Abstract:
A power amplifier of the present invention comprises MOS transistor (1) having a gate length of 180 nm or less, and output matching circuit (5) connected to a drain terminal of MOS transistor (1). Also, MOS transistor (1) is applied with voltage Vd_n normalized by a voltage value allowable in a DC state as a drain-source voltage, where Vd_n is in a range of 0.5 to 0.9. ZL (=RH+j·XL) represents a value equal to a load impedance when viewing the output matching circuit (5) from the drain terminal normalized by gate width W (mm) of MOS transistor (1), and a real part (RL) of the ZL is RL>0.64×Vd_n+0.19 (Ω· mm), and RL
Abstract:
The present invention solves characteristic deterioration caused by peaking and a ground inductance, and provides a transimpedance amplifier capable of achieving a higher gain and a wider band. For this purpose, the transimpedance amplifier is configured to include a feedback circuit having two or more extreme frequencies and having a filter characteristic which is flat with respect to frequencies in a frequency region not more than a smallest extreme frequency among the extreme frequencies, which is flat with respect to frequencies in a frequency region not less than a largest extreme frequency among the extreme frequencies, and which has at least one negative inclination portion with respect to frequencies in a frequency region between the smallest and largest extreme frequencies.
Abstract:
A semiconductor device having sufficiently high heat dissipation performance while inhibiting an increase in the area of a chip is provided. In semiconductor device 1, a plurality of HBTs 20 and a plurality of diodes 30 are one-dimensionally and alternately arranged on semiconductor substrate 10. Anode electrode 36 of diode 30 is connected to emitter electrode 27 of HBT 20 via common emitter wiring 42. Diode 30 works as heat dissipating elements dissipating to semiconductor substrate 10 the heat transmitted through common emitter wiring 42 from emitter electrode 27, and also works as a protection diode connected in parallel between an emitter and a collector of HBT 20.
Abstract:
A heterojunction bipolar transistor comprises a collector layer, a base layer, and an emitter layer stacked sequentially. The base layer comprises a first base layer joined to the collector layer in an inward base area directly below the emitter layer and a second base layer joined to the collector layer in an outward base area adjacent to the inward base area. The second base layer is formed of a semiconductor with a wider energy band gap than the collector layer.
Abstract:
A power amplifier of the present invention comprises MOS transistor (1) having a gate length of 180 nm or less, and output matching circuit (5) connected to a drain terminal of MOS transistor (1). Also, MOS transistor (1) is applied with voltage Vd_n normalized by a voltage value allowable in a DC state as a drain-source voltage, where Vd_n is in a range of 0.5 to 0.9. ZL (=RH+j·XL) represents a value equal to a load impedance when viewing the output matching circuit (5) from the drain terminal normalized by gate width W (mm) of MOS transistor (1), and a real part (RL) of the ZL is RL>0.64×Vd_n+0.19 (Ω·mm), and RL
Abstract:
A nitride semiconductor device having a high withstand voltage and being capable of reducing a leakage current, is provided. The nitride semiconductor device 30 of the present invention includes: a nitride semiconductor stack; an anode 36; and cathodes 37 and 38. The nitride semiconductor stack includes: a channel layer 33 and a wide bandgap layer 35, stacked in this order. The anode 36 forms a Schottky junction with the wide bandgap layer 35. The cathodes 37 and 38 are joined to the channel layer 33. The channel layer 33 is an n+-type nitride semiconductor layer. The bandgap of the wide bandgap layer 35 is wider than that of the channel layer 33.
Abstract:
Provided are a device model, a recording medium storing a program, a simulation circuit, device, and method that calculate a local temperature increase in an element. The device model according to the present invention is used for a semiconductor circuit simulation and has at least two model parameters. The model parameters include an electrical model describing temperature characteristics and a thermal model describing thermal characteristics and corresponding to the electrical model.
Abstract:
A semiconductor device of the present invention includes a systematic structure layer of first conductivity type and having a systematically arranged structure. The systematic structure layer is formed on a collector contact layer of first conductivity type, which is connected to collector electrodes. A compensation layer of first conductivity type is formed on the systematic structure layer. A collector layer of first conductivity type is formed on the compensation layer. A base layer is formed on the collector layer and connected to base electrodes. An emitter layer is formed on the base electrode and connected to an emitter electrode. The semiconductor device reduces collector resistance and thereby improves reliability.
Abstract:
Subcollector layers or emitter layers constituting a bipolar transistor having different thicknesses form a two-layered structure. A resistor layer is formed at the same as one of the subcollector layers or one of the emitter layers, from the same material as that of the subcollector layer or emitter layer. A resistor is formed by the resistor layer made of the same material as that of the subcollector layer or emitter layer. A resistor with a desired resistance can be integrally built into a semiconductor device without adversely affecting the characteristics of a bipolar transistor.
Abstract:
Provided are a device model, a recording medium storing a program, a simulation circuit, device, and method that calculate a local temperature increase in an element. The device model according to the present invention is used for a semiconductor circuit simulation and has at least two model parameters. The model parameters include an electrical model describing temperature characteristics and a thermal model describing thermal characteristics and corresponding to the electrical model.