this also tells me that if I'm running ultra low currents, I can use cxb3070 instead of cxb3590 and not lose too much efficiency. considering cxb3590s are close to twice the cost of a cxb3070, that sounds like a good compromise.The efficiency vs current looks very linear. In real world scenarios(not pulsed) the case temp will be higher for higher current. So even more compression.
Which means we gain more and more efficiency as the drive current is reduced.
thanks robin and supra for the great data