An integrated 0.38–6 GHz, 9–12 GHz fully differential fractional-N frequency synthesizer for multi-standard reconfigurable MIMO communication application

A wide-band fully differential fractional-N frequency synthesizer for multi-standard application is presented. The single fully differential LC–VCO with 28.5 % tuning rang and a set of dividers, quadrature self-mixer are designed to accomplish the multi-frequency bands with the frequency band from 0.38 to 6 GHz and from 9.0 to 12 GHz. It covers several wireless standards. A novel high isolation multiplexer is presented to achieve the frequency band selection. This chip was implemented with 65 nm CMOS technology and the maximum consumption is 20.05 mA from 1.2 V power supply. It occupies an active area of 1.5 mm². The measured typical phase noise of the frequency synthesizer is ?114.6 dBc/Hz from 1 MHz offset for 4.85 GHz output.     

Ultra low power frequency divider for 2.45 GHz ZigBee frequency synthesizer

An ultra low power CMOS frequency divider whose modulus can be varied from 481 to 496 is presented. It has been customized to be used in 2.45 GHz Integer-N PLL frequency synthesizers utilized in ZigBee standard. Its based on swallow divider that replaces the swallow counter by a simple digital circuit in order to reduce power consumption and design complexity. Also a low power and high speed divide-by-7/8 is presented. Post layout simulation results exhibit 420 μW power consumption for 4 bit frequency divider in 2.45 GHz ISM frequency band that proves 40 % reduction compared to same previous works. All of the circuits have been designed in 0.18 μm TSMC CMOS technology with a single 1.8 V DC voltage supply.     

An instant-switching ?–Σ fractional-N frequency synthesizer with adjustable duty cycles

A Phase-Locked Loop (PLL)-based frequency synthesizer (FS) with adjustable duty cycle is presented. By employing digital processing circuitry and the ??C?? fractional-N technique, the FS is capable of generating arbitrary frequencies in a wide frequency range, and capable of adjusting the clock duty cycles. In addition, the switching between different frequencies is instant except when a very fine frequency resolution is required. The adjustable duty cycle and instant switching are desired features in applications such as time-interleaved Analog-to-Digital-Converters (ADCs), switched-capacitor circuits, and DC?CDC converters. The design was fabricated using a 0.13???m CMOS process. This paper gives the theories, analysis, implementation, and measurement results of this FS.     

A 1.78–3.05?GHz fractional-N frequency synthesizer with power reduced multi-modulus divider

Nowadays, multi-band frequency synthesizers are very popular for their compatibility, which lowers the chip cost. In this article, a low power 2.4?GHz broadband fractional-N frequency synthesizer based on ???C?? modulation is presented. A novel power reduced multi-modulus divider based on 2/3 divider cells is presented. The ??mod?? signals are employed to dynamically control the current of the end-of-cycle logic blocks in 2/3 divider cells. When the end-of-cycle logic blocks have no contribution to the divider operation, they are turned off to save power. The saved power is more than 30% in the desired division ratio range. A dual-band voltage controlled oscillator with switched capacitor arrays is designed to cover a wide tuning range. Other circuits such as phase frequency detector, charge pump and loop filter are also integrated on the chip. The whole frequency synthesizer has been fabricated in Chartered 0.18???m RF CMOS process. Tested results show it covers the tuning range from 1.78 to 3.05?GHz, with phase noise smaller than ?85 dBc/Hz at 100?kHz offset, and smaller than ?115 dBc/Hz at 3?MHz offset. Its power consumption is only 9.2?mW under 1.8?V supply voltage, and the chip occupies an area of 1.2?mm?×?1.3?mm.     

A 1.41–1.72 GHz sigma-delta fractional-N frequency synthesizer with a PVT insensitive VCO and a new prescaler

A 1.41–1.72 GHz fractional-N phase-locked loop (PLL) frequency synthesizer with a PVT insensitive voltage-controlled oscillator (VCO) is presented. In this PLL, a VCO with process, voltage, and temperature (PVT) insensitive bias circuit, and a divided-by-7/8 prescaler with improved multi-phase frequency divider are adopted. A novel multi-stage noise shaping (MASH) sigma-delta modulator (SDM) is adopted here. A new combination of low-current-mismatch charge pump (CP) and a phase/frequency detector (PFD) is proposed in this paper. Using Hejian Technology CMOS 0.18 μm analog and digital mixed-mode process, a fractional-N PLL prototype circuit is designed, the VCO in the prototype circuit can operate at a central frequency of 1.55 GHz, and its phase noise is −121 dBc/Hz at 1.0 MHz, the variety of phase noise is depressed by about 1.4 dB with the help of PVT insensitive bias. Under a 1.8-V supply voltage, the phase noise of the PLL is −113 dBc/Hz at 1.0 MHz.     

一种8 Bit 10 GHz SiGe BiCMOS比较器

SiGe BiCMOS提供了性能极其优异的HBT（异质结晶体管）,其ft超过70 GHz,β〉120,高线性,低噪声,非常适合高频领域应用。本文基于SiGe BiCMOS工艺。提出了一种高性能全差分超高速比较器,它由宽带宽前置放大器、改进的主从式锁存器组成。采用3．3v单电压源,比较时钟超过10GHz,差模信号电压输入量程为0．8V,输出差模电压为0．4V,输入失调电压约2．5mV,用于8位两步闪烁式AID转换器。     

A 0.13μm CMOS △∑ fractional-N frequency synthesizer for WLAN transceivers

A fractional-N frequency synthesizer fabricated in a 0.13 μm CMOS technology is presented for the application of IEEE 802.11 b/g wireless local area network (WLAN) transceivers.A monolithic LC voltage controlled oscillator (VCO) is implemented with an on-chip symmetric inductor.The fractional-N frequency divider consists of a pulse swallow frequency divider and a 3rd-order multistage noise shaping (MASH) △ ∑ modulator with noise-shaped dithering techniques.Measurement results show that in all channels,phase noise of the synthesizer achieves -93 dBc/Hz and -118 dBc/Hz in band and out of band respectively with a phase-frequency detector (PFD) frequency of 20 MHz and a loop bandwidth of 100 kHz.The integrated RMS phase error is no more than 0.8°.The proposed synthesizer consumes 8.4 mW from a 1.2 V supply and occupies an area of 0.86 mm2.     

A 0.13μm CMOS Δ ∑ fractional-N frequency synthesizer for WLAN transceivers

A fractional-N frequency synthesizer fabricated in a 0.13μm CMOS technology is presented for the application of IEEE 802.11 b/g wireless local area network(WLAN) transceivers.A monolithic LC voltage controlled oscillator(VCO) is implemented with an on-chip symmetric inductor.The fractional-TV frequency divider consists of a pulse swallow frequency divider and a 3rd-order multistage noise shaping(MASH)△Σmodulator with noise-shaped dithering techniques.Measurement results show that in all channels,phase noise of the synthesizer achieves -93 dBc/Hz and -118 dBc/Hz in band and out of band respectively with a phase-frequency detector (PFD) frequency of 20 MHz and a loop bandwidth of 100 kHz.The integrated RMS phase error is no more than 0.8°.The proposed synthesizer consumes 8.4 mW from a 1.2 V supply and occupies an area of 0.86 mm~2.     

A 55 nm CMOS △∑fractional-N frequency synthesizer for WLAN transceivers with low noise filters

A fully integrated ΔΣ fractional-N frequency synthesizer fabricated in a 55 nm CMOS technology is presented for the application of IEEE 802.11b/g wireless local area network(WLAN) transceivers.A low noise filter,occupying a small die area,whose power supply is given by a high PSRR and low noise LDO regulator,is integrated on chip.The proposed synthesizer needs no off-chip components and occupies an area of 0.72 mm2 excluding PAD.Measurement results show that in all channels,the phase noise of the synthesizer achieves -99 dBc/Hz and -119 dBc/Hz in band and out of band respectively with a reference frequency of 40 MHz and a loop bandwidth of 200 kHz.The integrated RMS phase error is no more than 0.6°.The proposed synthesizer consumes a total power of 15.6 mW.     

A 0.9–5.4 GHz wideband fast settling frequency synthesizer for 5G based consumer services

In this paper, a frequency synthesizer, based on a type-2, third order phase locked loop (PLL), covering the frequency range of 0.9–5.4 GHz using three voltage controlled oscillators, is implemented using a 0.13-\(\upmu \hbox {m}\) CMOS technology. The PLL has three modes of operation—a high bandwidth mode, a low bandwidth mode and a dynamic mode, in which the bandwidth dynamically changes from a low to a high value, during a frequency jump, and reverts back to low value, once the PLL settles. With a proper choice of bandwidth and timing synchronization during a frequency jump, a worst-case settling time of 3-\(\upmu \hbox {s}\) has been obtained, which is one of the lowest in reported literature. The input clock of the PLL is set to 100 MHz, but it can go as low as 25 MHz without having any effect on its settling time. The PLL consumes 24 mW of power and occupies 0.8 mm\(^2\) of active area.This PLL is expected to be specially useful in wide-bandwidth cognitive radios that require large and fast transitions in the frequency of operation.     

A 2.4 GHz power amplifier in 0.35 μm SiGe BiCMOS

This paper presents a 2.4 GHz power amplifier (PA) designed and implemented in 0.35 μm SiGe BiCMOS technology. Instead of chip grounding through PCB vias, a metal plate with a mesa connecting ground is designed to decrease the parasitics in the PCB, improving the stability and the gain of the circuit. In addition, a low-pass network for output matching is designed to improve the linearity and power capability. At 2.4 GHz, a P_(1dB) of 15.7 dBm has been measured, and the small signal gain is 27.6 dB with S_(11) < -7 dB and S_(22) < -15 dB.     

A 2.4 GHz power amplifier in 0.35μm SiGe BiCMOS

This paper presents a 2.4 GHz power amplifier(PA) designed and implemented in 0.35μm SiGe BiCMOS technology.Instead of chip grounding through PCB vias,a metal plate with a mesa connecting ground is designed to decrease the parasitics in the PCB,improving the stability and the gain of the circuit.In addition,a low-pass network for output matching is designed to improve the linearity and power capability.At 2.4 GHz,a P_(1dB) of 15.7 dBm has been measured,and the small signal gain is 27.6 dB with S_(11)<-7 ...     

79 GHz fully integrated fully differential Si/SiGe HBT amplifier for automotive radar applications

In this work, a fully integrated, fully differential amplifier operating at 79 GHz using a high-speed Si/SiGe heterojunction bipolar technology is presented. This integrated circuit needs a single supply voltage and shows high performance such as high gain, excellent reverse isolation and low power consumption (90 mW at 3 V supply voltage). This result was achieved by using three cascaded cascode amplifiers as well as thin-film microstrip lines and MIM capacitors as reactive elements. In addition, the frequency of operation can be easily adjusted within a wide range by changing the length of the matching network (by using a focused ion beam or an ultrasonic manipulator). Because the measurement of differential ICs operating in the millimeter-wave domain is complex, a simple but efficient layout modification was utilized to easily measure single-ended the differential integrated circuit, also at these high frequencies.     

A △∑ fractional-N frequency synthesizer for FM tuner using low noise filter and quantization noise suppression technique

A △∑ fractional-N frequency synthesizer fabricated in a 130 nm CMOS technology is presented for the application of an FM tuner. A low noise filter, occupying a small die area and decreasing the output noise, is integrated on a chip. A quantization noise suppression technique, using a reduced step size of the frequency divider, is also adopted. The proposed synthesizer needs no off-chip components and occupies an area of 0.7 mm2. The in-band phase noise （from 10 to 100 kHz） below -108 dBc/Hz and out-of-band phase noise of -122.9 dBc/Hz （at 1 MHz offset） are measured with a loop bandwidth of 200 kHz. The quantization noise suppression technique reduces the in-band and out-of band phase noise by 15 dB and 7 dB respectively. The integrated RMS phase error is no more than 0.48°. The proposed synthesizer consumes a total power of 7.4 mW and the frequency resolution is less than 1 Hz.     

A highly linear and fully-integrated FMCW synthesizer for 60 GHz radar applications with 7 GHz bandwidth

A highly linear and fully-integrated frequency-modulated continuous-wave (FMCW) generator based on a fractional-N phase-locked loop (PLL) that is able to synthesize modulation schemes in 57–64 GHz range is proposed in this paper. The fractional-N PLL employs Colpitts voltage-controlled oscillator (VCO) at 60 GHz with 13.5% tuning range. Automatic amplitude and frequency calibrations are implemented to avoid drifts due to process, voltage and temperature variations and to set the center frequency of the VCO. Five-stage multi-modulus divider is used for division ratio switching, controlled by the sigma-delta (\(\Sigma \Delta\)) modulator MASH 1-1-1. The frequency sweep (chirp) bandwidth and duration are fully programmable via serial peripheral interface allowing up to 16 different chirps in complex modulation scheme. The PLL reference signal is 250 MHz provided by external low-noise signal generator which is also used for digital modules clock. The overall PLL phase noise is lower than ?80 dBc/Hz at 10 kHz offset and the chirp linearity is better than 0.01%. The complete FMCW synthesizer is implemented and verified as a stand-alone chip in a commercially available SiGe HBT 130 nm BiCMOS technology. The total chip area is \(2.04\,\text {mm}^2\), and the total power consumption is 280 mW.     

An ultra-wide-band 3.1-10.6 GHz LNA design in 0.18 μm SiGe BiCMOS

A two-stage monolithic ultra-wide-band (UWB) low-noise-amplifier (LNA) designed for MB-OFDM in 0.18 μm SiGe BiCMOS process is presented. With an optimized configuration combining advantages of RES-feedback and LC-ladder matching structure, the adjustable wide input matching is got and noise figure (NF) is controlled to a relevant low status. The measured S21 is from 7.6 to 14.2 dB over the 3-11 GHz operating band, NF is from 3.2 dB to 4.8 dB. With a 2.5 V power supply, the LNA has an overall power consumption of 14.5 mW.     

E-Band Active Q-Enhanced Pseudo-combline Resonator in 130 nm SiGe BiCMOS

We present an active Q-enhanced pseudo-combline resonator integrated in 130 nm SiGe BiCMOS. It is shown that the resonator Q₀ can be enhanced, controllably, from 15 to 1578 at 78.8 GHz through application of a SiGe HBT-based negative resistance circuit. This is the first time that resonator Q-enhancement is demonstrated experimentally in silicon above 40 GHz, and the first time negative enhancement with single-ended pseudo-combline loading is used.