Abstract: Disclosed in the present invention are ABS rubber powder with a low impurity content, a preparation method therefor, and an ABS resin. The ABS rubber powder is treated by using the following steps: washing the ABS rubber powder with a washing solution I, and monitoring the content of soluble organic carbon in the ABS rubber powder until the content of soluble organic carbon in the ABS rubber powder is less than or equal to 9000 ppm, so as to obtain the ABS rubber powder with the low impurity content. In the present invention, by controlling the content of soluble organic carbon or the contents of soluble organic carbon and iron ions in the ABS powder, the ABS resin with a low yellow index of less than or equal to 18 is obtained.

Abstract: A ?-type voltage-controlled variable attenuator is disclosed. The variable attenuator may include variably resistive components in the series and shunt arms. The variably resistive components may be implemented as field effect transistors. The shunt arms may be coupled to the series arm, and the variable attenuator may lack capacitors between the series arm and shunt arms. The series arm and shunt arms may display variable resistances which, in combination, operate to provide a variable level of attenuation of an input signal. The variable attenuator may provide any level of attenuation of an input signal over a wide frequency range. The variable attenuator may be implemented as an integrated circuit.

Abstract: A ?-type voltage-controlled variable attenuator is disclosed. The variable attenuator may include variably resistive components in the series and shunt arms. The variably resistive components may be implemented as field effect transistors. The shunt arms may be coupled to the series arm, and the variable attenuator may lack capacitors between the series arm and shunt arms. The series arm and shunt arms may display variable resistances which, in combination, operate to provide a variable level of attenuation of an input signal. The variable attenuator may provide any level of attenuation of an input signal over a wide frequency range. The variable attenuator may be implemented as an integrated circuit.

Abstract: A transistor cell includes a first stage comprising a first transistor that is coupled to a RC filter arrangement. A second stage has a second transistor that is coupled to the first stage. The linearity of the transistor cell is improved by shifting the DC bias point so that the first stage is biased at a high quiescent current while the second stage is biased at a low quiescent current.

Abstract: A transistor cell includes a first stage comprising a first transistor that is coupled to a RC filter arrangement. A second stage has a second transistor that is coupled to the first stage. The linearity of the transistor cell is improved by shifting the DC bias point so that the first stage is biased at a high quiescent current while the second stage is biased at a low quiescent current.

Abstract: A high performance single-pole-double-throw (SPDT) Transmitter/Receiver (T/R) FET switch utilizes a plurality of multi-gate FETs in series to realize low insertion loss, low harmonic distortion and high power handling capabilities. The SPDT switch consists of an antenna port, a transmitter branch coupled to a transmitter port through a plurality of multi-gate FETs in series and a receiver branch coupled to a receiver port through a plurality of multi-gate FETs in series. When a high power signal passes from the transmitter port to the antenna port through the transmitter branch, the receiver branch is required to be shut off electrically to prevent the high power signal from leaking to receiver port. This leakage can degrade the isolation of the switch and cause harmonic distortion. Furthermore, the transmitter branch is required to provide a resistance as small as possible to reduce the power loss when it passes through the transmitter branch to the antenna port.

Abstract: A high performance single-pole-double-throw (SPDT) Transmitter/Receiver (T/R) FET switch utilizes a plurality of multi-gate FETs in series to realize low insertion loss, low harmonic distortion and high power handling capabilities. The SPDT switch consists of an antenna port, a transmitter branch coupled to a transmitter port through a plurality of multi-gate FETs in series and a receiver branch coupled to a receiver port through a plurality of multi-gate FETs in series. When a high power signal passes from the transmitter port to the antenna port through the transmitter branch, the receiver branch is required to be shut off electrically to prevent the high power signal from leaking to receiver port. This leakage can degrade the isolation of the switch and cause harmonic distortion. Furthermore, the transmitter branch is required to provide a resistance as small as possible to reduce the power loss when it passes through the transmitter branch to the antenna port.