A quicker LM393 ?

[Eeyore]

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

Suggestions ?

Graham

 

[Martin Griffith]

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

Suggestions ?

Graham

I always have problems when I build a LM393 on strip board prototypes
with MHz oscs on the transistions. I've tried the usual positive
feedback tricks, etc

Is it just me?


Martin

 

[John Popelish]

I always have problems when I build a LM393 on strip board prototypes
with MHz oscs on the transistions. I've tried the usual positive
feedback tricks, etc

Is it just me?

It might be. ;-)

I generally have very good luck with plugboard prototypes
using the LM393.

John Popelish

 

[John Popelish]

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

Suggestions ?

The LM319 dual is not a drop in replacement, nor a similar
design with just higher speed. but it is faster.

http://cache.national.com/ds/LM/LM119.pdf

Though there are lots of variations on the 393, made by
various companies, like Linear Technology, many are slower,
with lower power consumption and work at lower voltage.
There may be something out there, faster but otherwise
similar, but it will be no where as commonly available or
cheap as the 393.

If something with different internal design might work, what
are your requirements?

 

[Martin Griffith]

It might be. ;-)

I generally have very good luck with plugboard prototypes
using the LM393.

John Popelish

<sigh>
I had better get a lower bandwidth scope then




Martin

 

[Winfield Hill]

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

Suggestions ?

Graham

The LMV393 may be slightly faster. I like TI's
cmos TLC3702 version, with active-pullup outputs.
Although it's officially slower than the LM393,
in some circuits with high-value pullup resistors
it might be faster. The TLV3702 is an attractive
nanopower version that's quite slow. Yawn...

 

[Tim Williams]

LM360 is blinding fast TTL. Single per package and gobs of current, so not
exactly just "a little" quicker.

LM319 as mentioned is about inbetween the 393 and 360. IIRC, the 319 comes
in single units as well.

Tim

 

[Winfield Hill]

The LMV393 may be slightly faster. I like TI's
cmos TLC3702 version, with active-pullup outputs.
Although it's officially slower than the LM393,
in some circuits with high-value pullup resistors
it might be faster. The TLV3702 is an attractive
nanopower version that's quite slow. Yawn...

Ah, I forgot about the max907, same pinout, but very
fast, almost 100x faster than the lm393. Sadly Maxim
has discontinued it: "This product was manufactured
for Maxim by an outside wafer foundry using a process
that is no longer available." But if you want to give
Maxim another chance, their max942 is about 5x faster
than the lm393 The max942 has an active pullup. The
miniDIP is $3.62 at Newark. Free samples from Maxim.

Or you might try TI's tlc372 and tlv2352 parts, they
are cheap and may be a bit faster than the lm393.

 

[Winfield Hill]

Ah, I forgot about the max907, same pinout, but very
fast, almost 100x faster than the lm393. Sadly Maxim
has discontinued it: "This product was manufactured
for Maxim by an outside wafer foundry using a process
that is no longer available." But if you want to give
Maxim another chance, their max942 is about 5x faster
than the lm393 The max942 has an active pullup. The
miniDIP is $3.62 at Newark. Free samples from Maxim.

Or you might try TI's tlc372 and tlv2352 parts, they
are cheap and may be a bit faster than the lm393.

Oh, one thing, most of these are low-voltage parts,
best used at 0/+5V, etc.; no +/-15V for these guys!

 

[John Larkin]

The LMV393 may be slightly faster. I like TI's
cmos TLC3702 version, with active-pullup outputs.
Although it's officially slower than the LM393,
in some circuits with high-value pullup resistors
it might be faster. The TLV3702 is an attractive
nanopower version that's quite slow. Yawn...

LVDS receivers are ns-speed comparators for around 50 cents. They do
tend to have built-in DC offsets.

John

 

[Eeyore]

I always have problems when I build a LM393 on strip board prototypes
with MHz oscs on the transistions. I've tried the usual positive
feedback tricks, etc

Is it just me?

Hard for me to say. The last time I used stripboard was 1990.

Graham

 

[Eeyore]

The LM319 dual is not a drop in replacement, nor a similar
design with just higher speed. but it is faster.

http://cache.national.com/ds/LM/LM119.pdf

A couple of hours after I posted this I remembered the 319. I had thought it was
of the same performance as the 393/339 but purely a single.

In fact it looks like it may be just the ticket.

It's for use in a switching PSU. It looks like 'rolling my own' is the best bet
for my simple low drop-out buck regulator.

Graham

 

[Martin Griffith]

Hard for me to say. The last time I used stripboard was 1990.

Graham

Just about to wire up a bit of stripboard that I managed to find, with
a 74HC221, a 74hc86 , lm393 and an AT89s4051 so that I can decode
smpte timecode played from a laptop. It's not worth waiting for a pcb
from Olimex


Martin

 

[Martin Griffith]

LVDS receivers are ns-speed comparators for around 50 cents. They do
tend to have built-in DC offsets.

John

Which LVDS parts do you use?

Thanks


Martin

 

[Eeyore]

Just about to wire up a bit of stripboard that I managed to find, with
a 74HC221, a 74hc86 , lm393 and an AT89s4051 so that I can decode
smpte timecode played from a laptop. It's not worth waiting for a pcb
from Olimex

Have you looked at pcb express ?

Graham

 

[Martin Griffith]

Have you looked at pcb express ?

Graham

Not recently, but Olimex is generally fine for me, this will be up
and programmed by tea time today, I only decided I needed it yesterday
afternoon, after a couple of mugs of rioja


Martin

 

[Eeyore]

Not recently, but Olimex is generally fine for me, this will be up
and programmed by tea time today, I only decided I needed it yesterday
afternoon, after a couple of mugs of rioja

Do you find Olimex a good prototype/small quantity production supplier ? What are their
turnaround times like ? Any info gladly received ! I'm looking for a decent supplier
right now. What CAD file formats do they support too ?

Graham

 

[Martin Griffith]

Do you find Olimex a good prototype/small quantity production supplier ? What are their
turnaround times like ? Any info gladly received ! I'm looking for a decent supplier
right now. What CAD file formats do they support too ?

Graham

check your email


Martin

 

[Eeyore]

check your email

Thanks.

Graham

 

[Eeyore]

Thanks.

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