This example shows how to calculate IC power dissipation for a configuration to estimate worst-case power dissipation. In this case, the maximum supply voltage and supply current values specified in Section 6.5 are used.

• V_CC = V_CCO = 3.465 V. Maximum I_CC and I_CCO values.
• CLKin0/CLKin0* input is selected.
• Banks A and B are enabled: all outputs terminated with 50 Ω to GND.
• REFout is enabled with 5-pF load.
• T_A = 85°C

Using the power calculations from the previous section and maximum supply current specifications, we can compute P_TOTAL and P_DEVICE.

• From Equation 5: I_{CC_TOTAL} = 10.5 mA + 38.5 mA + 38.5 mA + 5.5 mA = 93 mA
• From I_{CCO_HCSL} maximum spec: I_{CCO_BANK_A} = I_{CCO_BANK_B} = 84 mA
• From Equation 7: P_TOTAL = 3.465 V × (93 mA + 84 mA + 84 mA + 10 mA) = 939 mW
• From Equation 8: P_{RT_HCSL} = (0.92 V) 2 / 50 Ω = 16.9 mW (per output pair)
• From Equation 9: P_DEVICE = 939 mW – (8 × 16.9 mW) = 803.8 mW

In this worst-case example, the IC device will dissipate about 803.8 mW or 85.6 of the total power (939 mW), while the remaining 14.4% will be dissipated in the termination resistors (135.2 mW for 8 pairs). Based on θ_JA of 31.4°C/W, the estimated die junction temperature would be about 25.2°C above ambient, or 110.2°C when T_A = 85°C.