A digital-to-analog converter (DAC) is described. The DAC comprises a resistor having a resistance R and a capacitor having a capacitance C. The DAC comprises a first switching element configured, in response to a first control signal, to couple the capacitor to a first rail via a path having a resistance less than R and a second switching element configured, in response to a second control signal, to couple the capacitor to the first rail through the resistor. The DAC also comprises a third switching element configured, in response to a third control signal, to couple the capacitor to a second rail (8) via a path having a resistance less than R and a fourth switching element configured, in response to a responsive to a fourth control signal, to couple the capacitor to the second through the resistor. The capacitor can be quickly charged or discharged over a period less than RC or less than 0.7 RC. The DAC may comprise a first control element configured to switch on the second switching element before switching on the first switching element and a second control element configured to switch on the fourth switching element before switching on the third switching element.

Provided are, among other things, systems, apparatuses, methods and techniques for converting a discrete-time quantized signal into a continuous-time, continuously variable signal. An exemplary converter preferably includes: (1) multiple oversampling converters, each processing a different frequency band, operated in parallel; (2) multirate (i.e., polyphase) delta-sigma modulators (preferably second-order or higher); (3) multi-bit quantizers; (4) multi-bit-to-variable-level signal converters, such as resistor ladder networks or current source networks; (5) adaptive nonlinear, bit-mapping to compensate for mismatches in the multi-bit-to-variable-level signal converters (e.g., by mimicking such mismatches and then shifting the resulting noise to a frequently range where it will be filtered out by a corresponding bandpass (reconstruction) filter); (6) multi-band (e.g., programmable noise-transfer-function response) bandpass delta-sigma modulators; and/or (7) a digital pre-distortion linearizer (DPL) for canceling noise and distortion introduced by an analog signal bandpass (reconstruction) filter bank.

A method and apparatus for reducing global interconnect delay on a field programmable gate array (FPGA) on an integrated circuit die comprising coding with a digital to analog coder on the integrated circuit die successive groups of n digital bits into an 2.sup.n level voltage or current signal where n is an integer greater than or equal to 2; transmitting the voltage or current signal on a global interconnect on the integrated circuit die; receiving on the integrated circuit die the signal transmitted on the global interconnect; and decoding the received signal on the integrated circuit die to reconstitute the successive groups of digital bits.

A digital-to-analog converter (DAC) circuit includes a first DAC that produces a first analog output signal based upon a received multi-bit digital data and upon a received clock. A second DAC that produces a second analog output signal based upon the received multi-bit digital data and upon the received clock, wherein the first and second DACs are connected in parallel and process the same input signal comprising the multi-bit digital data. In one embodiment, the DACs produce differential signals. A low pass filter connected to receive the first and second analog outputs is configured to sum the first and second analog outputs and to filter the summed first and second analog outputs to produce an ingoing analog signal. An amplifier connected to receive the ingoing analog signal to produce an amplified ingoing analog signal.

Described herein are apparatus and methods for digitally enhancing digital-to-analog converter (DAC) resolution. A digitally enhanced DAC includes a decoder circuit configured to convert a N-bit input data to at least N code bits, a digital enhancement circuit configured to logically operate on a least significant bit (LSB) of the N-bit data, and a switching network including at least N DAC unit elements, where a least significant DAC unit element is controlled by the digital enhancement circuit to output a factored nominal current or voltage when a logical operation outputs a defined logic level for the LSB and to output a nominal current or voltage absent output of the defined logic level and a remaining DAC unit elements are controlled by a remaining code bits of the at least N code bits. This provides a N+1 bit resolution for the DAC without increasing the at least N DAC unit elements.

Systems, methods, and devices enhance management of components used in data converters. Methods include receiving an input at a data converter comprising a digital to analog converter (DAC), the digital to analog converter comprising a plurality of sensing elements, and performing, using the DAC, a first conversion operation based on the input and a first set of the plurality of sensing elements identified by a first pointer value. Methods also include determining a pointer increment value based, at least in part, on an output of the first conversion operation and a hysteresis threshold value, the pointer increment value being used to determine an amount by which the first pointer value is incremented, the hysteresis threshold value identifying a threshold for determination of the pointer increment value.

A phase interpolator providing a pair of differential outputs according to a plurality of inputs with a plurality of phases, the phase interpolator including: a main digital-to-analog converter (DAC) circuit configured to phase-interpolate a first input and a second input, which have orthogonal phases among the plurality of inputs, according to a main code to generate a main output signal; an auxiliary DAC circuit configured to phase-interpolate the first input and the second input according to an auxiliary code corresponding to the main code to generate an auxiliary output signal; and an output buffer configured to generate the pair of differential outputs according to a differential input based on a phase output signal, which is the sum of the main output signal and the auxiliary output signal.

A digital-to-analog converter circuit that creates an analog waveform from an input digital waveform. Operating the circuit comprises using the input digital waveform to 1) operate a charge control switch to set a charge time period, 2) operate a discharge control switch to set a discharge time period, 3) set a charge current magnitude using a charge gain, and 4) set a discharge current magnitude using a discharge gain. A charge source electrically charges a load capacitor during the charge time period (i.e., the charge mode). A discharge source electrically discharges the load capacitor during the discharge time period (i.e., the discharge mode). A circuit output transmits the analog waveform defined by the charge mode and the discharge mode. A charge current magnitude greater than the discharge current magnitude produces an upward-sloping analog waveform. A charge current magnitude less than the discharge current magnitude produces a downward-sloping analog waveform.

A method is disclosed for steering a physical analog system (e.g., an electric motor) using a discrete-level (e.g., binary) control signal. The discrete-level control signal is computed by an iterative scheme that can handle a long planning horizon. A preference for infrequent level switches can be taken into account. The quality of the fit to the target trajectory can be expressed not only by the quadratic error, but also by other norms. The method can be used also for digital-to-analog conversion.