Patent ID: 9157959
Filing Date: 2015-10-13
Classification: G01R,G06F,H03B,H03L

Abstract:
1. A semiconductor device comprising: a plurality of modules; a plurality of delay monitors, wherein each delay monitor includes a ring oscillator having a plurality of gate elements and measures a delay time of said gate elements, and a control unit that determines if a module of the plurality of modules, which is proximate to said delay monitor suffers from aged deterioration, based on the delay time measured by said delay monitor, wherein, of said delay monitors, every two delay monitors disposed near to each other form one pair, wherein a ring oscillator in one delay monitor of said pair continues to oscillate except for a predetermined number of cycles before and after a delay time measurement period and a ring oscillator in the other delay monitor of said pair oscillates only during a delay time measurement period, and said control unit determines if the module suffers from aged deterioration, according to a difference between a delay time measured by said one delay monitor and a delay time measured by said other delay monitor.