FET amplifier

About: FET amplifier is a research topic. Over the lifetime, 7048 publications have been published within this topic receiving 77549 citations.

High frequency plasma power source and impedance matching device for supplying power to a semiconductor processing apparatus

Abstract: In a high frequency plasma power supply comprising a final stage push-pull amplifier 2 with each phase having a parallel combination of at least two FETs, an output transformer 5 having the connection of the phase outputs of the push-pull amplifier 2 to the opposite terminals of a primary winding with a neutral tap, and a low pass filler 6 allowing passage of substantially the fundamental frequency component from the secondary winding output of the output transformer 5, the high frequency power passing through the low pass filter being supplied between the electrodes of a plasma chamber 10 through an impedance matching circuit 9 having an impedance adjusting mechanism, the dc voltage Vds to be applied between the drain and source of each FET of each phase of the push-pull amplifier is adjusted to not more than about 30% of the dc absolute rated value and the turn ratio of the output transformer is 1:4, thereby supplying the power having the level necessary for plasma reaction.

A Ka-band HEMT MMIC 1 watt power amplifier

Abstract: A 34-36-GHz, 1-W, 9-dB-gain monolithic microwave integrated circuit (MMIC) power amplifier which utilizes 0.15- mu m pseudomorphic InGaAs-GaAs high-electron-mobility transistor (HEMT) process technology is discussed. Power amplifier sites across the wafer were fully characterized with an on-wafer pulsed large-signal S-parameter test set. Test results from these amplifier chips showed output powers >30 dBm, with >9-dB gain, and power-added efficiencies >20%. Overall chip size is 4.8 mm*2.3 mm. A two-stage power amplifier module using one chip to drive three chips has been developed. The resulting amplifier module has achieved 3-W output power and 17-dB gain from 34-36 GHz. >

Semiconductor relay circuit

Abstract: A semiconductor relay circuit includes a MOS FET (14) receiving a photovoltaic output generated across a photovoltaic diode array (13) responsive to a light signal from a light-emitting element (12), across gate and source electrodes (15,15a) of which MOS FET a control circuit (16) is connected to be at a high impedance state during the generation of the photovoltaic output but to be at a low impedance state upon disappearance of the output, and resistors (17,18) are inserted in series respectively in each of a path flowing a current from the photovoltaic diode array across the gate and source electrodes of the MOS FET and a path flowing a discharge current from a capacity across the gate and source electrodes of the MOS FET to the control circuit, whereby the setting of rise and fall of circuit output signals can be made easier.

A Wide-Band Transconductance Amplifier for Current Calibrations

Abstract: A wide-band transconductance amplifier for current calibrations is described. The amplifier will deliver a ground-referenced constant current of 5 A rms from dc to over 100 kHz. Its stable magnitude and phase permit it to be used in precise power calibration systems to provide the current component of a phantom power source. The amplifier also provides a ground-referenced voltage output of 1 V/A for monitoring the magnitude and phase of the output current.

Sliding power supply for RF power amplifier

Abstract: A sliding power supply for a radio frequency power amplifier provides power to the power amplifier that is indirectly controlled by the load impedance voltage standing wave ratio of the amplifier. The overall results being an enhancement or improvement in the efficiency of the RF power amplifier into a varying RF load mismatch.