US Patent 7038512 Closed-loop independent DLL-controlled rise/fall time control circuit

A system and method for processing signals determines rise and fall times of a driving signal, compares the rise and fall times to desired values, and independently controls the rise and fall times to equal the desired values. The rise and fall times may be controlled by generating one or more first correction bits based on a difference between the rise time and a corresponding one of the desired values, generating one or more second correction bits based on a difference between the fall time and a corresponding one of the desired values, and then separately applying the bits to independently control the rise and fall times of the driving signal. The driving signal may be an I/O signal or another type of signal.