Prediction of Aging Impact on Electromagnetic Susceptibility of an Operational Amplifier

He Huang (1) , Alexandre Boyer (1) , Sonia Ben Dhia (1) , Bertrand Vrignon (2)

1 LAAS-ESE - Équipe Énergie et Systèmes Embarqués
2 Freescale Semiconductor

This paper deals with the impact of aging on the electromagnetic susceptibility level of a CMOS operational amplifier (opamp). The aging impact can be modelled by the variation of several parameters of the MOSFET model, to predict the evolution of electromagnetic susceptibility (EMS) of the opamp block during the aging process. I. INTRODUCTION The increasing use of high speed and complex electronic systems makes the electromagnetic compatibility (EMC) an important issue for the electronic manufacturers [1]. Some experimental results show the significant reduced EMC evolution after aging stress [2]. Thus how to ensure EMC during the whole lifetime of IC products, which is called electromagnetic robustness (EMR), becomes a new study in the recent years. As presented in only few works, the simulation can be used to predict the long-term EMC behaviour. For example, in [3], the increase of the electromagnetic emission of a DC-DC converter after thermal stress is modeled, which is associated to the degradation of filtering passive devices. In [4], the simulation results confirm the evolution of the EMS of a phase-locked loop (PLL) before and after aging. The aging affects the threshold voltage and the mobility of the MOSFET of the PLL. However, in these case studies only two statuses (the device before and after a period of aging) are measured and simulated. Thus there is a lack of more precise insight about the evolution of the different phases during the whole aging time. As a common electronic block, the operational amplifier is very susceptible to the external electromagnetic interference (EMI). The coupling of EMI on opamp inputs and power supply leads to a distortion of the output voltage, especially the generation of a voltage offset on its output which is harmful and hard to remove [5], [6]. In this study, with the aging stress injected in several parts of the amplifier, a worse DC output offset value at several frequencies could be observed, that means the device becomes more susceptible to the EMI with the aging. So the prediction of EMS evolution becomes important to help the IC designers to prevent EMC failure during the ICs' lifetime.

Domaines: Electronique

He Huang, Alexandre Boyer, Sonia Ben Dhia, Bertrand Vrignon. Prediction of Aging Impact on Electromagnetic Susceptibility of an Operational Amplifier. Asia-Pacific International EMC Symposium 2015, May 2015, Taipei, Taiwan. 4p. ⟨hal-01159222⟩