A controllable temperature coefficient bias (CTCB) circuit is disclosed. The CTCB circuit can provide a bias to an amplifier. The CTCB circuit includes a variable with temperature (VWT) circuit having a reference circuit and a control circuit. The control circuit has a control output, a first current control element and a second current control element. Each current control element has a controllable resistance. One of the two current control elements may have a relatively high temperature coefficient and another a relatively low temperature coefficient. A controllable resistance of one of the current control elements increases when the controllable resistance of the other current control element decreases. However, the total resistance of the current control circuit remains constant with a constant temperature. The VWT circuit has an output with a temperature coefficient that is determined by the relative amount of current that flows through each current control element of the control circuit. A Current Digital to Analog Converter (IDAC) scales the output of the VWT and provides the scaled output to an amplifier bias input.

Technologies for the reduction of memory effects in a capacitor are disclosed. In the illustrative embodiment, a companion chip is connected to a quantum processor. The companion chip provides voltages to gates of qubits on the quantum processor. The companion chip includes an array of capacitors that can be charged to a voltage based on a voltage to be applied to a gate of the quantum processor. The capacitors in the array of capacitors are connected to the gate one at a time, charging up a parasitic capacitance. As more capacitors are switched, the voltage on the gate approaches a target voltage with an exponentially-decreasing voltage error.

Technologies for the reduction of memory effects in a capacitor are disclosed. In the illustrative embodiment, a companion chip is connected to a quantum processor. The companion chip provides voltages to gates of qubits on the quantum processor. The companion chip includes an array of capacitors that can be charged to a voltage based on a voltage to be applied to a gate of the quantum processor. The capacitors in the array of capacitors are connected to the gate one at a time, charging up a parasitic capacitance. As more capacitors are switched, the voltage on the gate approaches a target voltage with an exponentially-decreasing voltage error.

A digital-to-analog converter may include an integrator, an input network comprising a plurality of parallel taps, each member of the plurality of parallel taps having a signal delay such that at least two of the signal delays of the members of the plurality of parallel taps are different, and wherein each member of the plurality of parallel taps is coupled between an input of the digital-to-analog converter and an input of the integrator, and control circuitry configured to selectively enable and disable particular members of the plurality of parallel taps in order to program an effective input resistance of the input network to control an analog gain of the digital-to-analog converter, such that the control circuitry enables an even number of members at a time, with half of such enabled members in a first group and half of such enabled members in a second group.

A control circuit and a method of calibrating a signal converter (such as DAC) are disclosed. The control circuit can be an existing control circuit, so no additional calibration circuit is required and the circuit area can be reduced. The control circuit can be an embedded microcontroller or other type of microcontroller. In general, the microcontroller includes an analog comparator and an arithmetic unit. With the combination of using the arithmetic unit to execute firmware program codes and using of the analog comparator, the control circuit is able to calibrate the signal converter.

A numerically controlled oscillator system for maintaining a consistent phase reference while switching data rates may include a numerically controlled oscillator (NCO) circuit. The NCO circuit may include a phase accumulator, a phase-to-signal mapping circuit, and a first free-running counter. The phase accumulator may receive a new phase value as an input in response to an update signal. The phase-to-signal mapping circuit may map a value from the phase accumulator to a periodic signal. The first free-running counter may continue counting, without being reset, while the numerically controlled oscillator system is switching digital data rates. The first free-running counter may be configured to provide the new phase value to the phase accumulator using a representation of a counter value of the first free-running counter and a frequency tuning word defined by a representation of a frequency of the periodic signal.

Examples of amplifiers and associated control blocks control analog and digital gains of such an amplifier to maintain a ripple voltage at the input/virtual terminals of an internal integrator below an upper limit. Such an example amplifier comprises digital and analog processing blocks. The digital processing block receives a digital audio signal and also includes a digital gain component. The analog processing block includes an analog gain component and an output stage having a supply voltage terminal. A boost controller receives the digital audio signal, and has a digital output and a boost voltage output to output a boost voltage. A digital controller receives the digital audio signal, and has a first digital input coupled to the digital output of the boost controller and a second digital input to receive a measurement value indicative of the outputted boost voltage. Based on its inputs, the digital controller controls the digital and analog gain components.

Examples of amplifiers and associated control blocks control analog and digital gains of such an amplifier to maintain a ripple voltage at the input/virtual terminals of an internal integrator below an upper limit. Such an example amplifier comprises digital and analog processing blocks. The digital processing block receives a digital audio signal and also includes a digital gain component. The analog processing block includes an analog gain component and an output stage having a supply voltage terminal. A boost controller receives the digital audio signal, and has a digital output and a boost voltage output to output a boost voltage. A digital controller receives the digital audio signal, and has a first digital input coupled to the digital output of the boost controller and a second digital input to receive a measurement value indicative of the outputted boost voltage. Based on its inputs, the digital controller controls the digital and analog gain components.

An inductive current digital-to-analog converter (DAC) includes: a power supply input adapted to be coupled to a power supply; a load terminal adapted to be coupled to a load; an inductor between the power supply input and the load terminal; and inductor current control circuitry. The inductor current control circuitry has: a sense signal input configured to receive a sense signal representative of the inductor current; a control code input configured to receive a control code; a set of switches having respective control terminals; and a set of control circuit outputs coupled to the respective control terminals of the set of switches. The inductor current control circuitry is configured to adjust control signals provided to the set of control circuit outputs based on the sense signal and the control code.

A digital-to-analog converter includes a current cell array including a plurality of current cells, each current cell of the plurality of current cells being configured to generate a current of a same magnitude; a first pattern connecting first current cells, among the plurality of current cells, arranged along a diagonal line of the current cell array; a second pattern connecting second current cells, among the plurality of current cells, arranged along a first oblique line parallel to the diagonal line; and a third pattern connecting third current cells, among the plurality of current cells, arranged along a second oblique line parallel to the diagonal line, the third pattern being electrically connected to the second pattern, wherein the diagonal line is between the first oblique line and the second oblique line.