A radio frequency (RF) switch includes switch transistors coupled in series. The RF switch includes a distributed gate bias network coupled to gate electrodes of the switch transistors. The RF switch also includes a distributed body bias network coupled to body electrodes of the switch transistors.

Embodiments described herein include radio frequency (RF) switches that may provide increased power handling capability. In general, the embodiments described herein can provide this increased power handling by equalizing the voltages across transistors when the RF switch is open. Specifically, the embodiments described herein can be implemented to equalize the source-drain voltages across each field effect transistor (FET) in a FET stack that occurs when the RF switch is open and not conducting current. This equalization can be provided by using one or more compensation circuits to couple one or more gates and transistor bodies in the FET stack in a way that at least partially compensates for the effects of parasitic leakage currents in the FET stack. In addition, multiple FET stacks are implemented in parallel in at least some switch branches to improve settling time for the branch.

The present invention discloses a signal output apparatus. Each of two output circuits includes an inverter including an input terminal and an output terminal, and a resistor coupled between the output terminal and a differential output terminal. Each of MOS capacitors is coupled between the output terminals. Under a first operation mode, two current supplying circuits are disabled. The input terminals respectively receive a high and a low state input voltages and the output terminals generate a low and a high state output voltages. The capacitances become larger than a predetermined level. Under a second operation mode, one of the current supplying circuits is enabled to output a supplying current to the differential output terminal. The input terminals receive the high state input voltage. The output terminals generate the low state output voltage. The capacitances become not larger than the predetermined level.

Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C.sup.3MOS) logic fabricated in conventional CMOS process technology. An entire family of logic elements including inverter/buffers, level shifters, NAND, NOR, XOR gates, latches, flip-flops and the like are implemented using C.sup.3MOS techniques. Optimum balance between power consumption and speed for each circuit application is achieve by combining high speed C.sup.3MOS logic with low power conventional CMOS logic. The combined C.sup.3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems.

Passive gate bias network topologies are implemented for stacked FET switch structures, which improve the settling time and low cut-off frequency for both DC and non-DC operation. DC capable stacked switch bias structures provide gate and bulk bias voltages, using input DC voltages, which are coupled to the gate terminals and the bulk terminals of the stacked switches. The DC coupling can be achieved using resistors, or a combination of resistors and diodes. An exemplary SPST switch includes a series stacked switch in combination with a shunt stacked switch, which can be controlled between alternating states. For low cut-off frequency improvement structures, an input signal is coupled to the gate terminals and bulk terminals of the switches in the stacked switches, using a DC block capacitor and resistors. The low cut-off of the bulk can be improved by connecting the bulk terminal of one switch to the opposite polarity switch.

Embodiments of a transistor control device for controlling a bi-directional power transistor are disclosed. In an embodiment, a transistor control device for controlling a bi-directional power transistor includes a resistor connectable to a body terminal of the bi-directional power transistor and a transistor body switch circuit connectable to the resistor, to a drain terminal of the bi-directional power transistor, and to a source terminal of the bi-directional power transistor. The transistor body switch circuit includes switch devices and alternating current (AC) capacitive voltage dividers connected to control terminals of the switch devices. The AC capacitive voltage dividers are configured to control the switch devices to switch a voltage of the body terminal of the bi-directional power transistor as a function of a voltage between the drain terminal of the bi-directional power transistor and the source terminal of the bi-directional power transistor.

The present invention provides a driving device and a control method. The driving device is configured to drive a power switch and includes a power supply, a first bridge arm coupled to the power supply, a second bridge arm coupled in parallel to the first bridge arm, and a resonant inductor. The first bridge arm includes a first switch and a second switch connected to a first midpoint, the second bridge arm comprises a first semiconductor element and a second semiconductor element connected to a second midpoint, and the resonant inductor is coupled between the first midpoint and the second midpoint. The control method includes turning on the first switch for a first period such that the power supply charges a gate electrode of the power switch; and in response to a decrease of a current of the resonant inductor to a first threshold value, turning on the first switch again for a second period such that a potential of the first midpoint is equal to a potential of the second midpoint.

An apparatus for reducing switching time of RF FET switching devices is described. A FET switch stack includes a stacked arrangement of FET switches and a plurality of gate feed arrangements, each coupled at a different height of the stacked arrangement. A circuital arrangement with a combination of a series RF FET switch and a shunt RF FET switch, each having a stack of FET switches, is also described. The shunt switch has one or more shunt gate feed arrangements with a number of bypass switches that is less than the number of FET switches in the shunt stack.

In a switching circuit, an inductance of an inductor of a shunt circuit is such that off capacitance of a second switching device that is in the off state when a first switching device is in the on state is used to define, in the shunt circuit, a series resonance circuit with a desired resonant frequency. Therefore, the frequency of an unnecessary signal to be attenuated is set to the resonant frequency of the series resonance circuit. Thus, the switching circuit achieves improved isolation characteristics with other circuits by attenuating the unnecessary signal.

RF switching circuitry includes one or more RF switching elements, a control signal input node, a common resistor, and common resistor bypass circuitry. The one or more RF switching elements are coupled in series between a switch input node and a switch output node. A state of each one of the one or more switching elements is determined based on a control signal. The control signal input node is configured to receive the control signal. The common resistor is coupled between the control signal input node and the one or more RF switching elements. The common resistor bypass circuitry is configured to receive the switching control signal and bypass the common resistor for a predetermined time period following one or more of a leading edge of the switching control signal and a falling edge of the switching control signal.