High Speed, Low-Power GaAs Programmable Counters for Synthesizer Applications

For use in high-speed frequency synthesizer applications, we have developed a number of low-power GaAs DCFL components, including a divide-by-two circuit (5.1 GHz, 1.9 mW), dual-modulus (+10/11) prescaler (2.35 GHz, 15 mW), 4-bit ripple counter (2.35 GHz, 4.6 mW), 4-bit programmable prescaler (1.7 GHz, 36 mW), and a 4-bit programmable counter with ECL-compatible I/0s (1.8 GHz, 70 mW, excluding output drivers). 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 at a package temperature of 125°C, the circuits show less than a 10% degradation in their maximum clock frequency. The results demonstrate state-of-the-art high-frequency performance at extremely low power dissipation.