کنفرانس بین المللی میکروالکترونیک ایران

صفحه اصلی / پنجمین کنفرانس بین المللی میکروالکترونیک ایران

Design of 1-1-1 Cascaded Discrete-Time Delta-Sigma Modulator based on Tracking Quantizer

نویسندگان :

Mohsen Ghaemmaghami¹ Shahbaz Reyhani²

1- دانشگاه گیلان 2- دانشگاه گیلان

کلمات کلیدی :

Analog to digital converter،Digital to analog converter،Cascaded discrete-time delta-sigma modulator،Tracking quantizer

چکیده :

In this article, a multi-bit discrete-time delta-sigma modulator based on tracking quantizer for use in telecommunication applications is presented. The proposed 4-bit quantizer uses a comparator, an internal digital-to-analog converter (DAC) and a digital control circuit to predict the integrator output within one clock pulse. In addition, the use of one comparator in the proposed quantizer reduces the power and area consumption of the proposed modulator. In order to study the performance of the proposed method, a 1-1-1 cascaded multi-bit discrete-time delta-sigma with 4-bit proposed quantizer is designed and simulated at the transistor level in 180 nm CMOS technology. The simulation results show a signal-to-noise and distortion ratio (SNDR) of 72.9 dB in a bandwidth of 500 kHz. The oversampling ratio (OSR), power supply voltage and power consumption of the proposed modulator are 32, 1.8 V and 3.3 mW, respectively. In this design, the figure of merits (FoMs) are equal to 0.91 pJ/conv-step and 154.30 dB.