A delay-locked-loop control circuit and a method of controlling a delay-locked-loop. When the delay-locked-loop is in an off-operation mode, such as a power-down mode, a self-refresh emulation mode, a self-refresh mode, and the like, the delay-locked-loop is updated with a predetermined period, thereby preventing a malfunction of the delay-locked-loop. The delay-locked-loop has an oscillating portion which generates an oscillation signal having a predetermined period when in an OFF state; a pulse generating portion which generates a pulse signal having a predetermined period using the oscillation signal; a dividing portion which divides the pulse signal to generate a delay-locked-loop update signal; and a combining portion which combines the delay-locked-loop update signal and a delay-locked-loop on signal that is enabled by an external command to generate a delay-locked-loop control signal for controlling the delay-locked-loop.