Circuits and Systems II: Express Briefs, …, Jan 1, 2012
Here, we investigate the design of a Ku-band Armstrong voltage-controlled oscillator (VCO) utiliz... more Here, we investigate the design of a Ku-band Armstrong voltage-controlled oscillator (VCO) utilizing dual transformer feedback for low-voltage low-power operation. The primary transformer feedback between the drain and the source of the VCO increases the output voltage swing under low supply voltage. With the secondary transformer feedback, g_m-boosting is obtained by the coupling between the drain and the gate of the Armstrong VCO. Combined with transformer feedback, g_m-boosting further reduces the negative transconductance required for oscillation startup, enabling ultralow-power operation. Thus, the proposed Armstrong VCO with dual feedback operates at 0.4 V with power consumption as low as 600 W. Under this condition, the measured phase noise of the VCO is -100.6 dB/Hz at 1-MHz offset from a 14.1-GHz carrier. The results show that the proposed VCO is suitable for very low-power applications requiring high signal purity.
In this paper, we present a novel low power voltage-controlled-oscillator (VCO) based on bandwidt... more In this paper, we present a novel low power voltage-controlled-oscillator (VCO) based on bandwidth enhancement technique. The enhanced bandwidth allowed the VCO to achieve steep output waveform resulting in improved phase noise. The VCO was fabricated in 0.13 μm standard CMOS process having 6 layers of copper metallization. The oscillation frequency ranged from 4.48 to 4.82 GHz with a turning range of 7.5%. The measured phase noise of the VCO was -119 dBc/Hz at 1 MHz offset under 4.2 mW power consumption.
This paper presents millimeter-wave CMOS building blocks for a high date rate wireless transceive... more This paper presents millimeter-wave CMOS building blocks for a high date rate wireless transceiver. The results include measured data for a 40-50 GHz broad-band low noise amplifier, a 40 GHz tuned power amplifier, and an 18 GHz voltage controlled oscillator. Also, simulation results for a 22 GHz multi-modulus prescaler is presented for implementing phase locked loop. The circuits were fabricated 0.13 ¿m CMOS process. The measured results showed good agreement with simulation data demonstrating good modeling accuracy of CMOS active and passive devices for millimeter-wave applications.
In this letter, we present the measured performance of a differential Vackar voltage-controlled o... more In this letter, we present the measured performance of a differential Vackar voltage-controlled oscillator (VCO) implemented for the first time in CMOS technology. The Vackar VCO provided good isolation between the LC tank and the loss-compensating active circuit; thus, excellent frequency stability was achieved over the frequency tuning range. The Vackar VCO was implemented using nMOS transistors and an LC tank in a 0.18 μm RF CMOS process. The oscillation frequency ranged from 4.85 to 4.93 GHz. The measured phase noise of the Vackar VCO at 1 MHz offset was -124.9 dB/Hz at 4.9 GHz with a figure-of-merit (FOM) of -188 dBc/Hz.
Circuits and Systems II: Express Briefs, …, Jan 1, 2012
Here, we investigate the design of a Ku-band Armstrong voltage-controlled oscillator (VCO) utiliz... more Here, we investigate the design of a Ku-band Armstrong voltage-controlled oscillator (VCO) utilizing dual transformer feedback for low-voltage low-power operation. The primary transformer feedback between the drain and the source of the VCO increases the output voltage swing under low supply voltage. With the secondary transformer feedback, g_m-boosting is obtained by the coupling between the drain and the gate of the Armstrong VCO. Combined with transformer feedback, g_m-boosting further reduces the negative transconductance required for oscillation startup, enabling ultralow-power operation. Thus, the proposed Armstrong VCO with dual feedback operates at 0.4 V with power consumption as low as 600 W. Under this condition, the measured phase noise of the VCO is -100.6 dB/Hz at 1-MHz offset from a 14.1-GHz carrier. The results show that the proposed VCO is suitable for very low-power applications requiring high signal purity.
In this paper, we present a novel low power voltage-controlled-oscillator (VCO) based on bandwidt... more In this paper, we present a novel low power voltage-controlled-oscillator (VCO) based on bandwidth enhancement technique. The enhanced bandwidth allowed the VCO to achieve steep output waveform resulting in improved phase noise. The VCO was fabricated in 0.13 μm standard CMOS process having 6 layers of copper metallization. The oscillation frequency ranged from 4.48 to 4.82 GHz with a turning range of 7.5%. The measured phase noise of the VCO was -119 dBc/Hz at 1 MHz offset under 4.2 mW power consumption.
This paper presents millimeter-wave CMOS building blocks for a high date rate wireless transceive... more This paper presents millimeter-wave CMOS building blocks for a high date rate wireless transceiver. The results include measured data for a 40-50 GHz broad-band low noise amplifier, a 40 GHz tuned power amplifier, and an 18 GHz voltage controlled oscillator. Also, simulation results for a 22 GHz multi-modulus prescaler is presented for implementing phase locked loop. The circuits were fabricated 0.13 ¿m CMOS process. The measured results showed good agreement with simulation data demonstrating good modeling accuracy of CMOS active and passive devices for millimeter-wave applications.
In this letter, we present the measured performance of a differential Vackar voltage-controlled o... more In this letter, we present the measured performance of a differential Vackar voltage-controlled oscillator (VCO) implemented for the first time in CMOS technology. The Vackar VCO provided good isolation between the LC tank and the loss-compensating active circuit; thus, excellent frequency stability was achieved over the frequency tuning range. The Vackar VCO was implemented using nMOS transistors and an LC tank in a 0.18 μm RF CMOS process. The oscillation frequency ranged from 4.85 to 4.93 GHz. The measured phase noise of the Vackar VCO at 1 MHz offset was -124.9 dB/Hz at 4.9 GHz with a figure-of-merit (FOM) of -188 dBc/Hz.
Uploads
Papers by Tai N. Nguyen