Abstract

GaAs microwave integrated circuits are now being developed for operation at frequencies as high as 40 GHz, while GaAs digital IC’s have been demonstrated with ring-oscillator propagation delays of 5-10 ps, with gate delays of 50-100 ps for larger-scale circuits. Digital IC’s are currently tested only by indirect technique (multistage propagation delay or cycle times), while microwave circuits are tested only by external scattering parameter measurement; if the circuit does not perform to expectations, the cause is not easily identified. Electrooptic sampling, providing picosecond-resolution measurements of the voltages within the IC, permits more detailed circuit evaluation.

© 1987 Optical Society of America