I/O power is dependent not only on the device and activity, but also the load being driven. For loads with CMOS inputs, the power required to drive the trace dominates, and is a better measure of load than the number of inputs of lumped load capacitance. If the target system has very different I/O loading, scale the spreadsheet results either up or down to compensate. For this reason, the spreadsheet allows you to specify the approximate load on the I/O pins for each module by using the trace length field. This parameter is used to adjust the reported I/O power numbers.