> 24VAC RMS means 34V peak, HA! 24VAC means 38V peak (i.e. after the bulk caps) on my board. Had to change modules because I designed for 34V.
> My question (one among many) is how much do I need to filter the > ripple coming out of the full-wave rectifier? Input ripple is telegraphed to the output as part of its reponse curve - how fast can the switcher respond to a change of input voltage. The switchers I got (Acon modules) want 2Vpp ripple max. > It seems that the lower the average input voltage, the higher the > average efficiency of the regulator is going to be, Hmmm... most I've seen have a "sweet spot" that I'm guessing has to do with the duty cycle of the switcher. But note that the efficiency depends on the quality of the catch diode on output; get the lowest Vf schottky you can, and look for a switcher that has a FET helper for it. > so I would ideally aim to have the largest input ripple possible, > which coincidentally allows me to choose a smaller, cheaper input > capacitor. What I did was put in four smaller caps in a row, which reduces the ripple current through each. That helps keep cost down too. http://www.delorie.com/house/furnace/pcb2/board-full.html _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user