A quicker LM393 ?

[Martin Griffith]

Oh crikey, just remembered ! A quasi-random unconnected thought. Ages back you
mentioned an outfit that had a compiler for the former 'Alesis' DSP chips.

I thought I'd bookmarked it but can't find it. Can you refresh my memory ?

Graham

wavefrontsemi
available from profusionplc.com
But the forum on wavefront has closed, and they no longer have Dice11
on the website.

seems a bit worrying


Martin

 

[Martin Griffith]

wavefrontsemi
available from profusionplc.com
But the forum on wavefront has closed, and they no longer have Dice11
on the website.

seems a bit worrying


Martin

oops, left the url out
http://www.axoris.be/VirtuAL3101.php



Martin

 

[John Larkin]

Which LVDS parts do you use?

Several of the National 5 volt and 3.3 volt parts, like DS90LV018 and
DS90C402.

The Fairchild FIN1101 is lvds-to-lvds and is blinding fast. It can be
handy if you treat it as an LVDS-output comparator. It's handy for
distributing fpga clocks, too.

Most LVDS-to-ttl converters will work fine with one input grounded,
even though that's not a legal common-mode voltage. You can make a
nice LC oscillator with a tank to ground and a little feedback.

John

 

[John Fields]

Looking for an inexpensive commodity dual comparator that's a little quicker
than the ubiquitous LM393.

Suggestions ?

 

[Joseph H Allen]

Looking for an inexpensive commodity dual comparator that's a little quicker
than the ubiquitous LM393.

Suggestions ?

Graham

Along the same lines as the LVDS receiver.. how about an RS-422 receiver
like an SN75173 or 26LS32? TTL outputs, -12V to 12V input range (even with
a single 5V supply), should work up to about 15 MHz. Low offset voltage?
Forget about it (in fact it has 50 mV of hysteresis), but perhaps it does
not matter for you.

 

[John Larkin]

What's this, the winner of one of those unreadable-C contests?

int
a[1817];main(z,p,q,r){for(p=80;q+p-80;p-=2*a[p])for(z=9;z--q=3&(r=time(0)
+r*57)/7,q=q?q-1?q-2?1-p%79?-1:0%79-77?1:0<1659?79:0>158?-79:0,q?!a[p+q*2
]?a[p+=a[p+=q]=q]=q:0:0;for(;q++-1817printf(q%79?"%c":"%c\n","
#"[!a[q-1]]);}


No wonder they call it "code"!

John

 

[Joseph H Allen]

Another option: AD8561 (an upgrade of LT1016), although it's a single, not a
dual. I've had great success using these as very low jitter video sync
separators in the past (for when an LM1881 just will not do).

What's this, the winner of one of those unreadable-C contests?

Compile it!

 

[Eeyore]

Another option: AD8561 (an upgrade of LT1016), although it's a single, not a
dual. I've had great success using these as very low jitter video sync
separators in the past (for when an LM1881 just will not do).

LT and AD ?

Sounds expensive to me.

Graham

 

[Spehro Pefhany]

On Mon, 19 Nov 2007 03:23:24 +0000 (UTC), the renowned

Another option: AD8561 (an upgrade of LT1016), although it's a single, not a
dual. I've had great success using these as very low jitter video sync
separators in the past (for when an LM1881 just will not do).



Compile it!

A puzzle within a puzzle. Cute.


Best regards,
Spehro Pefhany

 

[John Devereux]

Another option: AD8561 (an upgrade of LT1016), although it's a single, not a
dual. I've had great success using these as very low jitter video sync
separators in the past (for when an LM1881 just will not do).



Compile it!

/* [email protected] AB1GO */ /* Joseph H. Allen */
int a[1817];main(z,p,q,r){for(p=80;q+p-80;p-=2*a[p])for(z=9;z--q=3&(r=time(0)
+r*57)/7,q=q?q-1?q-2?1-p%79?-1:0%79-77?1:0<1659?79:0>158?-79:0,q?!a[p+q*2
]?a[p+=a[p+=q]=q]=q:0:0;for(;q++-1817printf(q%79?"%c":"%c\n"," #"[!a[q-1]]);}

--->

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############# ### # # # # ### # ### # # ####### # ### ####### # ####### # ### #
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# # # ### # ######### ##### ### # ### ### # # ### ####### ### ### ##### # # # #
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# # ####### ### # # ### # ##### ### # ####### # ### # # ##### # ### ### ### ###
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##### ##### # ### ##### ##### # ### # # # # # # ### # # ##### # ### ### ### ###
### # # # ### # # # # # # # # # # # #
###############################################################################



Reminds me of my 1-line BASIC program to plot a sine wave, on my UK101
kit computer - it only had 768 bytes of free RAM so that was about all
it could manage.

 

[Winfield]

LT and AD ?

Sounds expensive to me.

Graham

Let me mention again, in case you missed it, Maxim's
MAX942 is about 8x faster than the LM393, about 80ns
vs. 750/1250ns for 5mV overdrive. Same dual pinout,
inputs work to ground, etc. Note, it has active-pullup
outputs. Newark (Farnell) has the miniDIP package in
stock, $3.62 ea. Or get free samples from Maxim.

 

[Eeyore]

Let me mention again, in case you missed it, Maxim's
MAX942 is about 8x faster than the LM393, about 80ns
vs. 750/1250ns for 5mV overdrive. Same dual pinout,
inputs work to ground, etc. Note, it has active-pullup
outputs. Newark (Farnell) has the miniDIP package in
stock, $3.62 ea. Or get free samples from Maxim.

Thanks for that Win, but it looks to me like the LM319 fits the bill for just
29p @ 1 off from Farnell.

Inputs working to (and even just below) ground would have been nice. I'll need
to think around that.

Graham

 

[Winfield Hill]

Thanks for that Win, but it looks to me like the LM319 fits the bill for just
29p @ 1 off from Farnell.

Inputs working to (and even just below) ground would have been nice. I'll need
to think around that.

Graham

Oh, I assumed you needed the same package size
and pinout as the LM393. There are all kinds of
possibilities if you give up that requirement.

 

[Eeyore]

Oh, I assumed you needed the same package size
and pinout as the LM393.

Just the same function. It's not a retrofit so allcomers are welcome.

Graham

 

[Paul Burke]

Let me mention again, in case you missed it, Maxim's
MAX942 is about 8x faster than the LM393, about 80ns
vs. 750/1250ns for 5mV overdrive. Same dual pinout,
inputs work to ground, etc. Note, it has active-pullup
outputs. Newark (Farnell) has the miniDIP package in
stock, $3.62 ea. Or get free samples from Maxim.

It also oscillates at the slightest provocation, so your layout
(especially lengths of input tracks) will have to be spot on. I fell
over this badly once- the more so because the prototype I tested it on
behaved perfectly, it was only the production units that wobbled.