الفهرس 
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Abstract
The interest for ∆Σ modulation-based ADC has significantly increased in the last years. For this reason ∆Σ modulator is unlike other converters that need accurate building blocks to obtain high resolution. On the other hand, the number of applications with industrial interest has also grown. Today we can find ∆Σ modulators in a large verity of ADC interfaces, and electronic devices systems. The rapid growing market of portable electronic systems such as wireless communication devices increases the demand for developing low-voltage and low-power circuit techniques and building blocks. Reducing the power dissipation in integrated circuits is required to extend the battery lifetime as much as possible. Furthermore, the increasing complexity on a chip results in an increase of power density and consequently the demand for power reduction. This thesis aims to design a simple low power dissipated ∆Σ modulator at low supply voltage and acceptable SNDR (signal to noise and distortion ratio). A dynamic comparator is used for more reduction in the power consumption. Also a loop filter is created using a SR (switched resistor) technique to reduce power dissipation, noise, circuit complexity and integrated silicon area as compared to SC (switched capacitor). Moreover a SR based integration requires smaller silicon area compared to continuous time technique. Some of very simple ∆Σ modulators circuits are designed using SR integrators and simulated using HSPICE in 0.18 µm technology. The PSD of ∆Σ modulators is extracted from digital output data using MATLAB. A 3-bit flash ADC is designed to be used as multi-bit quantizer taking the advantage of its speed property. A priority encoder evolved in flash ADC is designed in analog domain using HSPICE using 0.18 µm CMOS technology and in digital domain using Mentor Graphics and Xillinx ISE tools. The encoder is synthesized using Spartan chip.