Renesas Technology Corp.

Victor Company Of Japan, Limited

Akira Okasaka

Satoshi Tanaka

Satoshi Arayashiki

Toshiya Uozumi

Yasuyuki Kimura

Hirotaka Oosawa

Noriyuki Kurakami

Hirokazu Miyagawa

Tomoyuki Nonaka

Kazuki Ito

Masahiro Sasaki

Hiroyuki Hori

Akifumi Tabata

The invention provides a communication semiconductor integrated circuit (RF IC) that, when a transmission oscillator is incorporated into a semiconductor chip, secures the oscillation operation over a wide frequency range, prevents a deterioration of a transmission spectrum, and thereby enhances the accuracy of an oscillation frequency. The integrated circuit corrects a dispersion of the KV characteristic of the transmission oscillator by calibrating a current Icp of the charge pump inside the phase control loop. More in concrete, the integrated circuit measures a KV value Kv of the transmission oscillator, and calibrates the current Icp of the charge pump so that Kv&#xb7;Icp falls into a predetermined value.

Communication semiconductor integrated circuit device for use in a mobile communication device for correcting variations in the oscillation frequency of a transmission oscillator by calibrating a current of the charge pump

Calibrated PLL for wide band communication semiconductor integrated polar loop transmitter

A video signal processing apparatus includes an equalizer for delaying an input color signal by an adjustable phase retardation. A low pass filter is operative for delaying the input color signal by an adjustable phase retardation. A phase detector is operative for detecting a difference between a phase of an output signal of the equalizer and a phase of an output signal of the low pass filter, and outputting a signal representative of the detected phase difference. The phase retardation provided by the equalizer and the phase retardation provided by the low pass filter are adjusted in response to the output signal of the phase detector to maintain the difference between the phase of the output signal of the equalizer and the phase of the output signal of the low pass filter at a predetermined value, for example, 90 degrees.

Video signal processing apparatus

Growing community of inventors

Takasaki, Japan

Akira Okasaka