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This paper discusses the design and fabrication of a high-frequency wide-range frequency synthesizer based on a phase locked loop (PLL), varactorless LC-type voltage-controlled oscillator, and push-push frequency doubler. In addition, a high-speed programmable divider using multiphase selection is employed for channel switching. The proposed circuits were fabricated in a standard 90-nm CMOS process with a chip area of 0.8mm?1.1mm. The PLL dissipated 60mW when the supply was 1.2V. The measured phase noise of the frequency synthesizer at a frequency of 17.64GHz and offset of 1MHz was -97dBc/Hz. The work comprises a varactorless VCO, frequency doubler, and programmable divider.Channel switching uses a multiphase selection, high-speed programmable divider.The VCO uses a tunable transformer-base inductor and novel varactorless technique.

Pr-doped ZnO thin films (Zn1−xPrxO) (x = 0.00, 0.01, 0.02, 0.04) were prepared on fluorine-doped tin oxide substrates by means of the sol–gel method and spin coating technology, followed by rapid thermal annealing treatment at 800 °C. The influence of Pr content on the structural and optical properties of the Zn1−xPrxO thin film was examined and discussed. The wurtzite hexagonal structural characteristics were investigated by X-ray diffraction analysis, and Pr3+ substitution for Zn2+ ions was indicated. Finally, the typical bipolar current-voltage switching curves and electrical conduction model of Zn1−xPrxO film resistive random access memory devices were discussed and investigated for low resistance state/high resistance state in the initial forming process.