Design of a Low Conversion Loss Mixer Integrated Driving Amplifier

A low conversion loss mixer integrated driving amplifier is designed and fabricatedby using O.5pm GaAs process. The circuit mainly consists of three sections: mixing section, balun and driving amplifier. The RF/LO frequency range of the designed mixer is 4 to 7GHz and the IF bandwidth is DC-2.5GHz. The chip achieves a conversion loss of less than 8.2dB. LO to RF isolation is greater than 34dB and LO to IF isolation is greater than 27dB. Input 1dB compression point is higher than 10.5dBm and input third-order intercept point is higher than 20dBm. The mixer employs a ring-diode and a spiral balun structure, which maintains a small chip area while achieving ultra-low frequency conversion loss. The overall size of the chip is 1.1 mmx l.2mm.