output in a preceding session; a data judgment block to judge the number of changed bits when the data is output from the data generation block, by comparing each bit of the data output in the preceding session and a corresponding bit of the data to be sent in a current session, and output position information indicating the position of each changed bit and count information indicating the number of changed bits with respect to the data to be sent in the current session when the number of changed bits has reached a predetermined level; and an output control block to receive the position information and the count information, keep a time period for stabilizing the change in value of said each changed bit indicated by the position information when the data is output, and direct the data storage block to send the value of said each changed bit indicated by the position information to the external circuit after the kept period has passed.