ns pulse generator IC for low voltages

O

O. P. E.

Guest
I am trying to make a pulse generator that will generate pulses as
short as 1 ns, with voltages around 1V. It would be triggered by an
external signal. I am wondering whether anyone makes a single chip
solution for this type of thing, or if someone knows a communications
IC that could be easily modified to do this? And it would be great if
it came with an evaluation board, though I realize I am reaching on
that point. (Still, unless you enjoy torture, soldering surface mount
components is something I like to avoid.)

As I've searched on the net, most DIY pulse generator circuits involve
avalanche circuits which seem to require relatively high voltages and
are a little unstable. Linear has a circuit that uses comparators
with an AND gate to produce a pulse, and that seems to be pretty
workable. I've also thought it wouldn't be that hard to combine an
inverter with an AND gate and a delay line IC to produce an output
pulse, provided the transitions didn't excessively widen the pulse.
 
Most logic family edge times are greater than 1ns so aren't going to
work. You might look at ECL - there's a hint here
http://www.elecdesign.com/Articles/Index.cfm?AD=1&ArticleID=3647
There's an article "A recipe for homebrew ECL" by Chuck Hastings
which is a good read, though I couldn't find it on the web.
The avalanche pulser described in the appendix to Linear
application note 79 might be what you want.
http://www.linear.com/pc/downloadDocument.do?navId=H0,C3,P1012,D4168




I am trying to make a pulse generator that will generate pulses as
short as 1 ns, with voltages around 1V. It would be triggered by an
external signal. I am wondering whether anyone makes a single chip
solution for this type of thing, or if someone knows a communications
IC that could be easily modified to do this? And it would be great if
it came with an evaluation board, though I realize I am reaching on
that point. (Still, unless you enjoy torture, soldering surface mount
components is something I like to avoid.)

As I've searched on the net, most DIY pulse generator circuits involve
avalanche circuits which seem to require relatively high voltages and
are a little unstable. Linear has a circuit that uses comparators
with an AND gate to produce a pulse, and that seems to be pretty
workable. I've also thought it wouldn't be that hard to combine an
inverter with an AND gate and a delay line IC to produce an output
pulse, provided the transitions didn't excessively widen the pulse.
 
On Mar 26, 5:51 am, John McMillan <j.e.mcmil...@sheffielddot.acdot.uk>
wrote:
Most logic family edge times are greater than 1ns so aren't going to
work. You might look at ECL - there's a hint herehttp://www.elecdesign.com/Articles/Index.cfm?AD=1&ArticleID=3647
There's an article "A recipe for homebrew ECL" by Chuck Hastings
which is a good read, though I couldn't find it on the web.
The avalanche pulser described in the appendix to Linear
application note 79 might be what you want.http://www.linear.com/pc/downloadDocument.do?navId=H0,C3,P1012,D4168
I appreciate the link to the Linear App Note, as it also had many
details on circuit construction that should really help. I also found
a few other Linear app notes written by Jim Williams. I love how he
has "cartoons" on the last page.

In searching around after I posted here I found Potato Semiconductor
advertising "74 series GHz logic." I've never heard of them before,
but the chips look like they would have the fast response I am looking
for. Does anyone have any experience with them? I also found some
fast chips from OnSemi.

Thanks
 
"O. P. E." <mleigh@gmail.com> wrote in
news:1175018589.604889.292110@r56g2000hsd.googlegroups.com:

In searching around after I posted here I found Potato Semiconductor
advertising "74 series GHz logic." I've never heard of them before,
but the chips look like they would have the fast response I am looking
for. Does anyone have any experience with them? I also found some
fast chips from OnSemi.
Potato chips? Isn't this a few days early? :)
 
In article <1175018589.604889.292110@r56g2000hsd.googlegroups.com>,
"O. P. E." <mleigh@gmail.com> wrote:

On Mar 26, 5:51 am, John McMillan <j.e.mcmil...@sheffielddot.acdot.uk
wrote:
Most logic family edge times are greater than 1ns so aren't going to
work. You might look at ECL - there's a hint
herehttp://www.elecdesign.com/Articles/Index.cfm?AD=1&ArticleID=3647
There's an article "A recipe for homebrew ECL" by Chuck Hastings
which is a good read, though I couldn't find it on the web.
The avalanche pulser described in the appendix to Linear
application note 79 might be what you
want.http://www.linear.com/pc/downloadDocument.do?navId=H0,C3,P1012,D4168


I appreciate the link to the Linear App Note, as it also had many
details on circuit construction that should really help. I also found
a few other Linear app notes written by Jim Williams. I love how he
has "cartoons" on the last page.
If you are going into high speed pulse electronics, you could do
worse than read *everything* that Jim Williams has written.

High-Speed Digital Design: A Handbook of Black Magic
http://www.amazon.com/High-Speed-Digital-Design-Handbook-Black/dp/0133957
241
is good too.

In searching around after I posted here I found Potato Semiconductor
advertising "74 series GHz logic." I've never heard of them before,
but the chips look like they would have the fast response I am looking
for. Does anyone have any experience with them?
I'd never heard of them. Must admit I'd taken my eyes off this field
a bit. The data sheets look great. Has anyone actually used the chips?

I also found some
fast chips from OnSemi.
OnSemi were Motorola who invented ECL (or was it Plessey? or ICL? ...)
Their stuff is good.
 
On Mar 26, 5:51 am, John McMillan <j.e.mcmil...@sheffielddot.acdot.uk>
wrote:
Most logic family edge times are greater than 1ns so aren't going to
work. You might look at ECL - there's a hint herehttp://www.elecdesign.com/Articles/Index.cfm?AD=1&ArticleID=3647
There's an article "A recipe for homebrew ECL" by Chuck Hastings
which is a good read, though I couldn't find it on the web.
The avalanche pulser described in the appendix to Linear
application note 79 might be what you want.http://www.linear.com/pc/downloadDocument.do?navId=H0,C3,P1012,D4168
This app note and a few other app notes and web sites discuss making a
pulse generator with a 2N2369 transistor. It looks like they are
mostly referring to the TO-92 package instead of the surface mount. I
notice that the surface mount usually have a lower power dissipation,
but also would seem to have better RF characteristics due to the
shorter leads. Does anyone have any experience with surface mount vs.
TO-92 for avalanche pulse generation? While I don't like the idea of
soldering surface mount components, I'll do it if I have to.

Thanks
 
In article <1175531755.402669.221410@p77g2000hsh.googlegroups.com>,
"O. P. E." <mleigh@gmail.com> wrote:

On Mar 26, 5:51 am, John McMillan <j.e.mcmil...@sheffielddot.acdot.uk
wrote:
Most logic family edge times are greater than 1ns so aren't going to
work. You might look at ECL - there's a hint
herehttp://www.elecdesign.com/Articles/Index.cfm?AD=1&ArticleID=3647
There's an article "A recipe for homebrew ECL" by Chuck Hastings
which is a good read, though I couldn't find it on the web.
The avalanche pulser described in the appendix to Linear
application note 79 might be what you
want.http://www.linear.com/pc/downloadDocument.do?navId=H0,C3,P1012,D4168


This app note and a few other app notes and web sites discuss making a
pulse generator with a 2N2369 transistor. It looks like they are
mostly referring to the TO-92 package instead of the surface mount. I
notice that the surface mount usually have a lower power dissipation,
but also would seem to have better RF characteristics due to the
shorter leads. Does anyone have any experience with surface mount vs.
TO-92 for avalanche pulse generation? While I don't like the idea of
soldering surface mount components, I'll do it if I have to.

Thanks
What little experience I do have confirmed the standard RF maxim
"long legs bad, short legs good". I have slightly more experience
with hand soldering surface mount transistors (and other two and three
legged components). Its not as difficult as it looks. After
a day or two you've got completely used to it.
 

Welcome to EDABoard.com

Sponsor

Back
Top