title: Design and implementation of a RF powering circuit for RFID tags or other batteryless embedded devices.
abstract: A RF powering circuit used in radio-frequency identification (RFID) tags and other batteryless embedded devices is presented in this paper. The RF powering circuit harvests energy from electromagnetic waves and converts the RF energy to a stable voltage source. Analysis of a NMOS gate-cross connected bridge rectifier is conducted to demonstrate relationship between device sizes and power conversion efficiency (PCE) of the rectifier. A rectifier with 38.54% PCE under normal working conditions is designed. Moreover, a stable voltage regulator with a temperature and voltage optimizing strategy including adoption of a combination resistor is developed, which is able to accommodate a large input range of 4 V to 12 V and be immune to temperature variations. Latch-up prevention and noise isolation methods in layout design are also presented. Designed with the HJTC 0.25 μm process, this regulator achieves 0.04 mV/°C temperature rejection ratio (TRR) and 2.5 mV/V voltage rejection ratio (VRR). The RF powering circuit is also fabricated in the HJTC 0.25 μm process. The area of the RF powering circuit is 0.23 × 0.24 mm². The RF powering circuit is successfully integrated with ISO/IEC 15693-compatible and ISO/IEC 14443-compatible RFID tag chips.
authors.affiliation: School of Optical and Electronic Information, Huazhong University of Science & Technology, Wuhan 430074, China. dsliu@mail.hust.edu.cn.
authors.forename: Dongsheng
authors.initials: D
authors.lastname: Liu
authors.affiliation: School of Optical and Electronic Information, Huazhong University of Science & Technology, Wuhan 430074, China. renshinewang@gmail.com.
authors.forename: Rencai
authors.initials: R
authors.lastname: Wang
authors.affiliation: School of Optical and Electronic Information, Huazhong University of Science & Technology, Wuhan 430074, China. keyao@hust.edu.cn.
authors.forename: Ke
authors.initials: K
authors.lastname: Yao
authors.affiliation: School of Optical and Electronic Information, Huazhong University of Science & Technology, Wuhan 430074, China. estxczou@gmail.com.
authors.forename: Xuecheng
authors.initials: X
authors.lastname: Zou
authors.affiliation: School of Optical and Electronic Information, Huazhong University of Science & Technology, Wuhan 430074, China. guolianger@gmail.com.
authors.forename: Liang
authors.initials: L
authors.lastname: Guo
mesh_terms: D011211:Electric Power Supplies; D004867:Equipment Design / Q000295:instrumentation* / Q000379:methods; D057233:Radio Frequency Identification Device / Q000379:methods*; D011846:Radio Waves; D059015:Wireless Technology / Q000295:instrumentation*