CIRCUIT FOR VARIABLE RAMP CURRENT AND VARIABLE RAMP COMPENSATION CIRCUIT COMPRISING THE SAME

摘要

PURPOSE: A variable lamp current generating circuit and a variable lamp compensation circuit using the same are provided to adaptively change a lamp compensation circuit according to an input/output size, thereby appropriately compensating a lamp according to a duty cycle of a switch. CONSTITUTION: A control current generating part(11) generates a first current and a second current. The first current is determined by control voltage and input voltage of a switching type DC/DC voltage converter. The second current is determined by the control voltage and output voltage of the switching type DC/DC voltage converter. A lamp current generating part(13) creates a lamp current. The lamp current is proportional to the difference of the first current and the second current. The lamp current is proportional to the control voltage.