Improved offline calibration for DAC mismatch in low OSR Sigma Delta ADCs with distributed feedback, " in Proc. Abstract—We present an offline calibration method to correct the non-linearity due to DAC element mismatch in distributed feedback SigmaDelta-modulation A/D-converters. The improvement over previous methods is that not only the first feedback DAC is calibrated, but also the DACs that ...

A constant-envelope, continuous phase modulation architecture is presented in which a sigma-delta modulator is combined with an open-loop modulator. Compared to existing architectures, Σ∆ based open-loop modulation can be implemented with minimal analog circuitry. The architecture is demonstrated with a discrete implementation performing frequency modulation at a carrier frequency of 120 MHz. B...

A major drawback of delta-sigma modulation is the high oversampling ratios required, especially for single-bit quantization. Accordingly, much of the research in the area has focused on lowering the sampling rate through various parallelization approaches. However, this research has been overwhelmingly concentrated on continuous and discrete-time analog modulator implementations for A/D convert...

An all-digital PWM-based delta-sigma (ΔΣ) ADC is proposed. This system takes advantages of the duration of a pulse, rather than voltage or current, as the analog operand used in its closed-loop operation. Unlike VCO-based ADCs, this ADC as a linear input sampling stage with adequate uncalibrated performance. Furthermore, the architecture allows inherently matched multi-bit quantizer/DAC blocks ...

issue of the stimulation of charge-pump phase-locked loops for built-in self-test applications. It is shown that three nodes of the PLL qualify for test signal injection. The hardware and methodology for each are discussed. In particular, a comprehensive explanation of the use of delta-sigma modulation in the time domain is provided. Furthermore, implementation issues of analog tests with signa...

Bilirubin is sensitive to light and oxygen. The rate of photodegradation of unconjugated bilirubin (Bu) was nearly twice that of monoconjugated bilirubin (mBc) and three fold that of diconjugated bilirubin (dBc); delta bilirubin (Bd) was the most stable against photoirradiation. In the presence of serum albumin, conjugated bilirubin (Bc: i.e., mBc and dBc) showed the highest rate of oxidation b...

A third-order sigma-delta (Σ -Δ ) modulator implementation in a Digital Power Amplifier is presented in this paper. The operation is obtained by using a novel combination of architectural features, proper circuit structure selections, specific clocking strategies, and efficient circuit optimization algorithms. Measurement results from fabricated CMOS chip prototypes show a good match with simul...

Vehicle change in velocity, often referred to as delta-V, is a widely used measure of crash severity. The National Highway Traffic Safety Administration (NHTSA) uses the WinSMASH computer code to estimate delta-V in several of its in-depth crash databases. This study examined the accuracy of WinSMASH longitudinal delta-V estimates in 140 rear crashes by comparison with direct measurements of de...