cupoftea
Advanced Member level 6
Hi,
Whilst running 70W CCM flybacks on 240VAC, it was noted that when a BCM flyback (but in const frequency) has its secondary inductance increased so that it goes just into CCM, you dont suddenly see a sudden decrease in efficiency due to the reverse recovery. Even though it was using Ultra fast sec diode and not SiC.
I mean, we took it so that the primary turned on when sec was still conducting 200mA or so, and no appreciable difference in efficiency was seen.
I am wondering if there is some marketing going on, over-stating the benefit of BCM flyback chips?
Would like to do a 70W offline flyback in deep CCM for comparison, wonder what we would see efficiency wise?
Approx 10% worse effciency than BCM?.....1% worse efficiency?
Whilst running 70W CCM flybacks on 240VAC, it was noted that when a BCM flyback (but in const frequency) has its secondary inductance increased so that it goes just into CCM, you dont suddenly see a sudden decrease in efficiency due to the reverse recovery. Even though it was using Ultra fast sec diode and not SiC.
I mean, we took it so that the primary turned on when sec was still conducting 200mA or so, and no appreciable difference in efficiency was seen.
I am wondering if there is some marketing going on, over-stating the benefit of BCM flyback chips?
Would like to do a 70W offline flyback in deep CCM for comparison, wonder what we would see efficiency wise?
Approx 10% worse effciency than BCM?.....1% worse efficiency?