This plot uses the LMH6738 high-speed, triple Op Amp’s power derating plot to demonstrate how to consider power dissipation. As you can see, the two curves are for still air and for 225 linear feet per minute forced air which is the specification for the fan used to cool down the device in this case, if used. Assuming 30 milliwatts per video output, the three channels of the LMH6738 will be dissipating about 90 milliwatts due to the load. To that, one must add the 6738’s worst case quiescent dissipation of 400 milliwatts which is the result of 40 milliamps typical supply current with +/-5 volt supplies taken together. The total dissipation and the maximum allowable ambient temperature is graphically estimated for the two cases of still and forced air.