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Yibo JIANG Hui BI Wei ZHAO Chen SHI Xiaolei WANG
For the RF power amplifier, its exposed input and output are susceptible to damage from Electrostatic (ESD) damage. The bi-direction protection is required at the input in push-pull operating mode. In this paper, considering the process compatibility to the power amplifier, cascaded Grounded-gate NMOS (ggNMOS) and Polysilicon diodes (PDIO) are stacked together to form an ESD clamp with forward and reverse protection. Through Transmission line pulse (TLP) and CV measurements, the clamp is demonstrated as latch-up immune and low parasitic capacitance bi-direction ESD protection, with 18.67/17.34V holding voltage (Vhold), 4.6/3.2kV ESD protection voltage (VESD), 0.401/0.415pF parasitic capacitance (CESD) on forward and reverse direction, respectively.
Chee Yik KEONG Poo Kuan HOONG Choo-Yee TING
In this paper, we propose an adaptive chunk scheduling for mesh-based peer-to-peer live streaming system, a hybrid class of push and pull chunk delivery approach. The proposed rule-based push-pull scheduler simultaneously pull video chunk from lower latency peers to fill up missing chunks and push video chunk adaptively for rapid chunk delivery. We performed comparative simulation study against rarest first push-pull and status-wise push-pull to prove the efficiency of our proposed algorithm. Mesh-push is made possible by effectively exploiting the information through buffer map exchange. The findings of performance evaluation have suggested a better video continuity and achieved lower source to end delay.
Duhwan JO Sumi HELAL Eunsam KIM Wonjun LEE Choonhwa LEE
This paper presents novel hybrid push-pull protocols for peer-to-peer video streaming. Our approaches intend to reap the best of push- and pull-based schemes by adaptively switching back and forth between the two modes according to video chunk distributions. The efficacy of the proposed protocols is validated through an evaluation study that demonstrates substantial performance gains.
Hai-Han LU Shah-Jye TZENG Wen-Jen WANG Hsiang-Chun PENG Ching-Yi CHEN
A directly modulated AM-VSB CATV erbium-doped fiber amplifier (EDFA)-repeated system that uses push-pull modulated distributed feedback (DFB) laser diodes and half-split-band technique is proposed and demonstrated. Push-pull modulation scheme enhances the frequency response of the laser diode, and thus improves the overall performance of the fiber optical CATV systems. Good performances of carrier-to-noise ratio (CNR), composite second order (CSO), and composite triple beat (CTB) were achieved for the full channel band over a 100-km single-mode fiber (SMF) transport.
Kawori TAKAKUBO Hajime TAKAKUBO Shigetaka TAKAGI Nobuo FUJII
Voltage follower is one of the most useful building blocks in analog circuits. This paper proposes a voltage follower composed of a complementary pair of p-channel MOS(PMOS) and n-channel MOS (NMOS) differential amplifiers which operates under low power supply. The proposed circuit has a rail-to-rail dynamic range by combining complementary differential amplifiers.
Masahito SHOYAMA Kuniyasu HORIKOSHI Tamotsu NINOMIYA Toshiyuki ZAITSU Yasuhiro SASAKI
Steady-state characteristics of the push-pull inverter with a piezoelectric transformer are analyzed. The piezoelectric transformer operating in the 3rd-order longitudinal vibration mode is used in place of a conventional magnetic transformer to produce a high output voltage to light up a cold cathode fluorescent lamp. The circuit operation, the load characteristics, the efficiency and the ZVS conditions are analyzed using equivalent circuits. These analytical results are confirmed by experiments. An example of the output current control is also shown.
Isao TAKENAKA Hidemasa TAKAHASHI Kazunori ASANO Kohji ISHIKURA Junko MORIKAWA Hiroaki TSUTSUI Masaaki KUZUHARA
This paper describes a high-power and low-distortion AlGaAs/GaAs HFET amplifier developed for digital cellular base station system. We proved experimentally that distortion characteristics such as IMD (Intermodulation Distortion) or NPR (Noise Power Ratio) are drastically degraded when the absolute value of the drain bias circuit impedance at low frequency are high. Based on the experimental results, we have designed the drain bias circuit not to influence the distortion characteristics. The developed amplifier employed two pairs of pre-matched GaAs chips mounted on a single package and the total output-power was combined in push-pull configuration with a microstrip balun circuit. The push-pull amplifier demonstrated state-of-the-art performance of 140 W output-power with 11.5 dB linear gain at 2.2 GHz. In addition, it exhibited extremely low distortion performance of less than 30 dBc at two-tone total output-power of 46 dBm. These results indicate that the design of the drain bias circuit is of great importance to achieve improved IMD characteristics while maintaining high power performance.
Jae-Yoon SIM Cheol-Hee LEE Won-Chang JEONG Hong-June PARK
A fully differential folded cascode CMOS OP amp is combined with an adaptive bias OTA to increase the slew rate, and a continuous-time CMFB circuit with a push-pull type combination of a NMOS input and a PMOS input differential amplifiers is used to maximize the output voltage swing. The fabricated OP amp using a 0.8 µm digital CMOS process gives more than three times improvement in slew rate with a 15% increase in DC power consumption and a 7.5% increase in chip area compared to the conventional OP amp fabricated on the same die. The output voltage swing was measured to be -0.75 V -0.7 V at the supply voltage of +/-1.2 V.