Something for Joerg, maybe

formatting link

martin

Reply to
Martin Griffith
Loading thread data ...

Wow, that 'typical application' internal schematic is a new low for LTC. What is it, germanium?

Cheers,

Phil Hobbs

Reply to
Phil Hobbs

formatting link

Don't have a clue (quite normal).

martin

Reply to
Martin Griffith

Thanks, but rather not. Quote "Using series resistance between the power supply and the input of the LT3085 also stabilizes the application. As little as 0.1? to 0.5?, often less, is all that is needed to provide damping in the circuit. If the extra impedance between the power supply and the input is unacceptable, placing the resistors in series with the capacitors will provide damping to prevent the LC resonance from causing full-blown oscillation."

--
Regards, Joerg

http://www.analogconsultants.com/
 Click to see the full signature
Reply to
Joerg

formatting link

That sounds quite technical :)

martin

Reply to
Martin Griffith

formatting link

I had to try

One day they will make one that you like :)

martin

Reply to
Martin Griffith

What's the bet they have a patent pending? :->

Dave.

Reply to
David L. Jones

formatting link

You don't believe the NPN output transistor symbol?

John

Reply to
John Larkin

formatting link

Maybe. But then it should not cost $2 and show zero stock at Digikey ;-)

Possibly someone should teach the movers and shaker in the semi biz to hit the ground running and not come out of the gate too slow.

--
Regards, Joerg

http://www.analogconsultants.com/
 Click to see the full signature
Reply to
Joerg

formatting link

NPNs are too liberal ...

--
SCNR, Joerg

http://www.analogconsultants.com/
 Click to see the full signature
Reply to
Joerg

formatting link

Bipolar weenies!

John

Reply to
John Larkin

formatting link

Can't make the claimed head-room that way ;-)

...Jim Thompson

--
| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
 Click to see the full signature
Reply to
Jim Thompson

formatting link

It can if you pull the base high enough. Which they do.

John

Reply to
John Larkin

formatting link

My bad! Didn't read close enough. You _could_ use a charge pump to accomplish such a task.

...Jim Thompson

--
| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
 Click to see the full signature
Reply to
Jim Thompson

formatting link

Ask CA politicians, they'll tell you how to do it without. Well, at least up to now :-(

--
Regards, Joerg

http://www.analogconsultants.com/
 Click to see the full signature
Reply to
Joerg

formatting link

Charge pumps are so easy to do... I've even utilized them in hearing aids (for the MEMS microphone) and hot-plug circuits.. Could give you LDO without the stability issues, though I'm not sure how well they could respond to transient loads.

...Jim Thompson

--
| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
 Click to see the full signature
Reply to
Jim Thompson

formatting link

LTC.

We recently "invented" the flying-capacitor "isolated" DC power supply, using 300 volt SSRs in a DPDT configuration. They switch slow enough that the spike situation should be pretty good, compared to most dc/dc converters. And no transformers!

It's about time for somebody to make a small laser/pv package as a very quiet isolated power supply.

John

Reply to
John Larkin

formatting link

LTC.

I do things that you discrete guys can't easily do... non-overlapping switches at _every_ stage so that I get phenomenal efficiencies... very important in a hearing aid. Of course having VT=0.45V helps a bunch too ;-)

...Jim Thompson

--
| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
 Click to see the full signature
Reply to
Jim Thompson

formatting link

LTC.

Have you seen Jim Williams AN-70 "A Monolithic Switching Regulator with 100uV Output Noise"? He also trades switching speed (and a bit of efficiency) for low noise.

Reply to
Glen Walpert

formatting link

LTC.

I bet you can't plop a 47 uF low-esr polymer aluminum cap inside one of your ICs. Or optoisolate a switch drive!

Most opto ssr's are break-before-make (slow on, faster off) so a non-overlapping flying cap isolator is easy with just any ole square wave drive, 1 kHz ballpark.

John

Reply to
John Larkin

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.