The Analog Devices’ HMC554 is a passive, double-balanced mixer that can be used as an upconverter or downconverter between 11 and 20 GHz. The miniature, monolithic mixer is fabricated in a GaAs MESFET process and requires no external components or matching circuitry. The HMC554 provides excellent LO-to-RF and LO-to-IF isolation due to optimized balun structures. Measurements were made with the chip mounted into in a 50 ohm test fixture and include the parasitic effects of wire bond assembly. Connections were made with a 1 mil wire bond with minimal length (<12 mil).