Calculate average current consumption of Async SRAM

Question: How do I calculate the average current consumed by an Asynchronous SRAM when the SRAM is accessed for only a certain time? (The remaining time in standby mode and this is a repeating sequence)

 

Answer:

For simplification, let's assume a 100ns cycle where 12ns is dedicated for a read or a write operation and for the remaining 88ns, the part is in standby mode. In this case, the average current consumed by the part is (.12 * Icc) + (.88 * Isb). Isb could be either Isb1 or Isb2, depending upon whether the inputs are switching or stationary.