Abstract: Selectable sizes for a local oscillator (LO) buffer and mixer are disclosed. In an embodiment, LO buffer and/or mixer size may be increased when a receiver operates in a high gain mode, while LO buffer and/or mixer size may be decreased when the receiver operates in a low gain mode. In an embodiment, LO buffer and mixer sizes are increased and decreased in lock step. Circuit topologies and control schemes for specific embodiments of LO buffers and mixers having adjustable size are disclosed.

Abstract: Selectable sizes for a local oscillator (LO) buffer and mixer are disclosed. In an exemplary embodiment, LO buffer and/or mixer size may be increased when a receiver or transmitter operates in a high gain mode, while LO buffer and/or mixer size may be decreased when the receiver or transmitter operates in a low gain mode. In an exemplary embodiment, LO buffer and mixer sizes are increased and decreased in lock step. Circuit topologies and control schemes for specific exemplary embodiments of LO buffers and mixers having adjustable size are disclosed.

Abstract: Attenuation cell comprising first and second differential pairs of bipolar transistors. A gain control device applies a voltage VA?VB between the bases of both differential pairs and comprises a set of three diodes in which a current IA, a current IB and the sum IA+IB of both preceding currents flow, respectively. The two diodes seeing current IB and IA+IB generate a voltage, respectively VB and VC, and the difference between these two voltages is used to generate a value Iz used in a control loop. A desired value Vct is transformed into information Ix, then into information Iy proportional to absolute temperature T, and an error amplifier uses information Iy?Iz and generates currents IA and IB by minimizing this difference.

Abstract: Attenuation cell comprising first and second differential pairs of bipolar transistors. A gain control device applies a voltage VA-VB between the bases of both differential pairs and comprises a set of three diodes in which a current IA, a current IB and the sum IA+IB of both preceding currents flow, respectively. The two diodes seeing current IB and IA+IB generate a voltage, respectively VB and VC, and the difference between these two voltages is used to generate a value Iz used in a control loop. A desired value Vct is transformed into information Ix, then into information Iy proportional to absolute temperature T, and an error amplifier uses information Iy-Iz and generates currents IA and IB by minimizing this difference.

Abstract: An integrated circuit including an output pad, an output block coupled to the output pad via a capacitor, a first one-way conduction element for connecting the pad to a supply line when the voltage on the pad exceeds the voltage of the supply line by a first threshold voltage, a second one-way conduction element for connecting the pad to the circuit ground when the voltage on the pad is smaller than the ground voltage by a second threshold voltage, a resistor coupled on the one hand to the output pad and on the other hand to the supply line via a switch which is turned off when the circuit is idle and which is turned on when the circuit is in a normal operating mode.

Abstract: A biasing device includes closed-loop transconductance slaving circuit, able to slave the time average of the base/emitter or gate/source voltage of the amplifier transistor (Q1) to a reference voltage corresponding to a desired quiescent current for the transistor. Moreover, viewed from the base or gate of the amplifier transistor (Q1), the impedance of the base/emitter or gate/source circuit is small at low frequency, and large with respect to the impedance of the radio frequency source within the radio frequency range of the signal. The device can be incorporated in a mobile terminal, such as a cellular mobile phone.

Abstract: A biasing device includes closed-loop transconductance slaving circuit, able to slave the time average of the base/emitter or gate/source voltage of the amplifier transistor (Q1) to a reference voltage corresponding to a desired quiescent current for the transistor. Moreover, viewed from the base or gate of the amplifier transistor (Q1), the impedance of the base/emitter or gate/source circuit is small at low frequency, and large with respect to the impedance of the radio frequency source within the radio frequency range of the signal. The device can be incorporated in a mobile terminal, such as a cellular mobile phone.

Abstract: An integrated circuit including an output pad, an output block coupled to the output pad via a capacitor, a first one-way conduction element for connecting the pad to a supply line when the voltage on the pad exceeds the voltage of the supply line by a first threshold voltage, a second one-way conduction element for connecting the pad to the circuit ground when the voltage on the pad is smaller than the ground voltage by a second threshold voltage, a resistor coupled on the one hand to the output pad and on the other hand to the supply line via a switch which is turned off when the circuit is idle and which is turned on when the circuit is in a normal operating mode.