Abstract: A circuit for protecting a node (201) in an electronic device (200) from an electrostatic discharge comprising: a voltage rail (206) arranged to provide an predetermined voltage when the device is powered; a first switching device (202) connected between said node (201) and ground (204); a second switching device (203) coupled to said node (201) and arranged to control the conductance of the first switching device (202) between said node (201) and ground (204); wherein, the second switching device (203) is configured to, irrespective of whether the device is powered or not powered, (a) hold the conductance of the first switching device (202) low when the potential difference between the node (201) and the voltage rail (206) is within an operating range, and (b) hold the conductance of the first switching device (202) high in response to an overvoltage at the node (201) so as to allow current to flow from the node (201) to ground (204).

Abstract: A circuit for protecting a node (201) in an electronic device (200) from an electrostatic discharge comprising: a voltage rail (206) arranged to provide an predetermined voltage when the device is powered; a first switching device (202) connected between said node (201) and ground (204); a second switching device (203) coupled to said node (201) and arranged to control the conductance of the first switching device (202) between said node (201) and ground (204); wherein, the second switching device (203) is configured to, irrespective of whether the device is powered or not powered, (a) hold the conductance of the first switching device (202) low when the potential difference between the node (201) and the voltage rail (206) is within an operating range, and (b) hold the conductance of the first switching device (202) high in response to an overvoltage at the node (201) so as to allow current to flow from the node (201) to ground (204).

Abstract: A variable gain amplifier circuit (200) comprising an amplifier element (202) having an input (208, 210) and an output (220, 222); a feedback loop (224, 226) having a feedback impedance (228, 230) connected between the input (208, 210) and output (232, 234) of the amplifier element (202); an input branch (212, 214) having an input resistance connected between an input of the variable gain amplifier circuit and the input (208, 210) of the amplifier element (202); and a plurality of switches for selecting a gain of the variable gain amplifier circuit (200); characterised in that the variable gain amplifier circuit (200) further comprises an intermediate element (204) having an input and an output, the input being connected to a node between one of the switches and the feedback impedance (228, 230), such that the output can provide a signal which can be used to attenuate a signal component in the output (220, 222) of the amplifier element (202) caused by a non-linearity in the plurality of switches.

Abstract: An electrical circuit comprises a source of an interferer signal; at least one component configured for using the signal; at least two electrically parallel conductive paths by which the signal can pass between the source and each of the at least one components; and a signal path selector configured to selectively enable the signal to pass from the source to the component by any of the at least two conductive paths and to, when one of the paths is enabled to carry the signal, disable each of the other at least two paths from carrying the signal.

Abstract: An electrical circuit comprises a source of an interferer signal; at least one component configured for using the signal; at least two electrically parallel conductive paths by which the signal can pass between the source and each of the at least one components; and a signal path selector configured to selectively enable the signal to pass from the source to the component by any of the at least two conductive paths and to, when one of the paths is enabled to carry the signal, disable each of the other at least two paths from carrying the signal.

Abstract: A mixer comprising a pair of low frequency mixer inputs, a pair of high frequency mixer inputs, a pair of mixer outputs, four switching units, each switching unit comprising a low frequency switching unit input, a high frequency switching unit input, a switching unit output, a node connected via a high pass filter to the respective high frequency switching unit input and via a low pass filter to the respective low frequency switching unit input and a switching device arranged to provide an output at the respective switching unit output in dependence on the voltage at the respective node, and comprising a first feedback loop responsive to the voltage at the first low frequency mixer input and arranged to regulate the current through the outputs of the first and second ones of the switching units so that the total current through the outputs of the first and second ones of the switching units is substantially proportional to the voltage at the first low frequency mixer input and a second feedback loop responsiv