Studies on CMOS Down-Converter with Double-Balanced Mixer along with Balun at S-Band

A CMOS down-converter with the combination of Gilbert Cell mixer and modified low voltage design technique using LC-balun is demonstrated in this paper. This forms a down-converter duo of mixer and balun. The RF, LO, and IF port frequencies are 3 GHz, 2.4GHz, and 600MHz, respectively. The measurement results of the proposed mixer-balun duo exhibit 13dB of conversion gain, -7.9 dBm of Input 1-dB compression point (P1dB), 2.51 dBm of Input 3rd order intercept point (IIP3), 3.8 dBm of Output 3rd order intercept point (OIP3) -43dB RF-IF, -42dB LO_IF Isolation and 1.2V supply voltage. This mixer-balun duo was fabricated at 65nm. CMOS technology. It can provide a 4 dB conversion gain even without connecting the LC-balun and 1.2V supply voltage is utilized.