A wideband sigma-delta phase-locked-loop modulator for wireless applications

Author(s):  
A.M. Fahim ◽  
M.I. Elmasry
Author(s):  
P.N. Metange ◽  
K. B. Khanchandani

<p>This paper presents the analysis and design of high performance phase frequency detector, charge pump and loop filter circuits for phase locked loop in wireless applications. The proposed phase frequency detector (PFD) consumes only 8 µW and utilises small area. Also, at 1.8V voltage supply the maximum operation frequency of the conventional PFD is 500 MHz whereas proposed PFD is 5 GHz. Hence, highly suitable for low power, high speed and low jitter applications.  The differential charge pump uses switches using NMOS and the inverter delays for up and down signals do not generate any offset due to its fully symmetric operation. This configuration doubles the range of output voltage compliance compared to single ended charge pump. Differential stage is less sensitive to the leakage current since leakage current behaves as common mode offset with the dual output stages. All the circuits are implemented using cadence 0.18 μm CMOS Process.</p>


2012 ◽  
Vol 21 (04) ◽  
pp. 1250028 ◽  
Author(s):  
B. HODA SEYEDHOSSEINZADEH ◽  
MOHAMMAD YAVARI

This paper describes the design and implementation of a reconfigurable low-power sigma-delta modulator (SDM) for multi-standard wireless communications in a 90 nm CMOS technology. Both architectural and circuital reconfigurations are used to adapt the performance of the modulator to multi-standard applications. The feasibility of the presented solution is demonstrated using system-level simulations as well as transistor-level simulations of the modulator. HSPICE simulation results show that the proposed modulator achieves 76.8/78.9/80.8/85/89.5 dB peak signal-to-noise plus distortion ratio (SNDR) within the standards WiFi, WiMAX, WCDMA, Bluetooth and GSM with the bandwidth of 12.5 MHz, 10 MHz, 1.92 MHz, 0.5 MHz, and 250 kHz, respectively, under the power consumption of 37/37/12/5/5 mW using a single 1 V power supply.


Sign in / Sign up

Export Citation Format

Share Document