TMCS1126-Q1: I would like to inquire about the maximum power consumption(TMCS1126-Q1 and UCC21750QDWRQ1)

Hey Junehee, 

Thanks for using E2E!

Maximum Power dissipation by the device is a function of temperature. Have a look at figure 7-4 in the datasheet, as well as section 6.6, and you will see that the current carrying capability of the device diminishes as the ambient temperature increases. 

If you want to calculate the maximum power dissipation for a given temperature, you need to examine the input current as well as the quiescent current of the device. For example, for 125°C, we see that the maximum current for the device is 44A. From section 6.6, we also find the leadframe resistance:

At 125°C, the resistance drift would add a small addition to the 0.7mΩ, so the drift would be (125°C - 25°C) * 2.1uΩ = 210uΩ, so for the input current, the total power contribution would be P=I*I*R = 44*44*(0.0007+0.00021) = 1.76W

For the quiescent current, this would be based on your supply voltage. For a 5V supply, worst case current at 125°C is 14.5mA, so 5*0.0145 = .0725W

So, maximum power dissipation at 125°C would be 1.83W. You can repeat this calculation for any temperature. 

Please let me know if this makes sense. In the meantime, I will loop in the appropriate team to help with the UCC21750.