TTL signal

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jamie_...@yahoo.com

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Dec 9, 2008, 3:11:09 PM12/9/08
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I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
TTL signal.

Phil Hobbs

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Dec 9, 2008, 3:14:05 PM12/9/08
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jamie_...@yahoo.com wrote:
> I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
> TTL signal.

What sort of TTL are you going to use with a 3 ns pulse????

Cheers,

Phil Hobbs

BobW

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Dec 9, 2008, 3:18:46 PM12/9/08
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"Phil Hobbs" <pcdhSpamM...@electrooptical.net> wrote in message
news:493ED18D...@electrooptical.net...

One that stays solidly at either a high or low level?

Bob
--
== All google group posts are automatically deleted due to spam ==


jamie_...@yahoo.com

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Dec 9, 2008, 3:20:59 PM12/9/08
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On Dec 9, 3:14 pm, Phil Hobbs <pcdhSpamMeSensel...@electrooptical.net>
wrote:

I'm looking to use the TTL as a trigger pulse for an NI scope
application. So the pulse can be stretched longer than the 3nS pulse.
The 3-5nS pulse is coming from a photodiode circuit on a Cobolt Tango
Laser.

jamie_...@yahoo.com

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Dec 9, 2008, 3:22:59 PM12/9/08
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On Dec 9, 3:18 pm, "BobW" <nimby_GIMME_SOME_S...@roadrunner.com>
wrote:
> "Phil Hobbs" <pcdhSpamMeSensel...@electrooptical.net> wrote in message
>
> news:493ED18D...@electrooptical.net...

>
> > jamie_krie...@yahoo.com wrote:
> >> I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
> >> TTL signal.
>
> > What sort of TTL are you going to use with a 3 ns pulse????
>
> > Cheers,
>
> > Phil Hobbs
>
> One that stays solidly at either a high or low level?
>
> Bob
> --
> == All google group posts are automatically deleted due to spam ==

It does not have to stay high or low, except sufficiently to be used
as a trigger for NI scope input.

Jim Thompson

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Dec 9, 2008, 3:30:38 PM12/9/08
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On Tue, 9 Dec 2008 12:18:46 -0800, "BobW"
<nimby_GIMM...@roadrunner.com> wrote:

>
>"Phil Hobbs" <pcdhSpamM...@electrooptical.net> wrote in message
>news:493ED18D...@electrooptical.net...
>> jamie_...@yahoo.com wrote:
>>> I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
>>> TTL signal.
>>
>> What sort of TTL are you going to use with a 3 ns pulse????
>>
>> Cheers,
>>
>> Phil Hobbs
>
>One that stays solidly at either a high or low level?
>
>Bob

Sno-o-o-o-o-ort ;-)

...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 http://www.analog-innovations.com | 1962 |

I love to cook with wine Sometimes I even put it in the food

Tim Shoppa

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Dec 9, 2008, 3:32:33 PM12/9/08
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On Dec 9, 3:11 pm, jamie_krie...@yahoo.com wrote:
> I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
> TTL signal.

LVDS receivers make nice comparators with "CMOS"/"TTL" outputs at
these input voltage levels.

e.g. DS90C032 et al for few hundred mV swing inputs.

If the input isn't actually differential then appropriately biasing
the inactive input does the trick.

Sometimes the same parts used to be known as LVPECL receivers.

Tim.

Spehro Pefhany

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Dec 9, 2008, 3:35:36 PM12/9/08
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On Tue, 9 Dec 2008 12:11:09 -0800 (PST), jamie_...@yahoo.com
wrote:

>I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
>TTL signal.

That's a bit on the fast side for a TTL-level output, but you can try
looking at fast comparators. LVDS (or PECL or CML) will be easier.

Tim Wescott

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Dec 9, 2008, 4:05:21 PM12/9/08
to

You should probably think in terms that the pulse _must be_ stretched,
not "could be". Check the documentation on your hardware.

I assume that you're looking for a circuit? Your question didn't make
it clear.

Perhaps you should start over again and tell the _whole_ story: "I am
trying to trigger a NI scope board (which one?) with a Cobolt Tango
laser which has a photodiode output. The NI board needs a TTL-level
input, but the laser pulse is 3-5ns long and only 150mV high".
Something like that.

Then you'll have provided a much nicer framework for folks to answer
your need.

You may want to make clear your requirements for jitter and maximum
pulse width -- if you have to slow it down for TTL you can pretty much
guarantee that you'll introduce jitter in the process, or the receiving
board will.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html

PeterD

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Dec 9, 2008, 4:09:13 PM12/9/08
to


Uh, really, really, really fast TTL?

John Larkin

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Dec 9, 2008, 5:15:11 PM12/9/08
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On Tue, 9 Dec 2008 12:20:59 -0800 (PST), jamie_...@yahoo.com
wrote:

I assume the scope has an analog trigger input, with programmable
trigger level. So maybe all you need is a linear amplifier.

Like this, maybe:

http://www.minicircuits.com/pdfs/ZX60-6013E+.pdf

This is likly a single MMIC in a can, so probably inverts the signal.


If the scope really needs TTL, of course we could sell you one of
these...

http://www.highlandtechnology.com/DSS/T860DS.html


John


Jamie

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Dec 9, 2008, 8:06:03 PM12/9/08
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jamie_...@yahoo.com wrote:

> I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
> TTL signal.

You have not specified if there is a DC component in this signal?

It would make a world of difference in design to know this.

From what I can gather in your info, it's 0..150v but it may
actually be a 10 to 10.150V PK, for example.
etc..

http://webpages.charter.net/jamie_5"

Rich Grise

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Dec 9, 2008, 8:28:55 PM12/9/08
to
On Tue, 09 Dec 2008 15:14:05 -0500, Phil Hobbs wrote:
> jamie_...@yahoo.com wrote:
>> I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
>> TTL signal.
>
> What sort of TTL are you going to use with a 3 ns pulse????
>
The one in the textbook?

Cheers!
Rich

Rich Grise

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Dec 9, 2008, 8:30:55 PM12/9/08
to
On Tue, 09 Dec 2008 13:05:21 -0800, Tim Wescott wrote:
> jamie_...@yahoo.com wrote:
>> On Dec 9, 3:14 pm, Phil Hobbs <pcdhSpamMeSensel...@electrooptical.net>
>> wrote:
>>> jamie_krie...@yahoo.com wrote:
>>>> I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
>>>> TTL signal.
>>> What sort of TTL are you going to use with a 3 ns pulse????
>>
>> I'm looking to use the TTL as a trigger pulse for an NI scope
>> application. So the pulse can be stretched longer than the 3nS pulse.
>> The 3-5nS pulse is coming from a photodiode circuit on a Cobolt Tango
>> Laser.
>
> You should probably think in terms that the pulse _must be_ stretched, not
> "could be". Check the documentation on your hardware.
>
> I assume that you're looking for a circuit? Your question didn't make it
> clear.
>
> Perhaps you should start over again and tell the _whole_ story: "I am
> trying to trigger a NI scope board (which one?) with a Cobolt Tango laser
> which has a photodiode output. The NI board needs a TTL-level input, but
> the laser pulse is 3-5ns long and only 150mV high". Something like that.
>
> Then you'll have provided a much nicer framework for folks to answer your
> need.

Googlies don't know how to do that. If they did, they'd get their own
answers. This is just copied out of the exam.

Cheers!
Rich

Rich Grise

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Dec 9, 2008, 8:31:49 PM12/9/08
to
On Tue, 09 Dec 2008 16:09:13 -0500, PeterD wrote:
> On Tue, 09 Dec 2008 15:14:05 -0500, Phil Hobbs
> <pcdhSpamM...@electrooptical.net> wrote:
>
>>jamie_...@yahoo.com wrote:
>>> I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
>>> TTL signal.
>>
>>What sort of TTL are you going to use with a 3 ns pulse????
>
> Uh, really, really, really fast TTL?

Upside-down ECL? ;-)

Cheers!
Rich

Jamie

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Dec 9, 2008, 8:51:24 PM12/9/08
to
Rich Grise wrote:

I like the left handed one's my self!


http://webpages.charter.net/jamie_5"

Robert Baer

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Dec 9, 2008, 11:22:40 PM12/9/08
to
Phil Hobbs wrote:

Maybe he should go back and use gold enhanced RTL logic??

bill....@ieee.org

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Dec 10, 2008, 5:35:20 PM12/10/08
to

I worked up a pulse-stretcher for pretty much exactly this application

Ghiggino, K.P., Phillips, D., and Sloman, A.W. "Nanosecond pulse
stretcher",Journal of Physics E: Scientific Instruments, 12, 686-687
(1979).

It used a pair of 5GHZ wideband transistors to make a Schmitt trigger
- these days I'd probably use BFR92 npn parts rather than the pnp
parts we used back then.

It worked. It could have been improved, but since it did the job
nobody was interested in going to the trouble of designing something
better.

--
Bill Sloman, Nijmegen

John Larkin

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Dec 17, 2008, 11:12:15 PM12/17/08
to


Hey, it works!

ftp://66.117.156.8/3ns_TTL.jpg

That's a 3 ns, 100 mV input and 4 volts out. It even works with an 80
mV, 1 ns input, still 4 volts out. I'm sort of impressed!

John

Phil Hobbs

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Dec 18, 2008, 9:05:19 AM12/18/08
to

I just built one of those amps into a 6 GHz microwave setup yesterday.
16 dB gain at 1 GHz, 12 dB at 6 GHz, $50 with nice gold-plated SMA
connectors. Not bad.

BTW John, could you set up your FTP server to accept PASV? I have to
download those pictures using command-line FTP and look at them in a
photo editor, because Mozilla browsers always want to use passive-mode FTP.

Cheers,

Phil Hobbs

John Larkin

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Dec 18, 2008, 10:27:22 AM12/18/08
to

Sorry, I have no idea what those words mean. My little ISP, a few guys
in a storefront in Berkeley, host it for me for free, and I've had
plenty enough trouble getting it to work at all. Firefox seems happy
opening the pics as-is. I assume it has a name, and not just an IP
address, but I can't figure out what it is.

John

Nobody

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Dec 18, 2008, 11:01:30 AM12/18/08
to
On Thu, 18 Dec 2008 07:27:22 -0800, John Larkin wrote:

>>> ftp://66.117.156.8/3ns_TTL.jpg

>>BTW John, could you set up your FTP server to accept PASV? I have to
>>download those pictures using command-line FTP and look at them in a
>>photo editor, because Mozilla browsers always want to use passive-mode FTP.
>>
>
> Sorry, I have no idea what those words mean.

FTP uses two TCP connections: a control channel and a data channel. The
control channel is used for sending commands and receiving status
responses. The data channel is used for sending and receiving data (files,
and directory listings).

The control channel is established by the client connecting to the server.
In the original FTP implementation, the data channel was established by
the server connecting back to the client (i.e. the client is the "server"
end of the data connection).

This doesn't work with some firewalls, which block inbound connections
unless specifically told otherwise. Passive (PASV) mode is an extension to
the FTP protocol which allows the data channel to be established by the
client connecting to the server.

> My little ISP, a few guys
> in a storefront in Berkeley, host it for me for free, and I've had
> plenty enough trouble getting it to work at all. Firefox seems happy
> opening the pics as-is.

It works for me, but that may just be that my firewall is more lenient
than Phil's. Some firewalls have explicit support for (non-passive) FTP.
They recognise FTP control channels (port 21), and monitor the traffic.
When the client tells the server to connect back to it on a specific port,
they add a temporary "exemption" to allow the FTP server to connect to
that port.

> I assume it has a name, and not just an IP
> address, but I can't figure out what it is.

ftp://jjlarkin.lmi.net/3ns_TTL.jpg

Jan Panteltje

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Dec 18, 2008, 11:17:50 AM12/18/08
to
On a sunny day (Thu, 18 Dec 2008 07:27:22 -0800) it happened John Larkin
<jjla...@highNOTlandTHIStechnologyPART.com> wrote in
<ghqkk4hqakgst5nbm...@4ax.com>:

> I assume it has a name, and not just an IP
>address, but I can't figure out what it is.


That is very simple:
grml: ~ # host 66.117.156.8
8.156.117.66.in-addr.arpa domain name pointer jjlarkin.lmi.net.

So, in your browser type:
ftp://jjlarkin.lmi.net/3ns_TTL.jpg

Phil Hobbs

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Dec 18, 2008, 11:43:18 AM12/18/08
to
John Larkin wrote:
> Sorry, I have no idea what those words mean. My little ISP, a few guys
> in a storefront in Berkeley, host it for me for free, and I've had
> plenty enough trouble getting it to work at all. Firefox seems happy
> opening the pics as-is. I assume it has a name, and not just an IP
> address, but I can't figure out what it is.
>
> John
>

Hmm. Maybe it's a firewall issue then. In any case, I can help with
the second problem:

I:\>nslookup 66.117.156.8
Server: yktns1.watson.ibm.com
Address: 9.2.250.86

Name: jjlarkin.lmi.net
Address: 66.117.156.8


Cheers,

Phil Hobbs

Jim Thompson

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Dec 18, 2008, 11:52:04 AM12/18/08
to

"Name Server Lookup" in NetScanTools v4.02

John Larkin

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Dec 18, 2008, 12:00:57 PM12/18/08
to
On Thu, 18 Dec 2008 16:01:30 +0000, Nobody <nob...@nowhere.com> wrote:


>
>> I assume it has a name, and not just an IP
>> address, but I can't figure out what it is.
>
> ftp://jjlarkin.lmi.net/3ns_TTL.jpg

Cool. Thanks.

John

John Larkin

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Dec 18, 2008, 12:06:12 PM12/18/08
to

Neat. I don't consider all this protcol/path/port sort of stuff to be
"electronics", and I haven't bothered to understand much of it... just
enough to get my Ethernet instruments to talk. There's plenty of real
stuff to keep up with.

I'll ping my guys at LMI and see if they can turn on the PASV thing
without breaking something else. Which they usually do.

John

Rich Grise

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Dec 18, 2008, 1:59:41 PM12/18/08
to
On Thu, 18 Dec 2008 07:27:22 -0800, John Larkin wrote:
> On Thu, 18 Dec 2008 09:05:19 -0500, Phil Hobbs
>>
>>BTW John, could you set up your FTP server to accept PASV? I have to
>>download those pictures using command-line FTP and look at them in a
>>photo editor, because Mozilla browsers always want to use passive-mode
>>FTP.
>>
> Sorry, I have no idea what those words mean. My little ISP, a few guys in
> a storefront in Berkeley, host it for me for free, and I've had plenty
> enough trouble getting it to work at all. Firefox seems happy opening the
> pics as-is. I assume it has a name, and not just an IP address, but I
> can't figure out what it is.

$ whois 66.117.156.8

OrgName: LanMinds, Inc.
OrgID: LANM
Address: 1700 Martin Luther King Jr. Way
City: Berkeley
StateProv: CA
PostalCode: 94709
Country: US

NetRange: 66.117.128.0 - 66.117.159.255
CIDR: 66.117.128.0/19
NetName: LOCRIAN-ENTERPRISES
NetHandle: NET-66-117-128-0-1
Parent: NET-66-0-0-0-0
NetType: Direct Allocation
NameServer: NS2.LMI.NET
NameServer: NS3.LMI.NET
Comment:
RegDate: 2002-10-09
Updated: 2005-03-07

OrgAbuseHandle: ABUSE37-ARIN
OrgAbuseName: Abuse
OrgAbusePhone: +1-510-843-6389
OrgAbuseEmail: ab...@lmi.net

OrgNOCHandle: NOC140-ARIN
OrgNOCName: Network Operations Center
OrgNOCPhone: +1-510-843-6389
OrgNOCEmail: n...@lmi.net

OrgTechHandle: NOC140-ARIN
OrgTechName: Network Operations Center
OrgTechPhone: +1-510-843-6389
OrgTechEmail: n...@lmi.net

OrgTechHandle: GM41-ARIN
OrgTechName: Morrell, Gary
OrgTechPhone: +1-510-843-6389
OrgTechEmail: ga...@lmi.net

# ARIN WHOIS database, last updated 2008-12-17 19:10
# Enter ? for additional hints on searching ARIN's WHOIS database.

Cheers!
Rich

John Larkin

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Dec 18, 2008, 5:00:08 PM12/18/08
to
On Thu, 18 Dec 2008 09:05:19 -0500, Phil Hobbs
<pcdhSpamM...@electrooptical.net> wrote:

Hi, Phil,

I asked my ISP guys to enable PASV, and they replied that PASV is the
responsibility of the client, not the server, and they demonstrated
that they could access my site in PASV mode. They say...

"PASV or passive mode is a setting in the ftp client not on the
server. Some web browser's ftp clients are severely broken -cough-
Internet Exploder -cough. They might need to use a stand alone ftp
client."


Hey, I tried.

John

Phil Hobbs

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Dec 18, 2008, 5:32:28 PM12/18/08
to
John,

Thanks. My FTP server has settings to enable/disable both active and
passive FTP. If it's switched on at their end, it's probably a firewall
issue.

Cheers,

Phil Hobbs

Jasen Betts

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Dec 20, 2008, 8:59:37 PM12/20/08
to
On 2008-12-18, Phil Hobbs <pcdhSpamM...@electrooptical.net> wrote:
> John Larkin wrote:
>> On Thu, 18 Dec 2008 09:05:19 -0500, Phil Hobbs
>> <pcdhSpamM...@electrooptical.net> wrote:
>>>
>>> BTW John, could you set up your FTP server to accept PASV? I have to
>>> download those pictures using command-line FTP and look at them in a
>>> photo editor, because Mozilla browsers always want to use passive-mode FTP.
>>>
>>> Cheers,

PASV seems to be enabled now.

jasen@gonzo:~$ ftp 66.117.156.8
Connected to 66.117.156.8.
220 jjlarkin.lmi.net FTP server (Version wu-2.6.2(1) Wed Dec 5
16:35:31 PST 2001) ready.
Name (66.117.156.8:jasen): ftp
331 Guest login ok, send your complete e-mail address as password.
Password:
230 Guest login ok, access restrictions apply.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> passive
Passive mode on.
ftp>

Also I don't recall ever having a problem using seamonkey to view his files.

OTOH I can't get to jamie6" 's web site, my ISP is blocking traffic to
that ip-address block and gives me some line of bullshit when I ask them
about it.

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