Abstract: Apparatus and methods for biasing radio frequency (RF) switches to achieve fast switching are disclosed herein. In certain configurations, a switch bias circuit generates a switch control voltage for turning on or off a switch that handles RF signals. The switch bias circuit provides the switch control voltage to a control input of the switch by way of a resistor. Additionally, the switch bias circuit pulses the switch control voltage when turning on or off the switch to thereby shorten switching time. Thus, the switch can be turned on or off quickly, which allows the switch to be available for use soon after the state of the switch has been changed.

Abstract: Apparatus and methods for biasing radio frequency (RF) switches to achieve fast switching are disclosed herein. In certain configurations, a switch bias circuit generates a switch control voltage for turning on or off a switch that handles RF signals. The switch bias circuit provides the switch control voltage to a control input of the switch by way of a resistor. Additionally, the switch bias circuit pulses the switch control voltage when turning on or off the switch to thereby shorten switching time. Thus, the switch can be turned on or off quickly, which allows the switch to be available for use soon after the state of the switch has been changed.

Abstract: A high isolation wideband switch is disclosed. In one aspect, the switch includes an integrated circuit package having an integrated circuit die with a first plurality of leads that is positioned on a package substrate that has a second plurality of leads. The first leads of the integrated circuit die are connected to the second the leads of the package substrate via bond wires and a first electrical coupling occurs between the first leads and the integrated circuit die in response to an RF signal applied to the integrated circuit package. The bond wires have a second electrical coupling in response to the RF signal and the bond wires are arranged such that the second electrical coupling is matched to the first electrical coupling within a selected frequency band so as to reduce the overall electrical coupling of the integrated circuit package for RF signals within the selected frequency band.

Abstract: A control circuit is provided for controlling the voltage at the gate terminal of a field effect transistor acting as a switch. The voltage, at for example, the source terminal of the transistor can be provided to a low pass filter and is then voltage translated to provide the gate signal. The filtering can be arranged so as to compensate for the effect of parasitic capacitances within the transistor, thereby linearizing its frequency response. The voltage translation can help to limit voltage differences between the gate and channel of the transistor. This can be significant as relatively fast transistors, as might be used in microwave circuits, may fail with relatively modest voltages at their gates.

Abstract: Apparatus and methods for reducing glitches in digital step attenuators are disclosed. By configuring a multi-bit DSA such that an attenuation control block changes a plurality of control signals in a manner sequencing individual switches of the DSA, glitches can be reduced and RF signal behavior can be enhanced. The sequence, based upon a unit time delay, causes the transient attenuation value to be bounded between a minimum and maximum and can improve settling time.

Abstract: Apparatus and methods for radio frequency (RF) switches are provided herein. In certain implementations, an RF switching circuit includes an adaptive switch bias circuit that controls gate and/or channel voltages of one or more field effect transistor (FET) switches. Additionally, the adaptive switch bias circuit is powered by a power high supply voltage and a power low supply voltage, and can be used to selectively turn on or off the FET switches based on a state of one or more switch enable signals. The adaptive switch bias circuit adaptively biases that gate and/or channel voltages of the FET switches based on a voltage difference between the power high and power low supply voltages to provide switch biasing suitable for use with two or more different power supply voltage levels.

Abstract: Apparatus and methods for reducing glitches in digital step attenuators are disclosed. By configuring a multi-bit DSA such that an attenuation control block changes a plurality of control signals in a manner sequencing individual switches of the DSA, glitches can be reduced and RF signal behavior can be enhanced. The sequence, based upon a unit time delay, causes the transient attenuation value to be bounded between a minimum and maximum and can improve settling time.

Abstract: Apparatus and methods for radio frequency (RF) switches are provided herein. In certain implementations, an RF switching circuit includes an adaptive switch bias circuit that controls gate and/or channel voltages of one or more field effect transistor (FET) switches. Additionally, the adaptive switch bias circuit is powered by a power high supply voltage and a power low supply voltage, and can be used to selectively turn on or off the FET switches based on a state of one or more switch enable signals. The adaptive switch bias circuit adaptively biases that gate and/or channel voltages of the FET switches based on a voltage difference between the power high and power low supply voltages to provide switch biasing suitable for use with two or more different power supply voltage levels.

Abstract: A high isolation wideband switch is disclosed. In one aspect, the switch includes an integrated circuit package having an integrated circuit die with a first plurality of leads that is positioned on a package substrate that has a second plurality of leads. The first leads of the integrated circuit die are connected to the second the leads of the package substrate via bond wires and a first electrical coupling occurs between the first leads and the integrated circuit die in response to an RF signal applied to the integrated circuit package. The bond wires have a second electrical coupling in response to the RF signal and the bond wires are arranged such that the second electrical coupling is matched to the first electrical coupling within a selected frequency band so as to reduce the overall electrical coupling of the integrated circuit package for RF signals within the selected frequency band.

Abstract: Aspects of this disclosure relate to a termination circuit configured to mitigate crosstalk from a radio frequency (RF) input/output (I/O) path to a second I/O path, such as a digital I/O path. Such crosstalk can be due to coupling between adjacent bond wires, for example. The termination circuit can include a low impedance loss path, such as a series RC shunt circuit. According to certain embodiments, an electrostatic discharge (ESD) protection circuit can be in parallel with the termination circuit.

Abstract: Aspects of this disclosure relate to a termination circuit configured to mitigate crosstalk from a radio frequency (RF) input/output (I/O) path to a second I/O path, such as a digital I/O path. Such crosstalk can be due to coupling between adjacent bond wires, for example. The termination circuit can include a low impedance loss path, such as a series RC shunt circuit. According to certain embodiments, an electrostatic discharge (ESD) protection circuit can be in parallel with the termination circuit.