A folded Gilbert cell mixer has been implemented in a 0.13 μm CMOS technology. RF- and IF- frequencies of the down conversion mixer were 5.5GHz and 500MHz, respectively. A power conversion gain of 4.6dB and a noise figure of 14.2dB have been demonstrated experimentally under very low power consumption, only 4.2mW for the mixer core. Considering the overall performances of the circuit, this paper shows that the folded mixer architecture is one of the most interesting frequency converter solutions for low-power mobile applications.