cupoftea
Advanced Member level 5
Hi,
We have a CCM Boost PFC (ML4800 controller) from an external agency that needs Pout=1024W. Vac input = 110-25VAC. Vout = 400VDC. (As per LTspice sim attached)
It is seen to have a 0.0375R sense resistor (Two pieces of 5%, 0.075R, 3W axials in parallel).
The ML4800 sense ref voltage is 1V….as such, the current peak threshold limit, is set to 26.7A. This is way above the 20A peak which would occur at 110VAC input and max load. Why have they set the peak current threshold of the PFC so high?
Also, why does it use (vertical mounted) axial resistors for PFC current sense?
{Boost PFC inductor is two stacked Mag Inc “Kool mu” 0076076A7 torroids with 42 Turns (184uH at zero current and 100uH at 20A.)}
We have a CCM Boost PFC (ML4800 controller) from an external agency that needs Pout=1024W. Vac input = 110-25VAC. Vout = 400VDC. (As per LTspice sim attached)
It is seen to have a 0.0375R sense resistor (Two pieces of 5%, 0.075R, 3W axials in parallel).
The ML4800 sense ref voltage is 1V….as such, the current peak threshold limit, is set to 26.7A. This is way above the 20A peak which would occur at 110VAC input and max load. Why have they set the peak current threshold of the PFC so high?
Also, why does it use (vertical mounted) axial resistors for PFC current sense?
{Boost PFC inductor is two stacked Mag Inc “Kool mu” 0076076A7 torroids with 42 Turns (184uH at zero current and 100uH at 20A.)}