3886 Notes
last updated: Friday, 02-Apr-2004 23:22:52 EST

Dave's Homepage audio home The Vifa X3 Preamp Car Audio Shiva! PA Speakers Hafler stuff Phase Linear LM3886 amp lm12 amp

These are design notes, typed up from my notebook. Ugly yes, but they've got some useful tidbits of info for me. Maybe for you too. The 3886 isn't unity gain stable. Reduce the input by the same amount as the gain when doing a parallel mono setup (ie: gain set to 20 with 20K/1K, attenuate thru voltage divider, 20K on top of 1K to ground), with the output connected to the attenuation network connected to the next input. Use 0.22 or 0.1 ohm resistors to balance output and prevent 'current-hogging'. Can be replicated as many times as required for the desired output current. JPEG is here, thanks Rudi. I used to have a bunch of stuff here about a universla PCB for the module that would allow for standalone, bridged or parallel operation depending on the way it was stuffed. It would be a really nice idea, but I've let it go, mainly because of the radically different topoligies needed for a proper bridged or parallel amp compared to the single chip circuit. I have layouts for all 3 options, as well as for a monster amp (300+W@4R) using some special tricks I've developed, but I'm not ready to share that information yet. Dave Paton        |        dave@dpaton.net        |