A sense amplifier circuit comprising a first-, second-, third- and fourth-amplification-blocks, each amplification-block comprising: an amplification-block-transistor comprising and an amplification-block-resistor. The amplification-block-transistor includes: a first-conduction-channel-terminal, a second-conduction-channel-terminal that is connected to an amplification-block-output-node, and a control-terminal that is connected to an amplification-block-control-node. The sense amplifier circuit also comprises: an amplification-block-resistor connected in series between an amplification-block-input-node and the first-conduction-channel-terminal; a first-bias-voltage-source connected to the amplification-block-control-nodes of the first- and third-amplification-blocks, a second-bias-voltage-source connected to the amplification-block-control-nodes of the second- and fourth-amplification-blocks. The sense amplifier circuit also comprises: a first-common-mode-voltage-resistor connected in series between a first-sensed-output-terminal and a common-mode-voltage-node; and a second-common-mode-voltage-resistor connected in series between a second-sensed-output-terminal and the common-mode-voltage-node.

An efficient power supply with fast, wideband response has been disclosed. In one implementation, two switching regulators with different frequency responses are combined to provide wideband, efficient power.

A Class-D amplifier includes a plurality of power rails, a quantizer, and a driver stage. The quantizer and the driver stage have a combined gain. For each power rail of the plurality of power rails, the Class-D amplifier senses a voltage value for the power rail and determines a ramp amplitude based on the sensed voltage value. The Class-D amplifier concurrently switches from the driver stage using a first power rail to a second power rail of the plurality of power rails and switches from the quantizer using the ramp amplitude associated with the first power rail to using the ramp amplitude associated with the second power rail so that the combined gain is constant.

A system includes a power regulator coupled between a coil and a battery, wherein the power regulator is configured as a linear regulator when power is provided from the coil to the battery, and a current sense apparatus having two inputs coupled to an input and an output of the power regulator, respectively, wherein the current sense apparatus is configured to sense a bidirectional current flowing through the power regulator.

An electronic control apparatus that controls actuation of an inductive load includes: a current detector that detect current flowing through the inductive load and outputs a current detection signal in an analog signal; an analog-digital converter that takes in the current detection signal at a fetch timing, and converts the current detection signal into a current detection value; and a controller that calculates a current arithmetic value by executing arithmetic processing for the current detection value, and controls the current based on the current arithmetic value. The controller obtains a sample data value of the current arithmetic value for each of a plurality of fetch timings. The controller calculates a deflection between an ideal value of the current arithmetic value and the sample data value of the current arithmetic value, and learns the fetch timing, causing the deflection with the ideal value of the current arithmetic value to be minimized.

The present invention relates to a device for measuring an electric current generated by an acoustic amplifier in order to actuate an acoustic speaker comprising: a resistor (1) positioned in series between the amplifier and the speaker; a voltage-to-current converter (3), the inputs of which are connected to the terminals of the resistor (1), and which proportionally converts the difference in voltage across the terminals of the shunt to a signal current; a first current mirror (7), the input of which is connected to the output of the voltage-to-current converter (3) and the output of which is connected to a current-to-voltage converter (5); a constant bias current generator (9) connected to an input of the voltage-to-current converter (3) and the output of which is connected to the current-to-voltage converter (5) via a second current mirror (11), and capable of generating a bias current such that the device operates in linear mode and without saturation regardless of the electric current generated by the acoustic amplifier.

A power amplifier apparatus includes: an amplifier configured to amplify an input signal; a sensing circuit connected to the amplifier and configured to sense a bias of the amplifier; and a biasing circuit connected to the sensing circuit and configured to provide a biasing current to the amplifier, wherein the sensing circuit is configured to change the biasing current based on the bias of the amplifier.

Current monitoring techniques are included in an electronic system that provides power to a load from a power output stage that supplies power to a load. Multiple current control devices form the power output stage in series with multiple sense resistors that provide corresponding sense voltages indicative of current provided through the multiple current control devices to the load in the same or different time intervals. A calibration control circuit controls injection of current through the multiple sense resistors individually and measures the corresponding sense voltages generated by the current to determine resistance values of the multiple sense resistors. A correction subsystem computes a first ratio of a first resistance to a second resistance and a second ratio of a third resistance to a fourth resistance of the multiple sense resistors, and controls compensation for a difference between the first ratio and the second ratio to remove the measurement error.

In one embodiment, an RF generator includes an RF amplifier comprising an RF input, a DC input, and an RF output, the RF amplifier configured to receive at the RF input an RF signal from an RF source; receive at the DC input a DC voltage from a DC source; and provide an output power at the RF output; and a control unit operably coupled to the DC source and the RF source, the control unit configured to receive a power setpoint indicative of a desired output power at the RF output; determine a power dissipation at the RF generator; alter the DC voltage to decrease the power dissipation at the RF generator; and alter the RF signal to enable the output power at the RF output to be substantially equal to the power setpoint.

Circuitry, which includes a parallel amplifier and a switching supply, is disclosed. The parallel amplifier regulates a power supply output voltage based on a power supply control signal and provides a current sense signal, which is representative of a parallel amplifier output current from the parallel amplifier. The switching supply is coupled to the parallel amplifier. The switching supply provides a switching output voltage and makes an early determination of the switching output voltage using the current sense signal and the power supply control signal to at least partially compensate for delay in the switching supply. Additionally, the switching supply drives the parallel amplifier output current toward zero using the switching output voltage to increase efficiency.