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Tatsuo OTSUKI Tsuyoshi TANAKA Noriyuki YOSHIKAWA Akio SHIMANO Hiromitsu TAKAGI Gota KANO
A GaAs monolithic high-frequency modulator IC which provides an efficient suppression of the RIN of a laser diode under application of the high-frequency power to the diode is reported. The oscillation frequency and the output power of the IC are designed to be 800 MHz and 15 dBm, respectively. Use of the IC permitted suppression of the RIN of the laser diode by almost 10 dB/Hz.
Masahiro NISHIUMA Shutaro NAMBU Masahiro HAGIO Gota KANO
A new GaAs monolithic negative feedback amplifier using a dual-gate MESFET for A.G.C. function has been developed. Such a low NF value as 1.8 to 2.5 dB with a gain of 10 to 12 dB over a frequency range of 50 to 2,000 MHz has been obtained. The gain reduction of about 30 dB was achieved over the same frequency range by means of the second-gate bias. A comparison of the performance between negative feedback amplifiers using a dual-gate FET and a single-gate FET is also discussed.
Koji ARITA Eiji FUJII Yasuhiro SHIMADA Yasuhiro UEMOTO Masamichi AZUMA Shinichiro HAYASHI Toru NASU Atsuo INOUE Akihiro MATSUDA Yoshihisa NAGANO Shin-ich KATSU Tatsuo OTSUKI Gota KANO Larry D. McMILLAN Carlos A. Paz de ARAUJO
Characterization of silicon devices incorporating the capacitor which uses ferroelectric thin films as capacitor dielectrics is presented. As cases in point, a DRAM cell capacitor and an analog/digital silicon IC using the thin film of barium strontium titanate (Ba1-xSRxTiO3) are examined. Production and characterization of the ferroelectric thin films are also described, focusing on a Metal Organic Deposition technique and liquid source CVD.
Masanori HIROSE Masahiro KUME Akio YOSHIKAWA Takao SHIBUTANI Takashi SUGINO Kunio ITOH Gota KANO Iwao TERAMOTO
An array of monolithically integrated composite-cavity lasers which has been fabricated on the basis of the chemical etching technique is reported. Each composite-cavity laser consists of a laser and an external reflector, and the reflector is used also as a photodetector. The array is designed so that each laser can be operated independently of the other for parallel processing of optical data with high stability operation and independent monitoring capability. Experimental devices have been successfully fabricated.
Takayuki MORISHITA Youichi TAMURA Tatsuo OTSUKI Gota KANO
We have developed a 64-neuron electrically trainable BiCMOS analog neuroprocessor based on 3-layered PDP networks with a feedforward time as short as 10 µs which is equivalent to the operation speed as high as 108 multiplications per second. A crucial point in this development is application of a dynamic refreshment technique to a weighting circuit. A sufficiently long retention time of the synapse weight has thereby been attained, leading to a practical operation of the neuroprocessor.
Kunihiko KANAZAWA Masahiro HAGIO Masaru KAZUMURA Gota KANO
A 12-GHz-band GaAs monolithic dual-gate FET mixer using a novel circuit configuration has been demonstrated. Adoption of a negative feedback circuit has reduced the output impedance of the mixing dual-gate FET down to 330 Ω, which is approximately one fourth that of conventional dual-gate FET mixers, resulting in good matching to the next state. An experimental MMIC mixer, which included an IF buffer amplifier, exhibited a 3.4-4.2-dB conversion gain with a 11.3-11.6-dB SSB noise figure in the 11.7-12.2-GHz RF band.