This paper reported extensive study and research proposal of Post simulation and behavioral modeling of Second Order sigma-delta modulator BIST technique in which include non-ideality factor such as offset error and clock jitters. For the test of the digital parts, BIST techniques have been developed and are broadly implemented in current chips. BIST technique not only avoids depending on the o...

AND JEFFREY L. CUTCHER Motorola Inc. Plantation, FL Fractional-N synthesizers are highly desirable in communication systems because of their high frequency resolution output. This resolution is made possible by dithering the divide value using the output of a sigma-delta modulator. A typical sigma-delta fractional-N frequency synthesizer is shown in Figure 1. The tri-state phase frequency detec...

Adaptive noise cancellation (ANC) technique can removes thermal and shaped wideband quantization noise from the output of sigma-delta modulator and improves SNR and SFDR ratios. ANC filter more than desired signal passes harmonics of input signal caused by analog element such as operational amplifier of the integrator without any suppression and this issue causes less increment in SNR and SFDR ...

Recent work has shown that high-order single-bit sigma-delta modulators suffer from lowlevel artifacts such as idle tones and noise modulation. Techniques that have been proposed to reduce or eliminate these errors include the application of dither inside the one-bit quantiser loop, and selecting a loop filter which makes the modulator chaotic. This paper compares the efficacy of these two appr...

Due to limited battery capacity, electronics in biomedical devices require low power consumption. On the other hand, biomedical devices that integrate multiple functions like sensing, amplification, signal conditioning, signal processing, data storage, etc. have put a greater constraint on power consumption for each functional unit. This paper presents a low power design of a decimator for a si...

A phase-locked loop (PLL) with frequency resolution in steps smaller than the reference oscillator is often wanted. Although this can be accomplished with a fractional-N PLL, in which the divide ratio is varied between N and N+1 at a defined rate, this technique generates undesired spurs. An alternative is to use a delta-sigma modulator in which the divide ratio (divisor) is dithered, eliminati...

The purpose of this paper is to present several filter topologies used for decimation of sigma delta modulated digital signals in order to choose the optimised filter architecture with regards to an efficient implementation. The filter is suited for data conversion and measurement applications. A second order 1-bit sigma delta modulator will be considered as the front-end A/D converter. The sub...

Oversampling Sigma Delta ADC (Analog to Digital) Converters are the key building blocks of wireless transceivers. In sigma delta modulator design,the scaling coefficients determine the peak signal-to-noise ratio. So selecting the optimum value of the coefficient is necessary. And therefore GA (Genetic Algorithm) is used for optimizing the coefficients. The performance of the design is analyzed ...

An audio band sigma-delta ADC based on a new time-interleaved !! scheme is described. The circuit achieves a very low power operation with the large dynamic range required for audio applications. This modified two channel timeinterleaved scheme improves the power efficiency thanks to halved operating frequency in the paths, and a reduced number of levels in ADC and DAC. This sigma-delta modulat...

This paper discusses a set of techniques for system-level simulation of continuous-time delta-sigma modulators (CT ∆∑M). In a top-down design flow, system-level simulation is an important part. Done accurately and correctly, system-level simulation can help predict when the circuit operates best and also when and where it fails. The building blocks in a CT ∆∑M and how the non-idealities with ea...