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There is a dynamic random access memory (DRAM). (1) What is the minimum capacitance of Cs to have higher than 3 V of Vf after READ operation? Assume Vs = 3.3 V, C Cbit is 1 fF. (2) DRAM requires refresh process because leakage makes the voltage at Cs decrease. What is the minimum refresh period to sustain the voltage Vs higher than 3.0 V ? Assume the leakage current is 1 nA, and Css is 20 fF. Ignore voltage decrease by charge sharing.

There is a dynamic random access memory (DRAM). (1) What is the minimum capacitance of Cs to have higher than 3 V of Vf after READ operation? Assume Vs = 3.3 V, C Cbit is 1 fF. (2) DRAM requires refresh process because leakage makes the voltage at Cs decrease. What is the minimum refresh period to sustain the voltage Vs higher than 3.0 V ? Assume the leakage current is 1 nA, and Css is 20 fF. Ignore voltage decrease by charge sharing.

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  1. There is a dynamic random access memory (DRAM). (1) What is the minimum capacitance of C s to have higher than 3 V of V f after READ operation? Assume V s = 3.3 V , C Cbit is 1 f F . (2) DRAM requires refresh process because leakage makes the voltage at C s decrease. What is the minimum refresh period to sustain the voltage V s higher than 3.0 V ? Assume the leakage current is 1 n A , and C s s is 20 f F . Ignore voltage decrease by charge sharing.

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