Design of Low Power and Low Phase Noise Current Starved Ring Oscillator for RFID Tag EEPROM

Abstract

Power dissipation of CMOS IC is a key factor in low power applications especially in RFID tag memories. Generally, tag memories like electrically erasable programmable read-only memory (EEPROM) require an internal clock generator to regulate the internal voltage level properly. In EEPROM, oscillator circuit can generate any periodic clock signal for frequency translation. Among different types of oscillators, a current starved ring oscillator (CSRO) is described in this research due to its very low current biasing source, which in turn restrict the current flows to reduce the overall power dissipation. The designed CSRO is limited to three stages to reduce the power dissipation to meet the specs. The simulated output shows that, the improved CSRO dissipates only 4.9 mW under the power supply voltage (VDD) 1.2 V in Silterra 130 nm CMOS process. Moreover, this designed oscillator has the lowest phase noise -119.38 dBc/Hz compared to other research works. In addition, the designed CSRO is able to reduce the overall chip area, which is only 0.00114 mm 2 . Therefore, this proposed low power and low phase noise CSRO will be able to regulate the voltage level successfully for low power RFID tag EEPROM. Načrtovanje tokovno omejenga oscilatorja nizkih moči in nizkega faznega šuma za RFID EEPROM nalepkeIzvleček: Poraba moči CMOS IC je izredno pomembna pri napravah nizkih moči, posebej še pri spominu RFID nalepk. V spošnem, spomin nalepk, kot je elektronsko izbrisljiv in programirljiv EEPROM, potrebuje generator interne ure za reguliranje internega napetostnega nivoja. Poleg številnih tipov osclatorjev je v članku opisan tokovno omejen obročni oscilator (CSRO), saj zaradi omejitve toka, ki zmanjšuje porabo moči. Načrtan CSRO uporablja tri stopnje za doseganje specificirane porabe moči. Simuliran oscilator potrebuje 4,9 mW pri napajalni napetosti 1,2 V in realizaciji v 130 nm Silterra CMOS tehnologiji. V primerjavi z drugimi oscilatorji ima najnižji fazni šum -119,38 dBc/Hz in majhno površino 0,001144 mm 2 . Predlagan oscilator je sposoben regulirati napetost EEPROM RFID nalepk.