Design And Research Of A Radiation-hardend Phase-locked-loop

Nowadays, the electrical system updates with a high speed of renovation. It hasbeen changing with each passing day. As more and more applications have been putin the aviation area, the circuit radiation hardened technology becomes reallyessential. The radiation effects research and the radiation technology of t he circuit ofclock generator are getting more and more attention. As the core part of a system,the system stability and the reliability would be affected because of theunpredictable fluctuation frequency and the phase deviation of the circuit of clockgenerator. The PLL (phase locked loop) is good as removing the clock delay, what’smore, it could specify a high clock frequency. The PLL has been recognized as oneof the highest radio sensitivity circuits in aircraft electronic system.This paper mainly uses0.18μm technology to design and harden the ChargePump PPL; also it has a test and verification of the integral structure and acomparison of the different reinforcing performances. Firstly, this paper analyzes thestructure and design the submodule of the Charge Pump PPL, provides a model andsets SET sensitivity analys is of every submodule. Especially aim at voltagecontrolled oscillator, according to the different incident energy, nodes and time, itprocesses a quantitative simulate analysis.What else, this paper also inc ludes the hardened design of the Charge PumpPPL. In digital circuit part, as using CMOS technology for the use of phasefrequency detector circuit structure, the TMR has been used to consolidate thecircuit. Based on the well understanding with the two models, the voltage-basedcharge pump is selected as the final scheme. Voltage controlled oscillator usesredundantcy bias circuit and increasing the ring oscillator series as hardened designplan. The result of Charge Pump PPL circuit simulation and verification is correct.The technique parameter is as follows: The center frequency is1GHz, the gain ofvoltage-controlled oscillator is1.2GHz/V, with a0.4-1.5GHz band range. Afterconsolidation, the maximum phase shift and the recovery time both decrease with60.039%and37.826%. In the end, after designing the layout of the hardened PPL,the result is proved; it is as same as the last emulation one: The center frequency is1GHz, the gain of voltage-controlled oscillator is1.2GHz/V, with a0.4-1.5GHzband range.