Patent ID: 7671661

Claim:
An integrated circuit (IC) comprising a plurality of circuit elements, comprising: a test circuit unit comprising a plurality of test circuit elements having element values and variations identical to a tuning-targeted circuit element of the plurality of circuit elements and at least one reference circuit element having a smaller variation than the tuning-targeted circuit element; a comparator configured to obtain a difference between values of a first signal and a second signal detected from the test circuit unit to measure the variation of the tuning-targeted circuit element; and a tuning unit configured to tune the variation of only the tuning-targeted circuit element according to the difference between a value of the first signal and a value of the second signal, wherein the test circuit unit further comprises: a first voltage divider comprising first and second test circuit elements, of the plurality of test circuit elements, connected to each other in series; and a second voltage divider comprising a third test circuit element, of the plurality of test circuit elements, and the at least one reference circuit element, wherein the third test circuit element is connected to the at least one reference circuit element in series, and wherein voltages having an identical value are applied to the first and second voltage dividers.