The current consumption values specified in the Electrical Characteristics table can be used to calculate the total power dissipation and IC power dissipation for any device configuration. The total V_CC core supply current (I_{CC_TOTAL}) can be calculated using Equation 5:

where

• I_{CC_CORE} is the current for core logic and input blocks and depends on selected input (CLKinX or OSCin).
• I_{CC_BANK_A} is the current for Bank A.
• I_{CC_BANK_B} is the current for Bank B.
• I_{CC_CMOS} is the current for the LVCMOS output (or 0 mA if REFout is disabled).

Because the output supplies (V_CCOA, V_CCOB, V_CCOC) can be powered from 3 independent voltages, the respective output supply currents (I_{CCO_BANK_A}, I_{CCO_BANK_B}, and I_{CCO_CMOS}) should be calculated separately. I_{CCO_BANK} for either Bank A or B can be directly taken from the corresponding output supply current spec (I_{CCO_HCSL}) provided the output loading matches the specified conditions. Otherwise, I_{CCO_BANK} should be calculated as follows:

where

• I_{BANK_BIAS} is the output bank bias current (fixed value).
• I_{OUT_LOAD} is the DC load current per loaded output pair.
• N is the number of loaded output pairs per bank (N = 0 to 4).

Table 9-1 shows the typical I_{BANK_BIAS} values and I_{OUT_LOAD} expressions for HCSL.

Once the current consumption is calculated for each supply, the total power dissipation (P_TOTAL) can be calculated as:

If the device configuration is configured with HCSL outputs, then it is also necessary to calculate the power dissipated in any termination resistors (P_{RT_HCSL}). The external power dissipation values can be calculated as follows:

Finally, the IC power dissipation (P_DEVICE) can be computed by subtracting the external power dissipation values from P_TOTAL as follows:

where

• N₂ is the number of HCSL output pairs with termination resistors to GND.