Jae Joon Chang

Power-Combining Transformer Techniques for Fully-Integrated CMOS Power Amplifiers

Fully integrated CMOS power amplifiers (PAs) with parallel power-combining transformer are presented. For the high power CMOS PA design, two types of transformers, series-combining and parallel-combining, are fully analyzed and compared in detail to show the parasitic resistance and the turn ratio as the limiting factor of power combining. Based on the analysis, two kinds of parallel-combining transformers, a two-primary with a 1:2 turn ratio and a three-primary with a 1:2 turn ratio, are incorporated into the design of fully-integrated CMOS PAs in a standard 0.18-mum CMOS process. The PA with a two-primary transformer delivers 31.2 dBm of output power with 41% of power-added efficiency (PAE), and the PA with a three-primary transformer achieves 32 dBm of output power with 30% of PAE at 1.8 GHz with a 3.3-V power supply.

Highly alignment tolerant InGaAs inverted MSM photodetector heterogeneously integrated on a differential Si CMOS receiver operating at 1 Gbps

The increasing demand for high bandwidth, low latency I/O in gigascale systems is challenging current packaging technology. Optoelectronic I/O offers needed performance, but presents new challenges in mixed signal (digital, analog, optical, RF) design and test. In addition, the integration of OE interconnect must be suitable for high volume, low cost manufacturing of digital systems. This paper explores the heterogeneous integration of very large area, highly alignment tolerant photodetectors onto Si CMOS differential analog receiver circuits to realize noise-tolerant receiver interfaces for high-density interconnection electrical substrates with integrated optical links as well as for fiber optic links. The realization of an optically interconnected microprocessor that employs such a photodetector will also be discussed.

Hybrid optically interconnected microprocessor: an InP I-MSM integrated onto a mixed-signal CMOS analog optical receiver with a digital CMOS microprocessor

This paper presents the results of simultaneously working fully-differential optoelectronic receiver fabricated in Si CMOS with digital SIMD microprocessor on the same die next to analog, optical interface circuitry, the receiver have been hybrid integrated with a thin film InP-based inverted (I)-MSM photodetector and optically tested using external light source modulated by digital input signal. The noise immunity to mixed-signal digital switching noise of the differential receiver has been shown to be good enough to generate 10-9 BER.

Smart photonics: optoelectronics integrated with Si CMOS VLSI circuits

Smart photonics, the integration of optoelectronic devices with electronic circuits and systems, has growing applications in many fields, one of which is computing. An exploration of the opportunities, integration technologies, and some recent results using thin film optoelectronic and electronic device integration with Si CMOS VLSI and GaAs MESFET technologies are presented herein. Applications explored herein include low cost alignment tolerant optoelectronic interconnection links for network inerconnections, smart focal plane array processing through the integration of imaging arrays with sigma delta analog to digital converters underneath each pixel, and three dimensional computational systems using vertical through-Si optical interconnections.