a lamp having an LED channel;

a channel current control unit configured to generate a channel reference voltage that has a slope and rises at the time of enabling the LED channel and falls at the time of disabling the LED channel, and has a flat voltage level in between the rise section and fall section; and

a channel driving circuit configured to control a channel current of the LED channel using a voltage corresponding to a current flowing through the LED channel and the channel reference voltage, wherein the channel current control unit comprises: a ramp voltage generator configured to generate a ramp voltage with a rising/falling slope at the point of time that the LED channel is enabled/disabled; and a selector configured to select any one of the ramp voltage and a reference voltage as the channel reference voltage according to a selection signal, and provide the selected voltage to the channel driving circuit and wherein the ramp voltage generator comprises: a ramp capacitor; a charging current unit configured to charge the ramp capacitor such that the ramp voltage rises with a slope at the point of time that the LED channel is enabled; and a discharging current unit configured to discharge the ramp capacitor such that the ramp voltage falls with a slope at the point of time that the LED channel is disabled.