39.5-GHz static frequency divider implemented in AlInAs/GaInAs HBT technology

A static divide-by-four frequency divider operating at 39.5-GHz input frequency is reported. Graded emitter-base junction AlInAs/GaInAs heterojunction bipolar transistor (HBT) technology lattice-matched to InP substrates has been used to implement the divider. The graded junction HBTs feature unity gain cutoff frequency and maximum frequency of oscillation of 130 GHz and 91 GHz, respectively. The devices have a very low turn-on voltage of about 0.7 V at collector current density of 5*10/sup 4/ A/cm/sup 2/. The divider operated at a power supply voltage of -3 V and consumes a total DC power of 425 mW, corresponding to 77 mW per flip-flop.<
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