A temperature sensor includes a proportional to absolute temperature (PTAT) current generator configured to generate a first current proportional to temperature, a first complementary to absolute temperature (CTAT) current generator configured to generate a second current inversely proportional to temperature, a second CTAT current generator configured to generate a third current inversely proportional to temperature, and a temperature sensing unit configured to convert the first current, the second current, and the third current into a signal related to the temperature.