The Design Of Frequency Synthesizer IN CMOS RF Transceiver

Recently years,with the rapid development of communication and electronic technology,especially in Radio Frequency communication,portable terminal and 5th generation wireless systems Base on Radio Frequency communication technology RF integrated circuit chip had realize more break through and improve.Tire Pressure Monitoring System(TPMS)chip had apply to the car's safety system.It could be monitoring the datas of tire pressure to center control system in timely that decrease the accident and avoid more tragedy.For specific TPMS applications,it has completed the research and design of frequency synthesizers used in tire pressure monitoring chips.Based on the principle of TPMS RF transceiver chip,a double loop charge pump phase-locked loop frequency synthesizer structure is adopted,including a transmit loop,a receive loop,and an auxiliary loop,which effectively improves the frequency of the frequency synthesizer circuit.It will be improving frequency reliability.To support 433MHz and 915MHz dual-mode frequency band output,Ring VCO and LC VCO dual-oscillation circuit are designed to achieve wide frequency range adjustment;in order to achieve multi-channel output of frequency synthesizer,this paper A high speed programmable divider circuit was designed with a maximum divider ratio of 1023.The frequency synthesizer can achieve eight-speed output oscillation frequency continuously adjustable,support 433MHz,915MHz dual-mode operation,and provide a stable four quadrature I/Q signal output.The pre-simulation of the frequency synthesizer and Layout design was completed based on the Cadence application platform,Simulation results show that the frequency synthesizer can work in 433MHz,915MHz dual-mode band,the output frequency can be tuned to 300MHz,500MHz.The phase noisenormalized fitting indicators:-90dBc/@1MHz?-110dBc/@1MHz,and the lock time was 40us and 60us.Static power consumption was 16.5mW.Based on GSMC.18 1P6M process conditions,the overall layout area of the chip about 1860um×1870um,frequency synthesizer about 837um×546um.The measured results show that the TPMS chip's parameters in the 433MHz and 915MHz operating modes are basically accordance in application requirements.