__________________ I have to power a network Hub that requires 5v DC at 1A, with up to 2-3A peak currents. I was wondering, is there some way to parallel 7805 regulators to fit this task? (The problem is that I live in Uruguay, an LM 350 costs U$S 7, and I can't just mail order them from Digikey beacuse of new Customs laws.) __________________ The transistor method that other people have suggested works well enough BUT you lose the current limiting and thermal protection of the 7805. You can retain over current protection and thermal protection if you are happy to accept somewhat worse regulation. You can parallel 7805's by placing SMALL resistors in the OUTPUTS with a smoothing capacitor both at the regulator outputs AND at the final combined output. The resistors will make the output slightly lower and reduce the regulation achieved. They should drop say about 0.1 volt at fill current so R = 0.1 V/ 1 Amp = 0.1 ohm. Power dissipated is only 0.1 watt so almost any 0.1 ohm resistor would do. This scheme works by reducing the load on regulators which supply higher currents thereby balancing the overall share of the load to each. if the drop is too low the highest output regulator will not have its output reduced enough to fall below that of the lowest output regulator. test selecting regulators to have as close an output voltage as possible will allow the lowest possible resistors to be used. ((Note that placing resistors in the INPUTS to the regulators does NOT produce current sharing)). With the use of 0.1R load resistors the output voltage will droop about 0.1v more from no load to full load as it would without the resistors. You can parallel 7805s directly without any resistors at all with some success. The higher output voltage regulators will provide more current than the lower output ones until they reach their load limit. at that stage they will start to shut down and reduce their output voltages somewhat allowing the others to take up excess load. This means that some will work harder than others but this is probably acceptable in practice. By the way, quoted printable is what you should AVOID if possible :-). Perfectly readable for me but makes quoting your message more difficult. . Russell McMahon -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body