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An on-chip broadband self-interference canceller based on the electrical balance of hybrid transformers is proposed in this work. A variable inductor based on-chip balanced impedance network is utilized to match the actual antenna impedance varying with frequency. In order to achieve broadband electrical balance, an auxiliary quadrature digital transmitter is used to compensate variations of the antenna impedance with frequency. The proposed technique is demonstrated in a standard 130 nm CMOS 1P8M process and the chip occupies 4.84mm2. The simulation results show that the demonstration achieves isolation of more than 60 dB over a 25 MHz bandwidth with 23 dBm transmitter output power at 2 GHz.

A novel self-turnoff control circuit for program process of one-time programmable (OTP) cell is proposed. Utilizing the current turnoff technology after the breakdown of OTP cell, it lowers the power consumption efficiently compared with traditional structures without turnoff mechanism. In addition, an additional delay circuit is also attached to the self-turnoff circuit to ensure the complete breakdown of OTP cell. The simulation results show that the average power consumption of proposed circuit decreases to about 3nA in the whole program process.

This paper proposes a DC-DC buck converter with all-pass network based passive level shifter in 55nm standard CMOS process, for battery powered portable applications. In order to handle high battery voltages in this advanced standard CMOS process, a passive level shifter based on all-pass network is applied for gate oxide protection. Drain extension is proposed to obtain high breakdown voltage of active region. The proposed buck converter with the passive level shifter works in DCM operation as its load current varies from 0.1–10mA. The buck converter achieves a peak efficiency of 93.7% and 83.8% at 10mA load current, with a supply voltage of 1.8V and 3.7V, respectively.

An ultra low power digital baseband processor for passive UHF RFID tag which is compatible with the protocol of Chinese local standard (840–845 MHz and 920–925 MHz) is presented in this paper. A highly reused register bank and a low-cost sort algorithm are proposed to minimize the power consumption and several other low power techniques are adopted, including low supply voltage, clock gating, and minimum operation frequency. The processor is fabricated in SMIC 0.18 um standard CMOS process and consumes 358 nA at 0.6 V voltage supply according to measured results and occupies only 0.1 mm2 area.

A wide band radio frequency (RF) root-mean-square (RMS) power detector (PD) is presented in this paper. A CMOS rectifier with unbalanced source-coupled pairs and auxiliary capacitors is utilized to constitute the reverse received signal strength indicator (reverse-RSSI) architecture as proposed power detector with operating frequency from 300 MHz to 10 GHz. The auxiliary capacitors are introduced to improve linearity at high input power dramatically. The power detector can be connected to power amplifier without directional coupler due to the capacitor attenuation array. Simulation results show that the maximum detection power is as high as +30 dBm and dynamic range reaches more than 42 dB with ±1 dB error. The proposed power detector is implemented in a standard 180nm CMOS process with 0.113 mm2 core area. The supply voltage is 3.3 V, and its static power consumption is 0.55 mW.

A novel human body channel (HBC) energy harvesting scheme for body sensor networks (BSNs) is proposed in this paper. Human body channel is utilized innovatively as energy transmission medium to reduce the transmission loss dramatically and eliminate influence of shadow effect. Further, a high sensitivity and efficiency rectifier is presented by introducing an effective threshold compensation circuit. Experimental results of the energy harvesting scheme show that it can supply 2-μW power typically at −5 dBm transmitted power and up to 19.5-μW at +7 dBm transmitted power by 30 cm distance of human body channel. The sensitivity of the proposed rectifier is −22.5 dBm with 1-V output voltage. When offering 5-μA output current, the rectifier can achieve 25.87% efficiency. The rectifier is implemented in a standard 0.18-μm CMOS process and operating frequency is 145 MHz.

This paper presents a SAW-less GNSS front-end amplifier with GSM blocker suppression using CMOS directional coupler notch filter. The front-end amplifier is aimed at the GNSS receiver integrated in cellular phones. Based on our proposed CMOS stacked spiral-coupled (SSC) directional coupler working at the frequency of 900MHz as notch filter, the front end amplifier achieves a NF of 1.7dB and a 80.4-dB suppression of the GSM blocker while provides signal gain of 38.6-dB for the GPS L1-band signal.