In this paper, we have investigated the noise characteristics of a low-voltage temperature sensor designed in standard CMOS technology. It looks like a traditional temperature sensitive Wheatstone bridge (fabricated using polysilicon resistors layers of positive and negative temperature coefficients), followed by a low-noise low-offset, low supply voltage differential amplifier, which improves the circuit sensitivity to about 20 mV/K. The temperature resolution is about 0.01 o . Noise considerations on suitable different OTA amplifiers are also presented and compared with other CMOS and bipolar temperature sensors.