Datasheet needed

If you know the manufacturer, find their website and use their search capabilities.

I have Plessey's TDA1085C datasheet. Presumably that's a more advanced version of their phase-control motor controller chip.

BTW, Mitel bought GEC Plessey, then I think Zarlink bought the line, and has now discontinued it... Anyway, you're in luck, ON Semi still makes the TDA1085 in the C version (442 in stock at DigiKey, for only $1.68 each). I have Motorola's TDA1085A and TDA1085C datasheets, if that's of any help. The Plessey 5-page TDA1085C datasheet has a very detailed but very hard- to-understand schematic, while the 12-page ON Semi datasheet has a detailed "block diagram" schematic that looks useful.

The TDA1085 looks like a pretty useful chip. Anyone? You may remember that Motorola's linear ICs went to ON Semi, and the rest of their ICs just went to Freescale. < sigh >

Sadly, it doesn't look so useful at a second glance. While the drawing may have all the necessary elements, conveniently pared down to the essentials, it's so badly drawn as to be nearly useless. The voltages, currents and signals are not arranged top to bottom, up to down or any other sensible way, except to say, "Where's the nearest edge?" to make landfall for a package pinout location. Anyone seeking to design with this IC will have to completely redraw the schematic before getting underway. I do believe that poor documentation like this can help to spell the death knell for a chip.

Haven't seen the "flavor" of the data sheet you have, but here's yet another for you to look at from Motorola.

I'll hazard a guess Motorola documentation may be "slightly" better.

Thanks, Steve