Hello guys,
One of my customers is evaluating UCC3817 using TI official EVM.
They calcurated Rsense(R14 in Figure 9 on page 16 of the device datasheet) value with the design procedure document in the following URL
and they for the calculated value resistor for R14.
UCC3817: design of 1.5kw Boost pfc
https://e2e.ti.com/support/power-management/f/196/p/769506/2846576?tisearch=e2e-sitesearch&keymatch=ucc3817 design procedure Mathcad#2846576
.The EVM worked correctly but R14 became very hot. So they want to change R14 resistor value to smaller for reducing the the resistor temperature.
My question is that if R14 value is changed to one tenth of the caluculated value, does UCC3817A not work correctly because R14 voltage is chaged
from 1V to 0.1V? If the answer is yes, why UCC3817 doesn't work? Their peak current is 8A.
Could you please give me your advice or comments?
Your reply would be appreciated.
Best regards,
Kazuya Nakai.