摘要:
A resonance circuit of a transmission line and a capacitor is connected to the base circuit of a transistor. The transmission line is shorter than one-quarter wavelength to make the resonant frequency of the resonant circuit higher than the frequency of a second harmonic. As a result, the angle of the reflection coefficient of the second harmonic when an input matching circuit side is viewed from the input terminal of the transistor ranges from 170° to 270° on a polar chart, and phase difference between the fundamental wave of the base current and the second harmonic decreases.
摘要:
A semiconductor chip for amplification is connected between input-side and output-side matching circuits, and each of matching circuits includes balanced circuits which receive signals different in phase by 180 degrees, divided from an input signal. The balanced circuits are connected at a virtual grounding point, which is used as a grounding point sensitive to RF characteristics in an IPD. Thus, a semiconductor device can be free from influence of variations of grounding wires and can be reduced in size, weight, and cost.
摘要:
A cascode circuit includes a first field effect transistor which has a source terminal grounded, a second field effect transistor which has a source terminal connected to a drain terminal of the first field effect transistor, and a first capacitor connected between the source terminal of the first field effect transistor and a gate terminal of the second field effect transistor. The first field effect transistor and the second field effect transistor are cascode-connected successively. A capacitance value of the first capacitor is 0.01 to 10 times that between the gate and source terminals of the second field effect transistor.
摘要:
A cascode circuit includes a first field effect transistor which has a source terminal grounded, a second field effect transistor which has a source terminal connected to a drain terminal of the first field effect transistor, and a first capacitor connected between the source terminal of the first field effect transistor and a gate terminal of the second field effect transistor. The first field effect transistor and the second field effect transistor are cascode-connected successively. A capacitance value of the first capacitor is 0.01 to 10 times that between the gate and source terminals of the second field effect transistor.
摘要:
A current limiting circuit is connected to the gate (input terminal) of an amplifying transistor. The current limiting circuit includes a protecting transistor, a first protecting resistor connecting the drain to the gate of the protecting transistor, and a second protecting resistor connecting the source to the gate of the protecting transistor. The current limiting circuit limits current, so that electric power larger than the maximum electric power allowable for the amplifying transistor does not pass.
摘要:
A current limiting circuit is connected to the gate (input terminal) of an amplifying transistor. The current limiting circuit includes a protecting transistor, a first protecting resistor connecting the drain to the gate of the protecting transistor, and a second protecting resistor connecting the source to the gate of the protecting transistor. The current limiting circuit limits current, so that electric power larger than the maximum electric power allowable for the amplifying transistor does not pass.
摘要:
A current limiting circuit is connected to the gate (input terminal) of an amplifying transistor. The current limiting circuit includes a protecting transistor, a first protecting resistor connecting the drain to the gate of the protecting transistor, and a second protecting resistor connecting the source to the gate of the protecting transistor. The current limiting circuit limits current, so that electric power larger than the maximum electric power allowable for the amplifying transistor does not pass.
摘要:
An internally impedance matched transistor circuit prevents low frequency oscillation during high frequency band operation. Field effect transistors and corresponding oscillation-preventing stabilization circuits are located in the same package with the stabilization circuits close to the corresponding field effect transistors. Each oscillation-preventing stabilization circuit includes a resistor and a capacitor connected in series.
摘要:
A cascode circuit for a high-gain or high-output millimeter-wave device that operates with stability. The cascode circuit including two cascode-connected transistors includes: a first high electron mobility transistor (HEMT) including a source that is grounded; a second HEMT including a source connected to a drain of the first HEMT; a reflection gain restricting resistance connected to the gate of the second HEMT, for restricting reflection gain; and an open stub connected to a side of the reflection gain restricting resistance which is opposite the side connected to the second HEMT, for short-circuiting high-frequency signals at a predetermined frequency and nearby frequencies.
摘要:
A voltage controlled oscillator having low phase noise and including: a variable resonator including a varactor and a control voltage terminal; and an open-end stub connected in parallel to the variable resonator, the open-end stub having a length shorter than or equal to an odd multiple of one quarter of a wavelength of a harmonic signal plus one sixteenth of the wavelength of the harmonic signal, and longer than or equal to an odd multiple of one quarter of the wavelength of the harmonic signal minus one sixteenth of the wavelength of the harmonic signal. In this structure, a high Q value is realized for a fundamental wave frequency. Fluctuation in a control voltage due to a harmonic signal is controlled.