Patent classifications
H03M1/765
Interpolation digital-to-analog converter (DAC)
A integrated circuit device includes digital-to-analog converter (DAC) circuitry including a resistor DAC that includes a resistor-two-resistor DAC configured to receive a first sub-word that includes a most significant bit (MSB) of a digital input signal and to output an analog output signal representative of the first sub-word, a resistor ladder configured to receive the analog output signal and a second sub-word that includes an intermediate significant bit (ISB) of the digital input signal and to generate an analog interpolated signal. The resistor ladder includes a plurality of resistor elements connected in series with one another to define a plurality of tap nodes, wherein a respective tap node is arranged between every two adjacent ones of the resistor elements, and a switching circuit having plurality of switches, wherein each switch is configured to selectively connect a respective one of the tap nodes to an output of the resistor ladder to generate the analog interpolated signal.
DIGITAL-TO-ANALOG CONVERTER CLOCK TRACKING SYSTEMS AND METHODS
A number of unit cells of a digital-to-analog converter (DAC) may be simultaneously activated to generate an analog signal according to a decoded digital signal. Latches may be used at one or more levels of decoding and may be activated according to a clock signal to recapture the at least partially decoded data signals to maintain/improve the synchronicity of activation of the unit cells. However, the latches may consume additional power during operation. As such, clock tracking techniques such as static clock tracking, dynamic clock tracking, or differential clock tracking may be utilized to generate a clock path activation signal that gates the clock signal and determines which latches to ignore (e.g., leave inactive). In this manner, instead of activating each latch for every digital signal, clock tracking may be implemented to deactivate latches that do not provide useful updates to the decoded digital signal received at the unit cells.
Differential circuit calibration apparatus and method
An apparatus for calibrating a differential circuit that includes a differential integrator having an input, a gain, and an output connected to a comparator. The differential integrator output is chargeable to a threshold prior to an integration period. The differential integrator integrates the input during the integration period such that the differential integrator output goes toward zero from the threshold. The comparator detects the output of the differential integrator reaching zero. The apparatus includes a closed-loop gain trim circuit to perform a coarse calibration to adjust and set the gain of the differential integrator and a reference generator that generates the threshold to which the differential integrator output is pre-charged. The reference generator is trimmable during a fine calibration to adjust and set the threshold to correct for residual gain error in the differential circuit remaining after the coarse calibration is performed.
QUAD SWITCHED MULTIBIT DIGITAL TO ANALOG CONVERTER AND CONTINUOUS TIME SIGMA-DELTA MODULATOR
A quad signal generator circuit generates four 2.sup.N−1 bit control signals in response to a sampling clock and a 2.sup.N−1 bit thermometer coded signal. A digital-to-analog converter (DAC) circuit has 2.sup.N−1 unit resistor elements, with each unit resistor element including four switching circuits controlled by corresponding bits of the four 2.sup.N−1 bit control signals. Outputs of the 2.sup.N−1 unit resistor elements are summed to generate an analog output signal. The quad signal generator circuit controls generation of the four 2.sup.N−1 bit control signals such that all logic states of bits of the four 2.sup.N−1 bit control signals remain constant for at least a duration of one cycle of the sampling clock. The analog output signal may be a feedback signal in a sigma-delta analog-to-digital converter (ADC) circuit that includes a multi-bit quantization circuit operating to quantize a filtered loop signal to generate the 2.sup.N−1 bit thermometer coded signal.
DIGITAL-TO-ANALOG CONVERSION CIRCUIT, DIGITAL-TO-ANALOG CONVERSION METHOD, AND DISPLAY APPARATUS
Digital-to-analog conversion circuit, digital-to-analog conversion method, display apparatus are disclosed. Digital-to-analog conversion circuit may comprise: voltage dividing sub-circuit comprising M voltage dividing signal terminals; decoding sub-circuit comprising M input and output terminals, M input terminals electrically coupled to first to M.sup.th voltage dividing signal terminals of voltage dividing sub-circuit respectively, decoding sub-circuit configured to receive digital signal and select one of M input terminals to be electrically connected with output terminal according to digital signal; amplification sub-circuit comprising input and output terminals, input terminal of amplification sub-circuit electrically coupled to output terminal of decoding sub-circuit, amplification sub-circuit configured to amplify signal at its input terminal, output analog gray-scale voltage at output terminal, voltage dividing signal at voltage dividing signal terminal is less than or equal to ½ of maximum load voltage at output terminal of digital-to-analog conversion circuit, amplification sub-circuit has amplification coefficient N greater than or equal to 2.
DAC and oscillation circuit
The present technology relates to a DAC (Digital to Analog Converter) and an oscillation circuit that allow widening of a range of a voltage to be output from the DAC. A plurality of first switches is connected to a voltage-dividing resistor and each configured to output, as a first voltage, a voltage at a corresponding one of connection points between the voltage-dividing resistor and the plurality of first switches. A plurality of second switches is connected to the voltage-dividing resistor and each configured to output, as a second voltage, a voltage at a corresponding one of connection points between the voltage-dividing resistor and the plurality of second switches. The present technology can be applied to, for example, a VCO (Voltage-Controlled Oscillator) and the like that oscillates a signal with a frequency according to a voltage to be output from a DAC.
Voltage detector
A device for monitoring voltage in a battery-operated system, the device including: a ladder selector configured to select between a first resistive ladder and a second resistive ladder; the first resistive ladder includes: a first string of resistors coupled between a sensing input node and a first node of the ladder selector; and a first set of transistors configured to tap intermediate nodes of a set of resistors in the first string of resistors; the second resistive ladder includes: a second string of resistors coupled between the sensing input node and a second node of the ladder selector; and a second set of transistors configured to tap intermediate nodes of a set of resistors in the second string of resistors; and wherein a selected transistor in one of the first set of transistors or the second set of transistors is turned on, and non-selected transistors of the first set of transistors and the second set of transistors are turned off to set a threshold voltage for a sensing output node.
Approximate nonlinear digital data conversion for small size multiply-accumulate in artificial intelligence
Multipliers and Multiply-Accumulate (MAC) circuits are fundamental building blocks in signal processing, including in emerging applications such as machine learning (ML) and artificial intelligence (AI) that predominantly utilize digital-mode multipliers and MACs. Generally, digital multipliers and MACs can operate at high speed with high resolution, and synchronously. As the resolution and speed of digital multipliers and MACs increase, generally the dynamic power consumption and chip size of digital implementations increases substantially that makes them impractical for some ML and AI segments, including in portable, mobile, near edge, or near sensor applications. The multipliers and MACs utilizing the disclosed current mode data-converters are manufacturable in main-stream digital CMOS process, and they can have medium to high resolutions, capable of low power consumptions, having low sensitivity to power supply and temperature variations, as well as operating asynchronously, which makes them suitable for high-volume, low cost, and low power ML and AI applications.
Digital-to-analog converter to reduce noise generated by a quiescent current
A digital-to-analog converter includes a first current source module configured to supply a current I.sub.1 to the digital-to-analog converter, a first switch control module configured to control connection or disconnection between each branch and a trans-impedance amplifier in the digital-to-analog converter based on a to-be-converted digital signal, where the current I.sub.1 supplied by the first current source module flows to the trans-impedance amplifier through a connected branch, and the trans-impedance amplifier is configured to convert the current I.sub.1 supplied by the first current source module into an analog voltage and output the analog voltage.
CONSTANT CURRENT DIGITAL TO ANALOG CONVERTER SYSTEMS AND METHODS
An electronic device may include a digital to analog converter receiving digital signals and outputting analog signals based on the received digital signals. The electronic device may also include a power source to supply current to the digital to analog converter. The digital to analog converter may include a first resistor ladder section to electrically couple an output node of the digital to analog converter to the power source via a first number of resistors in series. The digital to analog converter may also include a second resistor ladder section to electrically couple the output node to a reference voltage via a second number of resistors in series. The sum of the first number of resistors in series and the second number of resistors in series may be the same for each of the different analog signals.