Powering (or not) a parallel-port-attached DAC

Don't know if it'd work, but since you're ordering parts anyway would a regulated charge pump work? I assume you're not using the control lines; if you diode-or them together with maybe some small resistors to limit & balance the load and set 'em high, they oughta be good for 30-40ma, and if you're using a DAC it shouldn't draw nearly as much power as an R-2R ladder... It's often done with RS-232 gizmos, but I don't see why it wouldn't work on the Parallel port as well. Just a thought (and probably not a good one...) mike Original Message: --------------------------- Date: Tue, 4 Jul 2006 18:35:37 +1200 From: "Ethan Dicks" <ethan.dicks at gmail.com> Subject: Powering (or not) a parallel-port-attached DAC (was Re: Vector Imagery) On 7/4/06, Tony Duell <ard at p850ug1.demon.co.uk> wrote: I know that the "right" way to do it involves active components... given my 95% success with passive components, I was hoping to squeak by. If I could get power and data from the same source (see below), I wouldn't be quite so picky.