A quicker LM393 ?

oops, left the url out

Martin

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

--
LT1018

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.

--
/*  jhallen@world.std.com 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:p%79-77?1:0:p158?-79:0,q?!a[p+q*2
]?a[p+=a[p+=q]=q]=q:0:0;for(;q++-1817;)printf(q%79?"%c":"%c\n"," #"[!a[q-1]]);}

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:p%79-77?1:0:p158?-79:0,q?!a[p+q*2 ]?a[p+=a[p+=q]=q]=q:0:0;for(;q++-1817;)printf(q%79?"%c":"%c\n"," #"[!a[q-1]]);}

No wonder they call it "code"!

John

Compile it! :-)

--
/*  jhallen@world.std.com 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:p%79-77?1:0:p158?-79:0,q?!a[p+q*2
]?a[p+=a[p+=q]=q]=q:0:0;for(;q++-1817;)printf(q%79?"%c":"%c\n"," #"[!a[q-1]]);}

LT and AD ?

Sounds expensive to me.

Graham

A puzzle within a puzzle. Cute.

Best regards, Spehro Pefhany

--
"it's the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

/* snipped-for-privacy@world.std.com 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:p%79-77?1:0:p158?-79:0,q?!a[p+q*2 ]?a[p+=a[p+=q]=q]=q:0:0;for(;q++-1817;)printf(q%79?"%c":"%c\n"," #"[!a[q-1]]);}

--->

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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.

--

John Devereux

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

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.

need

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

Graham

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.