A 10-GHz frequency divider using selectively doped heterostructure transistors

We report the first complementary clocked frequency divider using dual gate selectively doped heterostructure transistors (SDHT's). The circuit employs a master-slave flip-flop design which consists of four direct coupled AND-NOR gates. The nominal gate length and the gate-gate, separation in the dual gate SDHT's are 1 µm. A maximum dividing frequency of 10.1 GHz at 77 K was achieved; at this frequency the circuit dissipated 49.9 mW at 1.67-V bias. This is the highest operating frequency reported for static frequency dividers at any temperature. At room temperature the dividers were operated successfully at frequencies up to 5.5 GHz with a total power dissipation of 34.8 mW at 1.97-V bias. The lowest speed-power product at room temperature was obtained at 5 GHz with 14.9-mW power dissipation at 1.45-V bias.