IJMTES – DESIGN OF A DOUBLE TAIL DYNAMIC COMPARATOR FOR LOW POWER AND HIGH SPEED APPLICATIONS

Journal Title : International Journal of Modern Trends in Engineering and Science

Author’s Name : C Manoj Kumar | C.Bruhathi Reddy unnamed

Volume 03 Issue 08 2016

ISSN no:  2348-3121

Page no: 35-39

Abstract – Now a days the entire world is running towards digitalization process in every field as digitalization is rapidly becoming one of the standard form of processing, storage and transmission of information. Digitalization is nothing but the conversion of traditional analog data into digital format.in that scenario we necessitate a converter to change the analog data .so, in essential we go for ADC’s. The want of analog to digital converters with very-low power, area efficient and excessive speed is giving more chance to the use of dynamic regenerative comparators to increase the speed and power efficiency. Clocked comparators are regularly referred to as dynamic comparators. Dynamic double tail comparators are compared in terms of their power, speed and delay. The accuracy of comparators that is defined by using its electricity intake and speed is of eager interest in attaining over all better performance of ADCs. In the domain of signal processing with low power VLSI, the function of ADC device is crucial.Many high speed ADCs, such as flash ADCs, require excessive speed, low power comparators with small chip area. Compared with the double tail comparator in the proposed comparator both the power consumption and delay time are substantially reduced. Design has particularly focused on delay of double-tail comparator, which are called clocked regenerative comparator. In this paper, an analysis on the delay of the dynamic comparators will be presented and analytical expressions are derived. From the analytical expressions, designers can obtain an intuition about the primary contributors to the comparator delay and fully explore the tradeoffs in dynamic comparator layout. Based on the existing analysis, a new dynamic comparator is proposed, where the circuit of traditional double tail dynamic comparator is altered for low power and fast operation even in small supply voltages. Here by adding a few transistors, the power consumptions can be reduced drastically. Post–layout simulation using 90nm CMOS technology confirms the analysis results of the proposed dynamic comparator.

Keywords— Analog to digital comparators, Clocked comparators, Dynamic double tail comparator, Flash ADC, Dynamic comparator 

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