Olin, An awful lot of analog goes on these days in the 0-5V (or less!) world. The days of the ubiquitous +/- 12V or +/- 15V are behind us, I'm afraid. And I agree, a voltage regulator with on a 650mv input voltage range is ridiculous, but the other flavors of the TC1262 are all quite reasonable and have a good reason for their existence. Bob Ammerman RAm Systems ----- Original Message ----- From: "Olin Lathrop" To: Sent: Tuesday, August 19, 2003 2:42 PM Subject: Re: [PIC:] beginner troubles > > what specs "several times" have you looked at? > > > > 21395b.pdf "TC125/TC126 PFM Step-up DC/DC Regulators" tells > > about fixed voltages 3.0V, 3.3V, 5.0V. and others for the > > next apps: > > Palmtops/PDAs, Battery-Operated Systems, Cameras, Portable > > Communicators. > > > > Start-up at 0.9V. > > > > What's wrong with this applications? > > Don't they need to be powered from one or two cells? > > > > 20MHz PIC powered from one cell, why is this ridiculous? > > Certainly there are applications where all the analog voltages are less > than 5.5V, but that's much more limited than 12V or +-15V, for example. > > I was mostly thinking of the opamps and voltage regulators. For example, > I just don't find a lot of use for a TC1262 5V linear regulator. It has a > *typical* 350mV dropout and a max input voltage of 6.0V. That leaves a > whopping 650mV input voltage range from 5.35V to 6.00V. That's like > claiming a perfect mousetrap by redefining the standard mouse. Maybe > there's a circuit out there where that's just the right fit, but I haven't > come accross it yet. > > > ***************************************************************** > Embed Inc, embedded system specialists in Littleton Massachusetts > (978) 742-9014, http://www.embedinc.com > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu > -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu