Low-Power Memory Circuits:Conclusion

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Conclusion

In this section, the latest developments in low-power circuit techniques and methods for ROMs, Flash memories, MRAMs, FeRAMs, SRAMs, and DRAMs were reviewed. All major sources of power dissipation in these memories were analyzed. Key techniques for drastic reduction of power consumption were identified. These are capacitance reduction, very low-operating voltages, DC and AC current reduction, and suppression of leakage currents. Many of the reviewed techniques are applicable to other applications such as ASICs, DSPs, etc. Battery and solar-cell operation requires an operating voltage environment in sub-1 V area. These conditions demand new design approaches and more sophisticated concepts to retain high device reliability. Experimental circuits operating at these voltage levels slowly start to emerge in all types of memories. However, there is no universal solution for any of these designs and many challenges still await for memory designers.

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