In accordance with an embodiment, a method for digital-to-analog conversion includes: mapping a uniformly distributed input code to a non-uniformly distributed input code of a switched capacitor digital-to-analog converter (DAC), the non-uniformly distributed input code including a most significant code (MSC) and a least significant code (LSC); transferring a first charge from a set of DAC capacitors to a charge accumulator based on the MSC; forming a second charge based on the LSC; and transferring the second charge from the set of DAC capacitors to the charge accumulator, where each capacitor of the set of DAC capacitors is used for each value of the non-uniformly distributed input code, each capacitor of the set of DAC capacitors provides a same corresponding nominal charge within each value of the non-uniformly distributed input code, and where the same nominal charge is proportional to a value of the non-uniformly distributed input code.

A waveform shaping circuit includes a capacitor, an impedance element, a switch circuit, and a switch control circuit. Opposite ends of the capacitor are connected to the input and output, respectively. One end of the impedance element supplies a target constant voltage to the output end of the capacitor. The switch circuit has a switch without a diode. When on, the switch applies the target constant voltage to the output. When off, it does not. The switch control circuit switches the switch on during a high voltage period in an AC component of an input pulse signal and switches the switch off during a low voltage period of the AC component. The circuit shapes the input pulse signal into an output pulse signal whose peak-to-peak voltage is equivalent to a peak-to-peak voltage of the AC component and whose voltage during the high voltage period is at the target constant voltage.

A waveform shaping circuit includes a capacitor, an impedance element, a switch circuit, and a switch control circuit. Opposite ends of the capacitor are connected to the input and output, respectively. One end of the impedance element supplies a target constant voltage to the output end of the capacitor. The switch circuit has a switch without a diode. When on, the switch applies the target constant voltage to the output. When off, it does not. The switch control circuit switches the switch on during a high voltage period in an AC component of an input pulse signal and switches the switch off during a low voltage period of the AC component. The circuit shapes the input pulse signal into an output pulse signal whose peak-to-peak voltage is equivalent to a peak-to-peak voltage of the AC component and whose voltage during the high voltage period is at the target constant voltage.

Systems and methods for facilitating intercom communication for one or more quick-service restaurant drive-throughs are disclosed. Exemplary implementations may: capture sound from a customer placing an order; generate order information signals that represent the captured sound; encode signals to form order data packets; transmit the order data packets to a base station through a single pair of wires that is also used to provide power; decode information from the order data packets; and generate order sound based on the decoded information, such that the generated order sound is audible to a staff member of the quick service restaurant through a headset.

Systems and methods for facilitating intercom communication for one or more quick-service restaurant drive-throughs are disclosed. Exemplary implementations may: capture sound from a customer placing an order; generate order information signals that represent the captured sound; encode signals to form order data packets; transmit the order data packets to a base station through a single pair of wires that is also used to provide power; decode information from the order data packets; and generate order sound based on the decoded information, such that the generated order sound is audible to a staff member of the quick service restaurant through a headset.

A voltage ladder is used to generate reference voltages. The voltage ladder is used by multiple digital-to-analog converters (DACs). In particular, the voltage ladder is used by multiple pulse-width modulation (PWM) DACs. Having multiple DACs utilize a common voltage ladder for their reference voltages reduces mismatched output voltages between DACs. Having multiple DACs utilize the common voltage ladder helps ensure that the reference voltages used by different DACs are not affected by process, voltage, and/or temperature variations in the reference voltages that would occur when using different voltage ladders for each DAC.

A communication system includes a first system input adapted to be coupled to a DC transient current transitioning between a starting level and a target level on a pseudo-sinusoidal path and incudes a second system input adapted to be coupled to a HART signal. The system includes an adder circuit having an output, a first adder input coupled to the first system input and a second adder input coupled to the second system input. The adder circuit provides a superimposed signal comprising the HART signal and the DC transient current.

A communication system includes a first system input adapted to be coupled to a DC transient current transitioning between a starting level and a target level on a pseudo-sinusoidal path and incudes a second system input adapted to be coupled to a HART signal. The system includes an adder circuit having an output, a first adder input coupled to the first system input and a second adder input coupled to the second system input. The adder circuit provides a superimposed signal comprising the HART signal and the DC transient current.

The present disclosure provides a device and method of generating a nonlinear waveform signal dissipating low power and operating at a high speed. The device includes: a digital preprocessing unit configured to quantize an effective input signal to generate a linear data signal and a residual signal that is a difference between the effective input signal and the linear data signal; a nonlinear digital-to-analog conversion circuit (DAC) having a nonlinear relationship between an input and an output and configured to convert the linear data signal into a first analog signal; a linear interpolation DAC configured to convert the residual signal into a second analog signal to enable a generation of a converted analog signal by an addition of the second analog signal to the first analog signal; and an output circuit configured to output the converted analog signal as a nonlinear waveform signal.

The present disclosure provides a device and method of generating a nonlinear waveform signal dissipating low power and operating at a high speed. The device includes: a digital preprocessing unit configured to quantize an effective input signal to generate a linear data signal and a residual signal that is a difference between the effective input signal and the linear data signal; a nonlinear digital-to-analog conversion circuit (DAC) having a nonlinear relationship between an input and an output and configured to convert the linear data signal into a first analog signal; a linear interpolation DAC configured to convert the residual signal into a second analog signal to enable a generation of a converted analog signal by an addition of the second analog signal to the first analog signal; and an output circuit configured to output the converted analog signal as a nonlinear waveform signal.