A method of driving a lamp includes receiving a source power output from a power source; generating a first control signal; adjusting at least one attribute of the received source power based on the first control signal to generate a first lamp-driving power, the first lamp-driving power inducing a first tube current having a first tube current value within the lamp; after generating the first control signal, generating a second control signal, different from the first control signal; and adjusting at least one attribute of the received source power based on the second control signal to generate a second lamp-driving power, the second lamp-driving power inducing a second tube current having a second tube current value within the lamp, wherein the second tube current value is different from the first tube current value.