GaAs prescalers and counters for fast-settling frequency synthesizers

A number of low-power GaAs direct-coupled FET logic (DCFL) components developed for use in compact, fast-settling phase-locked-loop-type frequency synthesizer applications are discussed. These components include a divide-by-two circuit (2.7 GHz, 1.3 mW), a dual-modulus (/10/11) prescaler (2.4 GHz, 15 mW), a 4-b ripple counter (2.4 GHz, 4.6 mW), a 4-b programmable prescaler (1.7 GHz, 36 mW), a 3-b programmable counter (1.9 GHz, 57 mW), a 4-b programmable counter (1.8 GHz, 70 mW), and a 6-b programmable counter (1.4 GHz, 90 mW). The circuits are fabricated with a high-yield refractory self-aligned gate process and operate over a wide variation in power supply voltage and temperature. When operated over a -55 to 125 degrees C temperature range, the circuits show less than 20% degradation in their maximum clock frequency. The results demonstrate state-of-the-art high-frequency performance at extremely low power dissipation.<
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