Current mirror for bipolar current

The Howland circuit is OK at low currents.

For higher current stuff, this is an interesting starting point:

ftp://66.117.156.8/Isource.JPG

John

Ughhh! Interesting to whom ?:-)

Has the OP specified compliance, or actual current values?

...Jim Thompson

This one only shows up on my machine as a blank page ...

Jim

Then you are doing something wrong. I downloaded it and it opened, with no problem. 12 pages, 233,107 bytes.

It works fine for me. Bob Pease seems to have done a good job (again) and his circuit diagrams are a little tidier than usual.

I'm surprised to see that I'm agreeing with Michael A.Terrell, but then again, this doesn't involve politics.

-- Bill Sloman, Nijmegen

Probably a higher version of Adobe than you have.

I downloaded it. I have the capability to save it as Adobe v4, if you'd like, and post or E-mail it to you. Let me know.

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at

Another method is to use an OTA, e.g. the LM13700. If you bias the input diodes, you can put your bipolar current into either input, and have a reasonable facsimile come out.

Cheers,

Phil Hobbs

Me. I've sold $7e6 or so worth of stuff with this architecture.

John

And then sent a big chunk of that on to Cornell?

A friend has a license plate frame: My daughter and my $$$ are going to UC San Diego.

Maybe it's blocked for Grass Valley residents by some distant attorney general :-)

Interesting that they call that Howland current pump. I thought a pump is the kind of stuff I have the distinct pleasure to clean out this evening. Not looking forward to that.

Yup. But she's working for me now, so I'm taking it out of her hide.

And I did learn how to play beer pong, so it wasn't a total waste.

John

Our downstairs bathroom is below street level, and it has a sump and pump. I've replaced it once. There's a discreet sign near the downstairs toilet, "liquids only."

John

schrieb im Newsbeitrag news: snipped-for-privacy@m73g2000hsh.googlegroups.com...

Hello,

You asked for a "diamond"-transistor (TI, OPA660).

Best regards, Helmut

Mine ain't that gross. It's the pool which is having some algae issues since the wildfires. Chlorinated up to wazoo but there is still stuff raining down into it, as evidenced by patio tables that need to be wiped down daily :-(

Hey, that looks like my transconductance amp.

Yes, I like to live dangerously ;-)

Tim

I saw one at a cafe in China that had a not-very-discreet sign that said (the English part) something like "No s*it-- Y50 must pay if do". I can think of times the $7.50 would be a worthwhile investment. Best regards, Spehro Pefhany

Fine for a power amplifier, not so swift for an _accurate_ bipolar current source.

BTW, I was using that architecture around 1970 to make LDO regulators for the TOW missile.

...Jim Thompson

Bit on the butt again by a switch on the OS that I can't find. If a site is a pure pdf, it doesn't bother telling me about it, but downloads it directly to my download folder rather than asking me if I want to view it directly. If I forget that it MIGHT be a pdf then I don't go looking for it in that download folder. Damn. Downloaded three copies of it and they all came through just fine.

Thanks anyway, Jim, even if you ARE one step to the right of Attila the Hun {;-)

Jim

-- "It is the mark of an educated mind to be able to entertain a thought without accepting it." --Aristotle

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

Brings up a question: In my case (Firefox) most PDF show up right in the browser, some others randomly go the download path. What gives? It seems pretty much willy-nilly.

Then he'd have to be a lifetime NRA member :-)