Design and Analysis of a 0.4V 1.08mW 12GHz High-Performance VCO in 0.18μm CMOS (Invited Paper)
To-Po Wang,
Chung-Chin Li
Issue:
Volume 1, Issue 5, December 2013
Pages:
107-113
Received:
30 October 2013
Published:
30 November 2013
Abstract: This paper presents the design and analysis of a high-performance fully-integrated 0.18μm CMOS voltage-controlled oscillator (VCO) with low supply voltage and low dc power consumption. To enhance the transconductance (gm) of MOSFETs and negative conductance (-Gm) of a cross-coupled pair, the device size of the nMOS cross-coupled pair is enlarged. For reducing the supply voltage and minimizing the dc power consumption, forward-body biased technique is utilized in this VCO, leading to the threshold voltage (Vt) reduction. Moreover, process variations are taken into accounted at low supply voltage, and the Monte-Carlo analysis is used to analyze the VCO phase noise and output power. At 0.4V low supply voltage, the fabricated 0.18μm CMOS VCO consumes 1.08mW low core power. At this bias condition, the measured phase noise at 1MHz offset from 12.77GHz carrier is -110.2 dBc/Hz, and the measured tuning range is 5.75%. Compared to recently published 0.18μm X-band CMOS VCOs, this work demonstrates the low supply voltage, low dc power dissipation, superior figure-of-merit (FOM), and better figure-of-merit including the tuning range (FOMT).
Abstract: This paper presents the design and analysis of a high-performance fully-integrated 0.18μm CMOS voltage-controlled oscillator (VCO) with low supply voltage and low dc power consumption. To enhance the transconductance (gm) of MOSFETs and negative conductance (-Gm) of a cross-coupled pair, the device size of the nMOS cross-coupled pair is enlarged. F...
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Analytical Surface Charge Control Model for AlN/GaN/AlGaN Double Heterojunction Field-Effect Transistor
Issue:
Volume 1, Issue 5, December 2013
Pages:
114-122
Received:
17 November 2013
Published:
30 November 2013
Abstract: We have argued that the nature of surface potential variation with gate voltage of AlN/GaN/AlGaN Double Heterojunction Field Effect Transistor (DHFET) is no different from that of the conventional GaAs/AlGaAs HEMT devices. Necessary simulated band diagrams have been presented to justify our claim and we have also proposed a non-linear expression for Fermi level (EF) variation with the two-dimensional electron gas density (2DEG). We have showed that our proposed expression provides better agreement with the numerical solution than the previous approximations. Besides, expression of surface charge density (ns) variation with gate voltage (VG) obtained using our proposed model, shows better fit with the numerical simulation data in wide range of bias conditions.
Abstract: We have argued that the nature of surface potential variation with gate voltage of AlN/GaN/AlGaN Double Heterojunction Field Effect Transistor (DHFET) is no different from that of the conventional GaAs/AlGaAs HEMT devices. Necessary simulated band diagrams have been presented to justify our claim and we have also proposed a non-linear expression fo...
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