【摘要】 给出了一个采用TSMC0.18μm CMOS工艺设计并实现的12路30Gb/s并行光接收前端放大器.电路设计采用RGC结构和噪声优化技术,克服了CMOS光检测器大寄生电容造成的带宽不够的问题.测试结果表明,在2pF的寄生电容下单信道传输速率达到了2.5Gb/s,在0.8mVpp输入下得到了清晰的眼图.提出了一种同时采用p+保护环(PGR)、n+保护环(NGR)和深n阱(DNW)的并行放大器隔离结构,有效地抑制了并行放大器之间的串扰,减小了放大器之间的衬底耦合噪声.测量结果表明,这种结构与PGR和PGR+NGR相比,在1GHz时放大器之间的隔离度分别提高了29.2和8.1dB,在2GHz时放大器之间的隔离度分别提高了8.1和2.5dB.芯片采用1.8V电源供电,单路前端放大器的功耗为85mW,12路总功耗约为1W.更多还原

【Abstract】 This paper presents a 12-channel,30Gb/s front-end amplifier realized in standard 0.18μm CMOS technology for parallel optic-fiber receivers.In order to overcome the problem of inadequate bandwidth caused by the large parasitical capacitor of CMOS photo-detectors,a regulated-cascode structure and noise optimization are used in the design of the transimpedance amplifier.The experimental results indicate that,with a parasitical capacitance of 2pF,a single channel is able to work at bite rates of up to 2.5Gb/s,and a clear eye diagram is obtained with a 0.8mV_ pp input.Furthermore,an isolation structure combined with a p+ guard-ring (PGR),an n+ guard-ring (NGR),and a deep-n-well (DNW) for parallel amplifier is also presented.Taking this combined structure,the crosstalk and the substrate noise coupling have been effectively reduced.Compared with the isolation of PGR or PGR+NGR,the measured results show that the isolation degree of this structure is improved by 29.2 and 8.1dB at 1GHz,and by 8.1 and 2.5dB at 2GHz,respectively.With a 1.8V supply,each channel of the front-end amplifier consumes a DC power of 85mW,and the total power consumption of 12 channels is about 1W.更多还原