A TEM-cell based method for radiative susceptibility characterization of low-power microcontrollers

Abstract

The recent explosion in the portable electronics market combined with an increasingly hostile electromagnetic environment have intensified the need to include EM Susceptibility design and test methods in applicable low-power IC's. This work presents and applies a "EM-cell based method of testing two key aspecwuiescent current and memory integrity+f the radiative susceptibility of low-power microcontrollers. The units were exposed to radiated EM fields of 20 to loo0 Vlm at various frequencies from 0.1 to loo0 MHz. Significant changes in quiescent current occurred only at field values above 70 V/m, which is a much larger ambient field than the microcontroller is expected to experience when used in personal portable electronics products. RAM was changed only &er illumination by fields of greater than 275 V/m. I. hTRODUCnONHE recent explosion in the portable electronics market combined with an increasingly hostile electromagnetic environment have intensified the need to include EM susceptibility design and test methods in applicable low-power IC's. Typical ambient EM field levels have risen due to the accelerating clock and switching speeds of many digital IC's and the proliferation of electronics in offices, homes, automobiles and airplanes. Meanwhile, the drive to reduce the size and weight of portable electronics has led to the development of low-power IC's which require fewer and smaller batteries than their predecessors. As product size and weight continue to shrink, consumers continue to demand more miniaturization, so additional space in portable electronics is not allotted to EM shielding or extra components for susceptibility control. If the current trends continue, product development cycle time requirements will force design cycles to prominently include susceptibility considerations. At the system level, preventative measures can be implemented, but the susceptibility of the system as a whole can be further improved by the appropriate characterization, prediction and establishment of acceptable susceptibility at the IC and package levels. Comprehensive susceptibility characterization insures that the product functions properly in its intended electromagnetic environThis work was supported by two centers in the Motorola Semiconductor Products Sector: the Advanced Interconnect Systems Laboratories (AISL) and the Microconaoller Technologies Group's Customer-Specified Integrated Circuits (CSIC) Division. 'A. Engel was with AISL, and he is now with CSIC, MD OE50.6501 William Cannon Drive West, Austin TX 78737, 512-891-3994, fax 512-891-4441, e-mail andrew-engel @email.mot.com. *H. Asbrain and M. Mahalingam are with AISL, MD EL615, 2100 E. Elliot Rd., Tempe. AZ 85284, 602-413-4994 and -5672, fax 602-413-4511, e-mail hector-astrain@email.mot.com and mdi-mahalingam@email.mot.com. 3J. Cagle and S. Ledford are with CSIC, MD OE50, 6501 William Cannon Drive West, Austin TX 78737, 512-891-6569 and -3705, fax 512-891and steve-ledford@email.mot.com. 0-7803-3207-5/96/$5.00 0 1996 IEEE 76ment, but the many functions perfo...

The Electromagnetic Compatibility of Integrated Circuits—Past, Present, and Future

“…In the static regime, only high-energy perturbations affected logic levels, while even weak perturbations could affect switching delays and circuit thresholds in the transient regime. An 8-bit microcontroller was disturbed in a TEM cell in [59]. While memory devices required fields as high as 275 V/m to be corrupted, significant changes in quiescent currents appeared above 70 V/m.…”