Novel 10 GHz T-FF and D-FF ICs using GaAs MESFET source-input circuits

An input circuit configuration for very high speed digital ICs which provides good line termination without using a 50-ohm resistor is described. This is realized by featuring a source-input circuit of a common-gate FET. A resistor and capacitor network, attached to an ordinary common-gate FET circuit, can make a remarkable improvement in input resistance constancy and higher frequency gain. The technique of the source-input circuit was applied to SCFL flip-flops. T-FF and D-FF ICs were fabricated with 0.5 mu m WNx-gate BP-LDD GaAs MESFET technology, and tested. They demonstrated excellent high-frequency operations above 10 GHz.<
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