A 1.8-V 10-Gb/s fully integrated CMOS optical receiver analog front-end

A fully integrated 10-Gb/s optical receiver analog front-end (AFE) design that includes a transimpedance amplifier (TIA) and a limiting amplifier (LA) is demonstrated to require less chip area and is suitable for both low-cost and low-voltage applications. The AFE is fabricated using a 0.18-/spl mu/m CMOS technology. The tiny photo current received by the receiver AFE is amplified to a differential voltage swing of 400 mV/sub (pp)/. In order to avoid off-chip noise interference, the TIA and LA are dc-coupled on the chip instead of ac-coupled though a large external capacitor. The receiver front-end provides a conversion gain of up to 87 dB/spl Omega/ and -3dB bandwidth of 7.6 GHz. The measured sensitivity of the optical receiver is -12dBm at a bit-error rate of 10/sup -12/ with a 2/sup 31/-1 pseudorandom test pattern. Three-dimensional symmetric transformers are utilized in the AFE design for bandwidth enhancement. Operating under a 1.8-V supply, the power dissipation is 210 mW, and the chip size is 1028 /spl mu/m/spl times/1796 /spl mu/m.     

A 2.4-GHz sub-mW CMOS receiver front-end for wireless sensors network

A 2.4-GHz fully integrated CMOS receiver front-end using current-reused folded-cascode circuit scheme is presented. A configuration utilizing vertically stacked low-noise amplifier (LNA) and a folded-cascode mixer is proposed to improve both conversion gain and noise figure suitable for sub-mW receiver circuits. The proposed front-end achieves a conversion gain of 31.5dB and a noise figure of 11.8dB at 10MHz with 500-/spl mu/A bias current from a 1.0-V power supply. The conversion gain and noise figure improvements of the proposed front-end over a conventional merged LNA and single-balanced mixer are 11dB and 7.2dB at 10MHz, respectively, with the same power consumption of 500/spl mu/W.     

Micro-power low-offset instrumentation amplifier IC design for biomedical system applications

This work presents a micro-power low-offset CMOS instrumentation amplifier integrated circuit with a large operating range for biomedical system applications. The equivalent input offset voltage is improved using a new circuit technique of offset cancellation that involves a two-phase clocking scheme with a frequency of 20 kHz. Channel charge injection is cancelled by the symmetrical circuit topology. With the wide-swing cascode bias circuit design, this amplifier realizes a very high power-supply rejection ratio (PSRR), and can be operated at single supply voltage in the range between 2.5-7.5 V. It was fabricated using 0.5-/spl mu/m double-poly double-metal n-well CMOS technology, and occupies a die area of 0.2 mm/sup 2/. This amplifier achieves a 160-/spl mu/V typical input offset voltage, 0.05% gain linearity, greater than 102-dB PSRR, an input-referred rms noise voltage of 45 /spl mu/V, and a current consumption of 61 /spl mu/A at a low supply voltage of 2.5 V. Experimental results indicate that the proposed amplifier can process the input electrocardiogram signal of a patient monitoring system and other portable biomedical devices.     

A 0.13 /spl mu/m CMOS front-end, for DCS1800/UMTS/802.11b-g with multiband positive feedback low-noise amplifier

This paper presents a fully integrated CMOS receiver front-end based on a direct conversion architecture for UMTS/802.11b-g and a low-IF architecture at 100 kHz for DCS1800. The two key building blocks are a multiband low-noise amplifier (LNA) that uses positive feedback to improve its gain and a highly linear mixer. The front-end, integrated in a 0.13 /spl mu/m CMOS process, exhibits a minimum noise figure of 5.2 dB, a programmable gain that can be varied from 13.5 to 28.5 dB, an IIP3 of more than -7.5 dBm and an IIP2 better than 50 dBm. The total current consumption is 20mA from a 1.2V supply.     

Design of a low-power 3.5-GHz broad-band CMOS transimpedance amplifier for optical transceivers

This paper describes a novel low-power low-noise CMOS voltage-current feedback transimpedance amplifier design using a low-cost Agilent 0.5-/spl mu/m 3M1P CMOS process technology. Theoretical foundations for this transimpedance amplifier by way of gain, bandwidth and noise analysis are developed. The bandwidth of the amplifier was extended using the inductive peaking technique, and, simulation results indicated a -3-dB bandwidth of 3.5 GHz with a transimpedance gain of /spl ap/60 dBohms. The dynamic range of the amplifier was wide enough to enable an output peak-to-peak voltage swing of around 400 mV for a test input current swing of 100 /spl mu/A. The output noise voltage spectral density was 12 nV//spl radic/Hz (with a peak of /spl ap/25 nV//spl radic/Hz), while the input-referred noise current spectral density was below 20 pA//spl radic/Hz within the amplifier frequency band. The amplifier consumes only around 5 mA from a 3.3-V power supply. A test chip implementing the transimpedance amplifier was also fabricated using the low-cost CMOS process.     

Low-power fully integrated and tunable CMOS RF wireless receiver for ISM band consumer applications

A 0.25-/spl mu/m single-chip CMOS single-conversion tunable low intermediate frequency (IF) receiver operated in the 902-928-MHz industrial, scientific, and medical band is proposed. A new 10.7-MHz IF section that contains a limiting amplifier and a frequency modulated/frequency-shift-key demodulator is designed. The frequency to voltage conversion gain of the demodulator is 15 mV/kHz and the dynamic range of the limiting amplifier is around 80 dB. The sensitivity of the IF section including the demodulator and limiting amplifier is -72 dBm. With on-chip tunable components in the low-power low-noise amplifier (LNA) and LC-tank voltage-controlled oscillator circuit, the receiver measures an RF gain of 15 dB at 915 MHz, a sensitivity of -80 dBm at 0.1% bit-error rate, an input referred third-order intercept point of -9 dBm, and a noise figure of 5 dB with a current consumption of 33 mA and a 2450 /spl mu/m/spl times/ 2450 /spl mu/m chip area.     

An integrated low power highly linear 2.4-GHz CMOS receiver front-end based on current amplification and mixing

A low power 2.4-GHz complementary metal oxide semiconductor (CMOS) receiver front-end using highly linear mixer based on current amplification and mixing is reported. In the proposed mixer, linearity is greatly improved by using current mirror amplifier and transconductance linearization using multiple gated transistors. Single IF direct conversion receiver (DCR) architecture is used to achieve higher level of integration and to relax the problem of DCR. The fully integrated receiver front end is fabricated in 0.18-/spl mu/m CMOS technology and HP3 of -9 dBm with a gain of 32 dB and noise figure of 6.5 dB are obtained at 8.8 mW power consumption.     

A 1.2 mW RDS receiver for portable applications

A 0.9 V 1.2 mA fully integrated radio data system (RDS) receiver for the 88-108 MHz FM broadcasting band is presented. Requiring only a few external components (matching network, VCO inductors, loop filter components), the receiver, which has been integrated in a standard digital 0.18 /spl mu/m CMOS technology, achieves a noise figure of 5 dB and a sensitivity of -86dBm. The circuit can be configured and the RDS data retrieved via an I/sup 2/C interface so that it can very simply be used as a peripheral in any portable application. A 250 kHz low-IF architecture has been devised to minimize the power dissipation of the baseband filters and FM demodulator. The frequency synthesizer consumes 250 /spl mu/A, the RF front-end 450 /spl mu/A while providing 40 dB of gain, the baseband filter and limiters 100 /spl mu/A, and the FM and BPSK analog demodulators 300 /spl mu/A. The chip area is 3.6 mm/sup 2/.     

A CMOS ultra-wideband impulse radio transceiver for 1-mb/s data communications and /spl plusmn/2.5-cm range finding

A CMOS ultra-wideband impulse radio (UWB-IR) transceiver was developed in 0.18-/spl mu/m CMOS technology. It can be used for 1-Mb/s data communications as well as for precise range finding within an error of /spl plusmn/2.5 cm. The power consumptions of the transmitter and receiver for data communication are 0.7 and 4.0 mW, respectively. When an LNA operates intermittently through bias switching, the power consumption of the transceiver is only 1 mW. The range for data communication is 1 m with BER of 10/sup -3/. For ranging applications, the transmitter can reduce the power to 0.7 /spl mu/W for 1k pulses per second, and the receiver consumes little power. The transceiver design, all-digital transmitter, and intermittent circuit operation at the receiver reduce the power consumption dramatically, which makes the transceiver well suited for applications like sensor networks. The electronic field intensity is lower than 35 /spl mu/V/m, and thus the UWB system can be operated even under the current Japan radio regulations.     

A CMOS chopper amplifier

A highly sensitive CMOS chopper amplifier for low-frequency applications is described. It is realized with a second-order low-pass selective amplifier using a continuous-time filtering technique. The circuit has been integrated in a 3-/spl mu/m p-well CMOS technology. The chopper amplifier DC grain is 38 dB with a 200-Hz bandwidth. The equivalent input noise is 63 nV//spl radic/Hz and free from 1/f noise. The input offset is below 5 /spl mu/V for a tuning error less than 1%. The amplifier consumes only 34 /spl mu/W.     

A CMOS analog front-end IC for portable EEG/ECG monitoring applications

A new digital programmable CMOS analog front-end (AFE) IC for measuring electroencephalograph or electrocardiogram signals in a portable instrumentation design approach is presented. This includes a new high-performance rail-to-rail instrumentation amplifier (IA) dedicated to the low-power AFE IC. The measurement results have shown that the proposed biomedical AFE IC, with a die size of 4.81 mm/sup 2/, achieves a maximum stable ac gain of 10 000 V/V, input-referred noise of 0.86 /spl mu/ V/sub rms/ (0.3 Hz-150 Hz), common-mode rejection ratio of at least 115 dB (0-1 kHz), input-referred dc offset of less than 60 /spl mu/V, input common mode range from -1.5 V to 1.3 V, and current drain of 485 /spl mu/A (excluding the power dissipation of external clock oscillator) at a /spl plusmn/1.5-V supply using a standard 0.5-/spl mu/m CMOS process technology.     

Wideband fully differential CMOS transimpedance preamplifier

A fully differential transimpedance amplifier has been designed and implemented in 0.18 /spl mu/m standard digital CMOS technology. The parallel feedback circuit topology is adopted to broaden the bandwidth. It can operate at 10 Gbit/s with the dynamic range from 25 /spl mu/A up to 2.5 mA. The power consumption is only 88 mW under 2 V supply voltage.     

A 72-mW CMOS 802.11a direct conversion front-end with 3.5-dB NF and 200-kHz 1/f noise corner

A direct conversion 802.11a receiver front-end including a synthesizer with quadrature VCO has been integrated in a 0.13-/spl mu/m CMOS process. The chip has an active area of 1.8 mm/sup 2/ with the entire RF portion operated from 1.2 V and the low frequency portion operated from 2.5 V. Its key features are a current driven passive mixer with a low impedance load that achieves a low 1/f noise corner and an high I-Q accuracy quadrature VCO. Measured noise figure is 3.5 dB with an 1/f noise corner of 200 kHz, and an IIP3 of -2 dBm. The synthesizer DSB phase noise integrated over a 10 MHz band is less than -36 dBc while its I-Q phase unbalance is below 1 degree.     

基于0.18μm CMOS工艺2.5Gb/s宽动态范围光接收机前端放大电路设计

基于0.18μm CMOS工艺设计了适用于2.5Gb/s传输速率的宽动态范围光接收机前端放大电路（包括前置放大器和限幅放大器）.前置放大器采用了RGC输入级的跨阻放大器,并且应用了消直流电路和自动增益控制电路扩展输入动态范围.限幅放大器采用了按比例缩小尺寸、并联峰化和带有有源负反馈的Cherry-Hooper放大器等方法扩展带宽.仿真结果表明：前端放大电路的中频增益为116dBΩ,-3dB带宽为2.13GHz,输入信号动态范围为40dB（0.01～1mA）.     

1-Gb/s 80-dB/spl Omega/ fully differential CMOS transimpedance amplifier in multichip on oxide technology for optical interconnects

A 1-Gb/s differential transimpedance amplifier (TIA) is realized in a 0.25-/spl mu/m standard CMOS technology, incorporating the regulated cascode input configuration. The TIA chip is then integrated with a p-i-n photodiode on an oxidized phosphorous-silicon (OPS) substrate by employing the multichip-on-oxide (MCO) technology. The MCO TIA demonstrates 80-dB/spl Omega/ transimpedance gain, 670-MHz bandwidth for 1-pF photodiode capacitance, 0.54-/spl mu/A average input noise current, -17-dBm sensitivity for 10/sup -12/ bit-error rate (BER), and 27-mW power dissipation from a single 2.5-V supply. It also shows negligible switching noise effect from an embedded VCO on the OPS substrate. Furthermore, a four-channel MCO TIA array is implemented for optical interconnects, resulting in less than -40-dB crosstalk between adjacent channels.     

Novel current-mode background suppression for 2-D LWIR applications

A new readout circuit involving two-step current-mode background suppression is studied for two-dimensional long-wavelength infrared focal plane arrays (2-D LWIR FPAs). Buffered direct injection (BDI) and a feedback amplifier are used for the input circuit and background suppression circuit, respectively. The readout circuit has been fabricated using a 0.6-/spl mu/m 2-poly 3-metal CMOS process for a 64/spl times/64 LWIR HgCdTe IR array with a pixel size of 50 /spl mu/m/spl times/50 /spl mu/m. The simple pixel circuit has a very small skimming error of less than 0.3% and low noise characteristics for an adequate calibration range and integration time.     

An auto-I/Q calibrated CMOS transceiver for 802.11g

The CMOS transceiver IC exploits the superheterodyne architecture to implement a low-cost RF front-end with an auto-I/Q calibration function for IEEE 802.11g. The transceiver supports I/Q gain and phase mismatch auto tuning mechanisms at both the transmitting and receiving ends, which are able to reduce the phase mismatch to within 1/spl deg/ and gain mismatch to 0.1dB. Implemented in a 0.25 /spl mu/m CMOS process with 2.7 V supply voltage, the transceiver delivers a 5.1 dB receiver cascade noise figure, 7 dBm transmit, and a 1 dB compression point.     

On the performance analysis and design of an integrated front-end PIN/HBT photoreceiver

A detailed study on the performance analysis and optimum design of an integrated front-end PIN/HBT photoreceiver for fiber-optic communication is presented. Receiver circuits with two different transimpedance amplifiers-a single-stage common emitter (CE) amplifier and a three-stage amplifier comprising a CE amplifier and two emitter followers (EFs), are analyzed assuming a standard load of 50 /spl Omega/. A technique to include the transit-time effect of a PIN photodetector on the overall receiver circuit analysis is introduced and discussed. Gain-bandwidth product (GB) and gain-bandwidth-sensitivity measure product (GBS) are obtained as functions of feedback resistance (R/sub F/) and various device parameters. Hence, some optimum designs are suggested using a photodetector of area 100 /spl mu/m/sup 2/ and with a feedback resistance of 500 /spl Omega/. The bandwidth plays a major role in determining the optimum designs for maximum GB and maximum GBS. A bandwidth >8 GHz has been obtained for the photoreceiver even with a single-stage CE amplifier. The optimum design for a receiver with a three-stage amplifier shows a bandwidth of 35 GHz which is suitable for receivers operating well beyond 40 Gb/s; however, in this case, the gain is reduced. The performance of different fixed square-emitter structures are investigated to choose the optimum designs corresponding to different gains. Very low power dissipation has been estimated for the optimized devices. The noise performance of the devices with optimum designs was calculated in terms of the minimum detectable optical power for a fixed bit-error rate of 10/sup -9/. The present design indicates that GB and noise performance can be improved by using an optimum device design.     

A 32-GHz non-uniform distributed amplifier in 0.18-/spl mu/m CMOS

This letter presents a fully integrated distributed amplifier in a standard 0.18-/spl mu/m CMOS technology. By employing a nonuniform architecture for the synthetic transmission lines, the proposed distributed amplifier exhibits enhanced performance in terms of gain and bandwidth. Drawing a dc current of 45mA from a 2.2-V supply voltage, the fabricated circuit exhibits 9.5-dB pass-band gain with a bandwidth of 32GHz while maintaining good input and output return losses over the entire frequency band. With a compact layout technique, the chip size of the distributed amplifier including the testing pads is 940/spl times/860/spl mu/m/sup 2/.     

CMOS switched capacitor liquid crystal driver

A novel analogue drive circuit for a liquid crystal cell has been designed. The design was realised in a 0.5 /spl mu/m CMOS process and eight phase-locked channels with independent voltage control were developed. The channels were shown to produce over 5.6/spl pi/ optical phase shift using a /spl plusmn/2.5 V power supply. This drive circuit is proposed for use in portable battery operated applications where optical phase control is desired