A 3.6-GHz digital fractional-N frequency synthesizer achieving low noise and 500-kHz bandwidth is presented. This architecture uses a gated-ring-oscillator time-to-digital converter (TDC) with 6-ps raw resolution and first-order shaping of its quantization noise along with digital quantization noise cancellation to achieve integrated phase noise of less than 300 fs (1 kHz to 40 MHz). The synthesizer includes two 10-bit 50-MHz passive digital-to-analog converters for digital control of the oscillator and an asynchronous frequency divider that avoids divide-value delay variation at its output. Implemented in a 0.13-mum CMOS process, the prototype occupies 0.95-mm2 active area and dissipates 39 mW for the core parts with another 8 mW for the oscillator output buffer. Measured phase noise at 3.67 GHz carrier frequency is -108 and -150 dBc/Hz at 400 kHz and 20 MHz offset, respectively.

A Low-Noise Wide-BW 3.6-GHz Digital $\Delta\Sigma$ Fractional-N Frequency Synthesizer With a Noise-Shaping Time-to-Digital Converter and Quantization Noise Cancellation

A fully integrated, programmable mixed-signal transceiver comprising a radio frequency integrated circuit (RFIC) which is frequency and protocol agnostic with digital inputs and outputs, the transceiver being programmable and configurable for multiple radio frequency bands and standards and being capable of connecting to many networks and service providers. The RFIC does not use spiral inductors and instead includes transmission line inductors allowing for improved scalability. Components of the transceiver are programmable to allow the transceiver to switch between different frequency bands of operating. Frequency switching can be accomplished though the content of digital registers coupled to the components.

Programmable radio transceiver

Radio frequency integrated circuits (RFICs) are the building blocks that enable every device from cable television sets to mobile telephones to transmit and receive signals and data. This newly revised and expanded edition of the 2003 Artech House classic, "Radio Frequency Integrated Circuit Design", serves as an up-to-date, practical reference for complete RFIC know-how. The second edition includes numerous updates, including greater coverage of CMOS PA design, RFIC design with on-chip components, and more worked examples with simulation results. By emphasizing working designs, this book practically transports readers into the authors' own RFIC lab so they can fully understand how these designs function. This title is suitable for radio frequency integrated circuit (RFIC) design engineers; radio systems architects; researchers and developers of RFIC technology; and, graduate level electrical engineering students.

Radio Frequency Integrated Circuit Design

A digital fractional-N frequency synthesizer is presented that leverages a noise-shaping time-to-digital converter (TDC) and a simple quantization noise cancellation technique to achieve low phase noise with a wide PLL bandwidth of 500kHz. In contrast to previous cancellation techniques, this structure requires no analog components and is straightforward to implement with standard-cell digital logic.

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A Low-Noise, Wide-BW 3.6GHz Digital ΔΣ Fractional-N Frequency Synthesizer with a Noise-Shaping Time-to-Digital Converter and Quantization Noise Cancellation

The design of a 2.4-GHz fully integrated /spl Sigma//spl Delta/ fractional-N frequency synthesizer in a 0.35-/spl mu/m CMOS process is presented. The design focuses on the prescaler and the loop filter, which are often the speed and the integration bottlenecks of the phase-locked loop (PLL), respectively. A 1.5-V 3-mW inherently glitch-free phase-switching prescaler is proposed. It is based on eight lower frequency 45/spl deg/-spaced phases and a reversed phase-switching sequence. The large integrating capacitor in the loop filter was integrated on chip via a simple capacitance multiplier that saves silicon area, consumes only 0.2 mW, and introduces negligible noise. The synthesizer has a 9.4% frequency tuning range from 2.23 to 2.45 GHz. It dissipates 16 mW and takes an active area of 0.35 mm/sup 2/ excluding the 0.5-mm/sup 2/ digital /spl Sigma//spl Delta/ modulator.

A 2.4-GHz monolithic fractional-N frequency synthesizer with robust phase-switching prescaler and loop capacitance multiplier

A truly modular and power-scalable architecture for low-power programmable frequency dividers is presented. The architecture was used in the realization of a family of low-power fully programmable divider circuits, which consists of a 17-bit UHF divider, an 18-bit L-band divider, and a 12-bit reference divider. Key circuits of the architecture are 2/3 divider cells, which share the same logic and the same circuit implementation. The current consumption of each cell can be determined with a simple power optimization procedure. The implementation of the 2/3 divider cells is presented, the power optimization procedure is described, and the input amplifiers are briefly discussed. The circuits were processed in a standard 0.35 /spl mu/m bulk CMOS technology, and work with a nominal supply voltage of 2.2 V. The power efficiency of the UHF divider is 0.77 GHz/mW, and of the L-band divider, 0.57 GHz/mW. The measured input sensitivity is >10 mV rms for the UHF divider, and >20 mV rms for the L-band divider.

M. Locher

Papers

A family of low-power truly modular programmable dividers in standard 0.35-/spl mu/m CMOS technology