A liquid crystal display includes; a liquid crystal panel, and a DC-DC converter which receives an input voltage to generate an analog drive voltage and a gate-on voltage used to operate the liquid crystal panel, wherein the DC-DC converter includes a pulse width modulation circuit which modulates a pulse width of the analog drive voltage and the gate-on voltage, a boost converter which boosts the input voltage to output the analog drive voltage, and a charge pump which boosts one of the input voltage and the analog drive voltage to output the gate-on voltage, wherein when a high voltage stress test is performed, the DC-DC converter outputs the analog drive voltage boosted to a voltage level higher than a voltage level of the analog drive voltage during a normal operation, and outputs the gate-on voltage having a voltage level substantially equal to a voltage level of the gate-on voltage during the normal operation.