Xi FU Yun WANG Zheng LI Atsushi SHIRANE Kenichi OKADA
There are enlarged requirements of millimeter-wave beamforming phased-array transceivers and high-order modulation multi-input multi-output (MIMO) transceivers. High-performance integrated RF switches are regarded as one of the most critical components for those transceivers to support signal channel distribution and path redundancy. This paper introduces a CMOS high-isolation and low-loss RF switch with a novel switched parallel LC resonance network. The proposed single-pole double-throw (SPDT) RF switch realizes 68dB port isolation and 1.0dB insertion loss with an active area of 0.034mm2. The SPDT RF switch is composed of two series-shunt transistor pairs with body-floating technology and a switched parallel LC network. The network uses a turned-off series transistor to resonate out off-capacitance Coff. The measured output third-order intercept (OIP3) is higher than 21dBm. The proposed SPDT RF switch maintains return losses of all working ports less than 10dB from 8GHz to 20GHz. The high-performance SPDT RF switch is fabricated in standard 65-nm CMOS technology.
Teerachot SIRIBURANON Takahiro SATO Ahmed MUSA Wei DENG Kenichi OKADA Akira MATSUZAWA
This paper presents a 20 GHz push-push VCO realized by a 10 GHz super-harmonic coupled quadrature oscillator for a quadrature 60 GHz frequency synthesizer. The output nodes are peaked by a tunable second harmonic resonator. The proposed VCO is implemented in 65 nm CMOS process. It achieves a tuning range of 3.5 GHz from 16.1 GHz to 19.6 GHz with a phase noise of -106 dBc/Hz at 1 MHz offset. The power consumption of the core oscillators is 10.3 mW and an FoM of -181.3 dBc/Hz is achieved.
Ning LI Kota MATSUSHITA Naoki TAKAYAMA Shogo ITO Kenichi OKADA Akira MATSUZAWA
An L-2L through-line de-embedding method has been verified up to millimeter wave frequency. The parasitics of the pad can be modeled from the L-2L through-line. Measurement results of the transmission lines and transistors can be de-embedded by subtracting the parasitic matrix of the pad. Therefore, the de-embedding patterns, which is used for modeling active and passive devices, decrease greatly and the chip area also decreases. A one-stage amplifier is firstly implemented for helping verifying the de-embedding results. After that a four-stage 60 GHz amplifier has been fabricated in CMOS 65 nm process. Experimental results show that the four-stage amplifier realizes an input matching better than -10.5 dB and an output matching better than -13 dB at 61 GHz. A small signal power gain of 16.4 dB and a 1 dB output compression point of 4.6 dBm are obtained with a DC current consumption of 128 mA from a 1.2 V power supply. The chip size is 1.5 mm 0.85 mm.
Takanori KYOGOKU Junpei INOUE Hidenari NAKASHIMA Takumi UEZONO Kenichi OKADA Kazuya MASU
This paper concerns a new model for estimating the wire length distribution (WLD) of a system-on-a-chip (SoC). The WLD represents the correlation between wire length and the number of interconnects, and we can predict circuit performances such as power consumption, maximum clock frequency, and chip size from the WLD. A WLD model considering core utilization has been proposed, and the core utilization has a large impact on circuit performance. However, the WLD model can treat only a one-function circuit. We propose a new WLD model considering core utilization to estimate the wire length distribution of SoC, which consists of several different-function macroblocks. We present an optimization method to determine each core utilization of macroblocks.
Kenichi OKADA You NOMIYAMA Rui MURAKAMI Akira MATSUZAWA
This paper proposes a dual-conduction class-C VCO for ultra-low supply voltages. Two cross-coupled NMOS pairs with different bias points are employed. These NMOS pairs realize an impulse-like current waveform to improve the phase noise in the low supply conditions. The proposed VCO was implemented in a standard 0.18 µm CMOS technology, which oscillates at a carrier frequency of 4.5 GHz with a 0.2-V supply voltage. The measured phase noise is -104 dBc/Hz@1 MHz-offset with a power consumption of 114 µW, and the FoM is -187 dBc/Hz.
Hiroyuki ITO Hideyuki SUGITA Kenichi OKADA Tatsuya ITO Kazuhisa ITOI Masakazu SATO Ryozo YAMAUCHI Kazuya MASU
This paper proposes high-Q distributed constant passive devices using wafer-level chip scale package (WL-CSP) technology, which can be realized on a Si CMOS chip. A 90directional coupler using the WL-CSP technology has center frequency of 25.6 GHz, insertion loss of -0.5 dB and isolation of -29.8 dB in the measurement result. The WL-CSP technology contributes to realize low-loss RF passive devices on Si CMOS chip, which is indispensable to achieve small-size, cost-effective and low-power monolithic wireless communication circuits (MWCCs).