Patent attributes
There is provided a bias current generating apparatus capable of providing a bias current where a characteristic change is compensated, to one of an analog circuit and RF circuit where various characteristic changes occur according to a temperature, by generating bias currents having a plurality of temperature coefficients. The apparatus includes: a positive temperature coefficient current generator generating a positive temperature coefficient current in direct proportion to an absolute temperature; a zero temperature coefficient current generator generating a zero temperature coefficient current constant regardless of the absolute temperature; and an adjustable temperature coefficient current generator generating and outputting an adjustable temperature coefficient current by amplifying the positive temperature coefficient current by A times, amplifying the zero temperature coefficient current by B times, adding the two amplified temperature coefficient currents, wherein a temperature coefficient of the adjustable temperature coefficient current is varied by adjusting sizes of the A and B.