Monolithic InP HBT W-band VCO-static divider

The work presented here describes one implementation of a monolithic voltage controlled oscillator (VCO) combined with a static divide-by-4 function. The oscillator uses a dual Colpitts design producing complementary outputs. For this circuit the VCO range of oscillation was centered at 80 GHz and covered the range of 76 to 84 GHz. The range of operation was limited by the VCO since the divider by itself was measured to work at 100 GHz. This circuit demonstrates the main component of a monolithic W-band phased locked loop. The circuits use indium phosphide (InP) double heterojunction bipolar transistors (DHBT). Ft and Fmax was measured to be greater than 300 GHz. The emitter width is 0.45 microns.