Title :
Geometry optimization of TMR current sensors for on-chip IC testing
Author :
Le Phan, Kim ; Boeve, Hans ; Vanhelmont, Frederik ; Ikkink, Ton ; Talen, Wim
Author_Institution :
Philips Res. Labs., Eindhoven, Netherlands
Abstract :
In this paper, we demonstrate that tunnel magnetoresistive (TMR) elements can be used as sensitive on-chip current sensors in the microampere to milliampere range for current-based IC testing such as power-pin testing and quiescent Idd current (IDDQ) testing. The sensor can be integrated in CMOS ICs containing magnetic random access memory. TMR current sensors with various lateral dimensions (from submicrometer to micrometer) arranged in a Wheatstone bridge have been realized and analyzed. A typical sensitivity of 2.5(mV/V)/mA and a current resolution of 5.5μA have been observed. The influence of the sensor geometry on sensor sensitivity, hysteresis, and temperature rise due to Joule heating has been investigated.
Keywords :
electric sensing devices; integrated circuit testing; magnetoresistive devices; tunnelling magnetoresistance; TMR current sensors; Wheatstone bridge; electric sensing devices; geometry optimization; magnetoresistive devices; on-chip current sensors; on-chip integrated circuit testing; tunnel magnetoresistive elements; tunnelling magnetoresistance; Bridge circuits; Geometry; Integrated circuit testing; Magnetic analysis; Magnetic hysteresis; Magnetic sensors; Random access memory; Temperature sensors; Thermal sensors; Tunneling magnetoresistance; Current sensor; integrated circuit (IC) testing; magnetic random access memory (MRAM); tunnel magnetoresistance (TMR);
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2005.854813
