how to design programmble slew rate control circuit for electronic load

[[email protected]]

I design a electronic load.In const current mode, I need to realize
a programmble current slew rate control.how can I to design this
circuit for it?

 

[Winfield Hill]

[email protected] wrote...

I design a electronic load.In const current mode, I need to
realize a programmble current slew rate control.how can I to
design this circuit for it?

Look up ramps and integrators, and think about current sources
into capacitors.

 

[[email protected]]

I need the circuit by amplifier.
thank you

 

[Winfield Hill]

[email protected] wrote...

I need the circuit by amplifier.

Like I said, ahem: "Look up integrators." Include one inside
your amplifier's feedback loop.

 

[[email protected]]

can you give me a sample circuit,thanks a lot

 

[[email protected]]

can you give me a sample circuit,thanks a lot

 

[Rich Webb]

can you give me a sample circuit,thanks a lot

And the irony is, he's posting via Google. Maybe tragedy, eh?

 

[Robert Latest]

can you give me a sample circuit,thanks a lot

You need an electronics BOOK. Paper with ink on it. A very thin,
cheap, basic one.

robert

 

[Winfield Hill]

[email protected] wrote...

[edited] I'm designing an electronic load. In constant-current
mode, I need to realize a programmble current slew rate control.

Can you give me a sample circuit, thanks a lot.

Here's a simple gain-of-one circuit that follows an input
control voltage, but with a programmable slew rate, using
a programmable transconductance opamp.

.. slew Vs Rs
.. rate o---/\/\---, Programmable Slew Rate
.. programming | by Winfield Hill
.. ,------------+
.. | __ | Vs
.. '--|- \ |/V S = ----- volts/sec
.. | >---| Rs Cs
.. gnd --|+_/ |\
.. | R
.. ,----- | ----/\/\-----,
.. | | Cs |
.. in R | ___| ,---||----+ R
.. o--/\/\--+--|+ \ | __ | ,---/\/\---,
.. | >---+--|- \ | R | __ |
.. gnd --|-__/ | >--+--/\/\--+--|- \ | out
.. / gnd --|+_/ | >---+--o
.. / gnd --|+_/
.. transconductance amp

Example of transconductance opamps are NSC's LM13700, the
original CA3080 or NSC's copy, the LM3080. These are still
available from surplus suppliers (I kept a lifetime supply).
You could also try a Burr-Brown opa660 over a limited range.

 

[Rich Grise]

[email protected] wrote...

[edited] I'm designing an electronic load. In constant-current
mode, I need to realize a programmble current slew rate control.

Can you give me a sample circuit, thanks a lot.

Here's a simple gain-of-one circuit that follows an input
control voltage, but with a programmable slew rate, using
a programmable transconductance opamp.

I've got five bucks that says he comes back and asks for component
values. ;-)

Cheers!
Rich

 

[Rich Grise]

And the irony is, he's posting via Google. Maybe tragedy, eh?

Dood, have you seen the latest version of Google? They've really snazzed
it up, and although the groups interface is still idiotic, they make
it really easy for Joe Scriptkiddie to log in and post context-free
posts.

Feh.
Rich

 

[Winfield Hill]

Winfield Hill wrote...

[email protected] wrote...

[edited] I'm designing an electronic load. In constant-current
mode, I need to realize a programmble current slew rate control.

Can you give me a sample circuit, thanks a lot.

Here's a simple gain-of-one circuit that follows an input
control voltage, but with a programmable slew rate, using
a programmable transconductance opamp.

. slew Vs Rs
. rate o---/\/\---, Programmable Slew Rate
. programming | by Winfield Hill
. ,------------+
. | __ | Vs
. '--|- \ |/V S = ----- volts/sec
. | >---| Rs Cs
. gnd --|+_/ |\
. | R
. ,----- | ----/\/\-----,
. | | Cs |
. in R | ___| ,---||----+ R
. o--/\/\--+--|+ \ | __ | ,---/\/\---,
. | >---+--|- \ | R | __ |
. gnd --|-__/ | >--+--/\/\--+--|- \ | out
. / gnd --|+_/ | >---+--o
. / gnd --|+_/
. transconductance amp

Example of transconductance opamps are NSC's LM13700, the
original CA3080 or NSC's copy, the LM3080. These are still
available from surplus suppliers (I kept a lifetime supply).
You could also try a Burr-Brown opa660 over a limited range.

http://www.national.com/ds.cgi/LM/LM13700.pdf

The heart of this circuit, and the key to its simplicity, is
the transconductance amplifier. While these do indeed allow
for an uncomplicated circuit, there are at least four other
ways to solve the problem using conventional components, but
they're decidedly more complex. I'm sorry to see venerable
transconductance amplifiers headed for that fabled IC heaven
in the sky, but that hasn't completely happened just yet. NSC
reports their parts are in production and are stocked at Arrow,
Future, and Newark. Well, the soic package at Newark, anyway.

 

[Rich Webb]

Dood, have you seen the latest version of Google? They've really snazzed
it up, and although the groups interface is still idiotic, they make
it really easy for Joe Scriptkiddie to log in and post context-free
posts.

Feh.

Feh, indeed! I've no interest in gmail, although I do tip my hat to
their brilliant marketing using artificial scarcity and "invitations."

I'd be content for the Google guys to spend a considerable portion of
eternity in A Bad Place for their truly egregious treatment of the
usenet as a subset of "Google Groups." Extra time added for the poor
implementation, of course.

 

[[email protected]]

Winfield hill,thanks,
I am difficult to see ascii circuit,can you give me a jpg or other
picture format circuit.
send it to my email:[email protected]

 

[Winfield Hill]

[email protected] wrote...

Winfield hill,thanks,
I am difficult to see ascii circuit,can you give me a
jpg or other picture format circuit. send it to my
email:[email protected]

Set your viewer to a non-proportional font like Courier,
or copy the text into an editor where you can view it.

 

[Winfield Hill]

Rich Grise wrote...

[email protected] wrote...

[edited] I'm designing an electronic load. In constant-current
mode, I need to realize a programmble current slew rate control.

Can you give me a sample circuit, thanks a lot.

Here's a simple gain-of-one circuit that follows an input
control voltage, but with a programmable slew rate, using
a programmable transconductance opamp.

I've got five bucks that says he comes back and asks for
component values. ;-)

I imagine he read your comment, so instead he came back asking
for a jpg image by email. Could be a troll. boki?

 

[Fred Bartoli]

[email protected] wrote...

Set your viewer to a non-proportional font like Courier,
or copy the text into an editor where you can view it.

Too much work. Could you please build it for him and then send it him.
He'll pay for the components and as he understand you've passed some time
building it, maybe he'll pay you a coffee too. Or two if he feels generous

 

[[email protected]]

Winfield Hill,thanks.
this circuit is based current controll amp,can you give me a circuit
with general amp(such as:OP270).

 

[Winfield Hill]

[email protected] wrote...

Winfield Hill, thanks.
this circuit is based [on a] current control amp, can you
give me a circuit with [a] general amp (such as: OP270).

They're much more complicated, you're better of with the
ready-made programmable amplifier.

 

[[email protected]]

OTA is difficult to buy,and I have some conventional amp,so I hope use
convertional amp to build it.I very need your help.
email:[email protected]