60 likes | 305 Views
A 0.6V 205MHz 19.5ns tRC 16Mb Embedded DRAM. K. Hardee, F. Jones, D. Butler, M. Parris, M. Mound, H. Calendar, G. Jones, L. Aldrich, C. Gruenschlaeger, M. Miyabayashi, K. Taniguchi, T. Arakawa. Overview. Primary use Embedded DRAM Uniqueness claim
E N D
A 0.6V 205MHz 19.5ns tRC 16MbEmbedded DRAM K. Hardee, F. Jones, D. Butler, M. Parris, M. Mound, H. Calendar, G. Jones, L. Aldrich, C. Gruenschlaeger, M. Miyabayashi, K. Taniguchi, T. Arakawa
Overview • Primary use • Embedded DRAM • Uniqueness claim • Ultra-low supply voltage (0.6V) for low power consumption • Difficulties of low voltage operation • Reduced transistor thresholds cause greater off current • At low voltages, circuit speed is more dependent on manufacturing variations • Low voltages make bitline sensing more difficult
Overview (continued) • Solution #1 • Current through reference transistor is monitored and body bias is regulated to increase Vt during quiescent periods • Improves speed for slow process conditions by 63% • Reduces leakage current by 75% • Solution #2 • A sleep mode is introduced that further reduces leakage current • Solution #3 • Extra low Vt (0.2V) transistors are used to provide low-voltage sensing for bitlines