Patent classifications
H03M1/066
Time-interleaved sampling circuits with randomized skipping
A time-interleaved sampling system includes an input signal having a time-varying analog value and a plurality of samplers. Each sampler is operable in a hold mode and a track mode. In the track mode, the samplers track the analog value of the input signal. In the hold mode, each sampler holds a respective analog value of the input signal that a respective sampler tracked immediately before entering the hold mode. The samplers enter the track mode in a predetermined sequence. After a last sampler in the predetermined sequence enters the track mode, the predetermined sequence is repeated in a loop. At random intervals, a skipped sampler in the predetermined sequence is bypassed from entering the track mode.
Analog-digital converter apparatus, sensor system and method for analog-digital conversion
Apparatuses and methods for analog-digital conversion and corresponding systems having a sensor and an apparatus of this type are provided. Demodulation is executed with no variable preamplification, followed by continuous-time analog-digital conversion, at least in time segments, which further employs chopper techniques.
Signal converter device, dynamic element matching circuit, and dynamic element matching method
A dynamic element method includes the following operations: summing up most significant bits of a digital code in a previous period and a pointer signal in the previous period, in order to generate a first signal; outputting the first signal to be an adjusted pointer signal according to a clock signal; and decoding the adjusted pointer signal to be control signals, in which the control signals are configured to set corresponding relations of components of a first digital to analog converter circuits and the most significant bits, in order to utilize the components to convert the most significant bits.
TECHNIQUES FOR LINEARIZING DIGITAL-TO-ANALOG CONVERTERS IN SIGMA-DELTA ANALOG-TO-DIGITAL CONVERTERS
The present disclosure relates generally to techniques for linearizing a digital-to-analog converter (DAC) in a continuous-time sigma-delta ADC. A sigma-delta ADC may be configured with a multibit quantizer for various applications. These applications may require wide-bandwidth high-resolution high-linearity power-efficient ADCs. In some embodiments, a mismatch of a multibit DAC might result in a bottleneck for achieving high linearity performance. Some linearization techniques may achieve high linearity performance. However, for a high-speed sigma-delta ADC, the DAC is configured to be part of a feedback loop. Existing linearization techniques often increase the delay in the feedback loop, which is not desired. Various aspects of the present disclosure provide improvement to linearization techniques by changing the references of the multibit quantizer. As a result, this reduces delay in the feedback loop of the sigma-delta modulator, which is beneficial for high-speed sigma-delta ADCs.
Techniques for linearizing digital-to-analog converters in sigma-delta analog-to-digital converters
The present disclosure relates generally to techniques for linearizing a digital-to-analog converter (DAC) in a continuous-time sigma-delta ADC. A sigma-delta ADC may be configured with a multibit quantizer for various applications. These applications may require wide-bandwidth high-resolution high-linearity power-efficient ADCs. In some embodiments, a mismatch of a multibit DAC might result in a bottleneck for achieving high linearity performance. Some linearization techniques may achieve high linearity performance. However, for a high-speed sigma-delta ADC, the DAC is configured to be part of a feedback loop. Existing linearization techniques often increase the delay in the feedback loop, which is not desired. Various aspects of the present disclosure provide improvement to linearization techniques by changing the references of the multibit quantizer. As a result, this reduces delay in the feedback loop of the sigma-delta modulator, which is beneficial for high-speed sigma-delta ADCs.
ANALOG-TO-DIGITAL CONVERSION CIRCUIT WITH IMPROVED LINEARITY
Herein disclosed is an example analog-to-digital converter (ADC) and methods that may be performed by the ADC. The ADC may derive a first code that approximates a combination of an analog input value of the ADC and a dither value for the ADC sampled on a capacitor array. The ADC may further derive a second code to represent a residue of the combination with respect to the first code applied to the capacitor array. The ADC may combine the numerical value of the first code and the numerical value of the second code to produce a combined code applied to the capacitor array for deriving a digital output code. Combining the numerical value of the first code and the numerical value of the second code in the digital domain can provide for greater analog-to-digital (A/D) conversion linearity.
TIME-INTERLEAVED SAMPLING CIRCUITS WITH RANDOMIZED SKIPPING
A time-interleaved sampling system includes an input signal having a time-varying analog value and a plurality of samplers. Each sampler is operable in a hold mode and a track mode. In the track mode, the samplers track the analog value of the input signal. In the hold mode, each sampler holds a respective analog value of the input signal that a respective sampler tracked immediately before entering the hold mode. The samplers enter the track mode in a predetermined sequence. After a last sampler in the predetermined sequence enters the track mode, the predetermined sequence is repeated in a loop. At random intervals, a skipped sampler in the predetermined sequence is bypassed from entering the track mode.
Temperature Sensor Semiconductor Device With Pair of Diodes and Feedback Loop
In an embodiment a semiconductor device includes a first diode and a second diode of specified sizing or biasing ratio, a negative voltage supply, a first resistor for a proportional to absolute temperature (PTAT) voltage drop, wherein the first diode is connected between the negative supply voltage and the first resistor, an array of dynamically matched current sources employing a dynamic element matching controller, wherein the first resistor is connected between the first diode and a first input of the array, and wherein the second diode is connected between the negative supply voltage and a second input of the array and a successive approximation register (SAR) feedback loop configured to drive a voltage difference to zero, wherein the voltage difference occurs between a first node present between the first resistor and the first input of the array and a second node present between the second diode and the second input of the array.
ANALOG TO DIGITAL CONVERTER
A multilevel analog to digital converter (ADC) is composed of noise shaping filter and multi-level quantizer, where said quantizer is made from an array of comparators, each coupled with one reference level, the said quantizer is coupled with a thermometric digital to analog converters (DAC) in the feedback path, the said DAC output is compared with ADC input and error is fed to noise shaping filter, said reference levels of each quantizer is generated from a digital to analog converter coupled with a digital quantizer reference controller and said digital quantizer reference controller is randomly changing the reference levels in a way that quantizer coupled DAC elements are indirectly randomised to improve the overall linearity and noise performance of the converter.
Segmented digital-to-analog converter
Disclosed examples include a segmented DAC circuit, including an R-2R resistor DAC to convert a first subword to a first analog output signal, an interpolation DAC to offset the first analog output signal based on an N-bit digital interpolation code signal to provide the analog output signal, and a Sigma Delta modulator to modulate a modulator code to provide the N-bit digital interpolation code signal that represents a value of second and third subwords.