An operational amplifier (OPAMP) is biased with a tail current that varies with temperature and process in order to compensate for variations in amplifier bandwidth. A proportional to absolute temperature (PTAT) current source generates a PTAT current producing a reference voltage. A voltage-to-current generator circuit utilizing a differential amplifier circuit converts the reference voltage to a reference current from which the tail current is derived. Resistors coupled to the PTAT current source and the voltage-to-current generator circuit have resistance values dependent on operating temperature, wherein such resistors are matching of the resistors used for a gain setting circuit of the OPAMP.

A power amplifier stage including multiple amplifier branch circuits, in which each amplifier branch circuit includes a cascode device, a source device, and a replica cascode device. The cascode device has current terminals coupled between an output node and an intermediate node, and has a control terminal receiving a corresponding activation signal. The source device has current terminals coupled between a supply reference node and the intermediate node, and has a control terminal receiving an input signal. The replica cascode device has current terminals coupled between a supply node and the intermediate node, and has a control terminal receiving a corresponding complementary activation signals. An output power level of the power amplifier stage is controlled by asserting a selected number of activation signals and corresponding complementary activation signals for activating a selected number of the amplifier branch circuits.

A multiphase DC-DC converter has two converter arrangements, each with a switching stage that has a switching node, an inductor, a converter output node, a high-side switch, and a low-side switch. Current sensing circuits detect the instantaneous current flowing through either the high-side or low-side switches, and signal time-averaging circuits produce time-averaged signals indicating the average current during a switch conduction interval. The time-averaged signals are added up and re-scaled based on the time period of the switching nodes' electrical coupling to the converter output nodes to generate an output signal for the average output current.

According to an embodiment, An integrated circuit comprising a first cascode radio frequency (RF) power amplifier that includes a first common source transistor having a gate configured to receive a first RF signal, and a source connected to a neutral point; a first common gate transistor having a gate and a drain connected to a power source node, and a source connected to a drain of the first common source transistor; and a first resistor coupled between a bulk of the first common gate transistor and a first bulk bias node configured to provide a voltage that is greater than or equal to a voltage at the source of the first common gate transistor, wherein the first resistor is configured to obtain a floating point.