http://www.iaeme.com/IJECET/index.asp 13 editor@iaeme.com International Journal of Electronics and Communication Engineering and Technology (IJECET) Volume 7, Issue 4, July-August 2016, pp. 13–19, Article ID: IJECET_07_04_002 Available online at http://www.iaeme.com/IJECET/issues.asp?JType=IJECET&VType=7&IType=4 Journal Impact Factor (2016): 8.2691 (Calculated by GISI) www.jifactor.com ISSN Print: 0976-6464 and ISSN Online: 0976-6472 © IAEME Publication FIRST ORDER SIGMA DELTA MODULATOR USING 0.25 μM CMOS TECHNOLOGY AT 2.5 V Sonali Gandewar, Megha Soni and Vijay Sharma Swami Vivekanand College of Engineering, Indore, India ABSTRACT First order modulator is used in the sigma-delta modulator oversampled analog-to-digital (ADC) converter. Pseudo two phase latch based comparator with three stage cascading is used to get 2500 DC gain. Floating gate MOSFET is used at the input of integrator and comparator.ADC is implemented using 0.25 μm CMOS technology at 2.5 V. Index Terms: Analog-to-Digital Converter (ADC), Inverter, Sigma-Delta, nMOS, pMOS Cite this Article: Sonali Gandewar, Megha Soni and Vijay Sharma, First Order Sigma Delta Modulator Using 0.25 μM CMOS Technology at 2.5 V, International Journal of Electronics and Communication Engineering and Technology, 7(4), 2016, pp. 13–19. http://www.iaeme.com/IJECET/issues.asp?JType=IJECET&VType=7&IType=4 1. INTRODUCTION Over the years analog systems were dominating but the advantages digital signals made digital system designing more popular. Signals in general are analog in nature, so it becomes important to have systems that convert analog signals to digital signals to couple with digital systems. Every ADCs have their own advantages and disadvantages. Oversampled ADCs (sigma-delta) provides wide band frequency range from DC to several MHz with maximum accuracy [5]. Sigma delta ADC consists of oversampled modulator which is followed by decimation filter. Direct conversion of analog signal to digital signal is not possible. Figure 1 shows the general block diagram of a ADC which consist of prefilter, sample and hold, quantizer and encoder [6]