The HMC259 chip is a broadband sub-harmonically pumped (x2) balanced MMIC passive mixer which can be used as an upconverter or downconverter. The chip utilizes a GaAs MESFET process resulting in a small overall chip area of 1.9mm2. This chip has a very wide IF bandwidth of DC-13 GHz. The 2LO to RF isolation is excellent eliminating the need for additional filtering. All data is with the chip in a 50 ohm test fixture connected via 0.025mm (1 mil) diameter wire bonds of minimal length <0.31mm (<12 mils). This device is a much smaller and more reliable replacement to hybrid diode mixer designs.