摘要:
In a high frequency power amplifier circuit in which bias voltages are applied to the transistors for amplification by current mirroring, this invention enables preventing waveform distortion near the peak output power level by allowing sufficient idle currents to flow through the transistors for amplification, while enhancing the power efficiency in a low output power region. The power amplifier includes a detection circuit comprising a transistor for detection which receives the AC component of an input signal to the last-stage transistor for amplification at its control terminal, a current mirror circuit which mirrors current flowing through that transistor, and a current-voltage conversion means which converts current flowing in the slave side of the current mirror circuit into a voltage. In the detection circuit, a voltage from a bias circuit for generating the bias voltages for the transistors for amplification is applied to the control terminal of the transistor for detection and output of the detection circuit is applied to the control terminal of the last-stage transistor for amplification.
摘要:
In a high frequency power amplifier circuit in which bias voltages are applied to the transistors for amplification by current mirroring, The power amplifier includes a detection circuit including a transistor for detection which receives the AC component of an input signal to the last-stage transistor for amplification at its control terminal, a current mirror circuit which mirrors current flowing through that transistor, and a current-voltage converter which converts current flowing in the slave side of the current mirror circuit into a voltage. In the detection circuit, a voltage from a bias circuit for generating the bias voltages for the transistors for amplification is applied to the control terminal of the transistor for detection, and output of the detection circuit is applied to the control terminal of the last-stage transistor for amplification.
摘要:
A video camera in which an output signal from a solid-state image sensor is converted into the corresponding digital signal at the horizontal reading cycle of the output signal, and the digital signal is digital-processed with a first predetermined clock (fs) synchronous with the reading cycle to provide a luminance signal and a color difference signal. This video camera comprises data clock converter for latching the color signals; control circuit for detecting the phase of the changing point of the color signal generated; phase correction circuit for receiving the color signal after data clock conversion from said data clock converter, and producing a phase-corrected color difference signal by selecting, in accordance with said phase detecting signal from the control circuit, either one of the color difference signal having an intermediate phase obtained by interpolating the signals before and after the changing point of the received color signal and said color difference signal after data clock conversion; and modulation circuit for quadrature-balanced-modulating the color difference signal supplied from said phase correction circuit to provide a modulated color signal.
摘要:
In a high frequency power amplifier circuit in which bias voltages are applied to the transistors for amplification by current mirroring, The power amplifier includes a detection circuit including a transistor for detection which receives the AC component of an input signal to the last-stage transistor for amplification at its control terminal, a current mirror circuit which mirrors current flowing through that transistor, and a current-voltage converter which converts current flowing in the slave side of the current mirror circuit into a voltage. In the detection circuit, a voltage from a bias circuit for generating the bias voltages for the transistors for amplification is applied to the control terminal of the transistor for detections, and output of the detection circuit is applied to the control terminal of the last-stage transistor for amplification.
摘要:
An electronic component for high frequency power amplification realizes an improvement in switching spectrum characteristics. The gain of an amplifying NMOS transistor is controlled by a bias voltage on which a bias control voltage is reflected. Further, a threshold voltage compensator compensates for a variation in threshold voltage with variations in the manufacture of the amplifying NMOS transistor. The threshold voltage compensator includes an NMOS transistor formed in the same process specification as the amplifying NMOS transistor and converts a variation in current flowing through the NMOS transistor depending on the variation in the threshold voltage of the amplifying NMOS transistor to its corresponding voltage by a resistor to compensate for the bias voltage. It is thus possible to reduce variations in so-called precharge level brought to fixed output power in a region (0 dBm or less, for example) low in output power.
摘要:
An RF power module in which operating voltage is controlled by a control signal based on amplitude information includes a temperature detecting device which is provided over a semiconductor chip formed with an amplifying transistor or a semiconductor chip formed with a power source circuit; and a detector having a hysteresis characteristic which is provided over the semiconductor chip formed with the device or a different semiconductor chip, applies a bias to the temperature detecting device to compare the state of the device at two reference levels, outputs a signal indicating abnormality when judging that the temperature of the semiconductor chip formed with the temperature detecting device is above a predetermined temperature, and outputs a signal indicating normality when judging that the temperature of the semiconductor chip is below a second predetermined temperature lower than the predetermined temperature.
摘要:
An RF power module in which operating voltage is controlled by a control signal based on amplitude information includes a temperature detecting device which is provided over a semiconductor chip formed with an amplifying transistor or a semiconductor chip formed with a power source circuit; and a detector having a hysteresis characteristic which is provided over the semiconductor chip formed with the device or a different semiconductor chip, applies a bias to the temperature detecting device to compare the state of the device at two reference levels, outputs a signal indicating abnormality when judging that the temperature of the semiconductor chip formed with the temperature detecting device is above a predetermined temperature, and outputs a signal indicating normality when judging that the temperature of the semiconductor chip is below a second predetermined temperature lower than the predetermined temperature.
摘要:
Image data photographed by a video camera 20 is compressed by a compression and decompression circuit 5, the compressed image data is recorded in an incorporated type semiconductor memory 6 or disk-type memory 13 fixed in the video camera 20 and the recorded image data is transferred to an external recording device 23. Further, the external recording device 23 records the transferred image data in a data storage while it is being compressed. The video camera 20 receives, decompresses and converts into a television signal the compressed image data read by the external recording device 23 in a reproducing operation. A video camera system capable of recording and reproducing long hours of image data by using a video camera having an ultra small size comparable to that of an 8 mm video cassette can be realized by using such a construction.
摘要:
An electronic component for high frequency power amplification realizes an improvement in switching spectrum characteristics. The gain of an amplifying NMOS transistor is controlled by a bias voltage on which a bias control voltage is reflected. Further, a threshold voltage compensator compensates for a variation in threshold voltage with variations in the manufacture of the amplifying NMOS transistor. The threshold voltage compensator includes an NMOS transistor formed in the same process specification as the amplifying NMOS transistor and converts a variation in current flowing through the NMOS transistor depending on the variation in the threshold voltage of the amplifying NMOS transistor to its corresponding voltage by a resistor to compensate for the bias voltage. It is thus possible to reduce variations in so-called precharge level brought to fixed output power in a region (0 dBm or less, for example) low in output power.
摘要:
In a high frequency power amplifier circuit in which bias voltages are applied to the transistors for amplification by current mirroring, this invention enables preventing waveform distortion near the peak output power level by allowing sufficient idle currents to flow through the transistors for amplification, while enhancing the power efficiency in a low output power region. The power amplifier includes a detection circuit comprising a transistor for detection which receives the AC component of an input signal to the last-stage transistor for amplification at its control terminal, a current mirror circuit which mirrors current flowing through that transistor, and a current-voltage conversion means which converts current flowing in the slave side of the current mirror circuit into a voltage. In the detection circuit, a voltage from a bias circuit for generating the bias voltages for the transistors for amplification is applied to the control terminal of the transistor for detection and output of the detection circuit is applied to the control terminal of the last-stage transistor for amplification.