Kabushiki Kaisha Toshiba

Hideki Oto

Tadashi Imai

Shuji Abe

Katsuya Kudo

Toshimasa Adachi

A tuner circuit comprising a first frequency conversion means 14 for converting a high frequency input signal into a first intermediate frequency signal according to a first local oscillation signal, a second frequency conversion means 19 for converting the first intermediate frequency signal from the first frequency conversion means 14 into a second intermediate frequency signal according to a second local oscillation signal, a first PLL means 24 for controlling the first local oscillation signal so as to synchronize the phase of the signal with that of a reference oscillation signal having a fixed frequency, a second PLL means 31 for controlling the second local oscillation signal so as to synchronize the phase of the signal with that of a reference oscillation signal. In the first PLL means 24, a phase comparison frequency is set to a frequency higher than a specified value. In the second PLL means 31, a phase comparison frequency is set to a frequency lower than a specified value.

Tuner circuit

A digital data receiver having a converter for frequency conversion of the input high frequency digital orthogonal modulation signal in a fixed intermediate frequency band, a demodulator for orthogonally demodulating an intermediate frequency signal output from the conversion signal based on a fixed frequency, and a controller for matching a frequency of the oscillation signal to a central frequency of the intermediate frequency band based on a frequency control signal generated to perform an orthogonal detection process by the demodulator. The central frequency of the oscillation signal is offset to correspond to a carrier frequency of the digital data orthogonal modulation signal in the state that a plurality of digital orthogonal modulation signal is frequency division multiplexed in the intermediate frequency band.

Digital data receiver

In this invention, in arranging a balance type input terminal group or output terminal group in an integrated circuit, the formation is provided with one terminal for grounding and two signal terminals adjacent to this grounding terminal on both sides. In connecting the output terminal group of the first integrated circuit and the input terminal group of the second integrated circuit with each other in such formation, the grounding terminals themselves and signal terminals themselves are respectively connected in one to one. Further, in the integrated circuit formed as mentioned above, among the bonding wires connecting the balance type input terminal group or output terminal group with an electrode group of an inner chip, the two bonding wires connecting the chip with the signal terminals are wired symmetrically with the bonding wire connecting the chip with the grounding terminal as a center.

Integrated circuit and its connecting circuit

A broadband tuning circuit adapted for receiving both BS and CS broadcasting signals. The circuit includes an input circuit for receiving RF signals which associated with the BS and CS broadcasting signals, respectively, a splitter for splitting the RF signal to a low RF signal and a high RF signal, an oscillator for generating a local frequency signal, a first mixer for frequency converting the low RF signal to a first IF signal in the up-heterodyne fashion using the local frequency signal, a second mixer for frequency converting the high RF signal to a second IF signal in the down-heterodyne fashion using the local frequency signal, a selector for selecting either the first or the second IF signal and a demodulator for demodulating the information from the selected IF signal.

Broadband tuning circuit for receiving multi-channel signals over a

A band switching filter circuit includes a first filter for filtering an input signal with predetermined characteristics to output a first filtered signal, and a second filter for filtering the first filtered signal output from the first filter with frequency characteristics of a band narrower than that of the frequency characteristics of the first filter to output a second filtered signal. A switching circuit selects the first filtered signal output from the first filter or the second filtered signal output from the second filter in accordance with the level of an input control signal.

Band switching filter and satellite broadcast receiving system using the

A television tuner for use in a television receiver to receive a VHF band signal, a UHF band signal, and a satellite band signal converted from a received satellite signal, all of which are provided as a combined signal by a signal combiner. The television tuner includes an input terminal to receive the combined signal from the signal combiner, a first oscillator having a variable frequency, a first mixer to receive the combined signal and the output of the first oscillator to convert the combined signal into a first intermediate frequency signal if the VHF and UHF signals are to be utilized by the television receiver, or a second intermediate frequency signal if the satellite signal is to be utilized by the television receiver, first and second band-pass filters connected to the first mixer to receive first and second intermediate frequency signals, wherein the first band-pass filter is designed to pass the first intermediate frequency signal and the second band-pass filter is designed to pass the second intermediate frequency signal, and a processing circuit for processing the signals passed by the first and second band-pass filters to provide a standard VHF and UHF television signals and a frequency modulated satellite signal.

Growing community of inventors

Saitama, Japan

Hideki Oto