Searching \ for '[EE]: "5V tolerant" 3V buffer?' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/index.htm?key=tolerant+buffer
Search entire site for: '"5V tolerant" 3V buffer?'.

Exact match. Not showing close matches.
PICList Thread
'[EE]: "5V tolerant" 3V buffer?'
2002\08\26@010102 by Harold Hallikainen

picon face
I need to convert a couple 5V logic lines out of a PIC running on 5V to 3V levels to drive a MultiMedia card. I've seen some 3V PLDs that have "5V tolerant" inputs. Does anyone know of a simple buffer like that? One that I'd be able to power with my 3V supply, but drive the inputs with 0V and 5V?

Thanks!

Harold




________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today!  For your FREE software, visit:
dl.http://www.juno.com/get/web/.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2002\08\26@011136 by smail B - CTD, Chennai.

flavicon
face
Hi,

Just have a look at 74LVC244. If you need more pin count go for 74LVC16244.
These buffers have +5V tolerant I/Os. Further, It should be noted that prop
delay varies with supply voltage.

Hope this helps,

...Ismail



{Original Message removed}

2002\08\26@012214 by Charles Craft

picon face
Did a quick Yahoo search with "5v 3v inputs" and "5v 3v inputs divider"


Article on using driver chips:
http://www.philipslogic.com/support/appnotes/an240.pdf


Why won't a resistor voltage divider work:
http://www.icst.com/products/pdf/an06.pdf





{Original Message removed}

2002\08\26@141301 by Peter L. Peres

picon face
On Mon, 26 Aug 2002, Harold Hallikainen wrote:

>I need to convert a couple 5V logic lines out of a PIC running on 5V to
>3V levels to drive a MultiMedia card. I've seen some 3V PLDs that have
>"5V tolerant" inputs. Does anyone know of a simple buffer like that? One
>that I'd be able to power with my 3V supply, but drive the inputs with 0V
>and 5V?

If you do not use very fast outputs series resistors and fast zeners
(tranzorbs or the clamp circuit I showed with a small mod) are all you
need. 3V Voh from the MMC is within the permissible range for Vih on PIC
inputs (unless it is a schmitt input).

Peter

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2002\08\26@142707 by James.Hyslop

flavicon
face
Check out
http://www.chipcenter.com/embapps/e018fig1.htm;$sessionid$RNLARRYAABGHCQSNDI
SSFEQ for a simple voltage shifter.  Also you might want to check out
Amtel's dataflash memory, which is available in a MMC package, which has 5V
tolerant pins.

James Hyslop



{Original Message removed}

2002\08\27@045412 by Roman Black

flavicon
face
Peter L. Peres wrote:
>
> On Mon, 26 Aug 2002, Harold Hallikainen wrote:
>
> >I need to convert a couple 5V logic lines out of a PIC running on 5V to
> >3V levels to drive a MultiMedia card. I've seen some 3V PLDs that have
> >"5V tolerant" inputs. Does anyone know of a simple buffer like that? One
> >that I'd be able to power with my 3V supply, but drive the inputs with 0V
> >and 5V?
>
> If you do not use very fast outputs series resistors and fast zeners
> (tranzorbs or the clamp circuit I showed with a small mod) are all you
> need. 3V Voh from the MMC is within the permissible range for Vih on PIC
> inputs (unless it is a schmitt input).


Better to use 2 resistors, voltage divider style.
With values of 1k and 1.5k it will perform well at
PIC output speeds, better than a zener solution.

Like the zener solution it WILL allow bidirectional
comms (3v -> 5v) as long as the PIC input is TTL
type as Peter mentioned.
-Roman

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2002\08\27@045421 by mike

flavicon
face
Fairchild do a tiny logic series of surface mount buffers that have 5v
tolerant inputs whwn running on lower voltages.
Try the NC7SZ125 for example.

Best Regards,

Mike.

{Original Message removed}

2002\08\27@102956 by Harold Hallikainen

picon face
Thanks to all those who responded. Since we need to convert 3 lines from 5V down to 3.3V, we went with the Fairchild Tiny Logic triple buffer. I note that TI also has a similar part.

Again, thanks to all!

Harold




________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today!  For your FREE software, visit:
dl.http://www.juno.com/get/web/.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2002\08\27@173655 by miked

flavicon
face
You might check out Maxim's MAX3372-8 and MAX3390-93
>
> I need to convert a couple 5V logic lines out of a PIC running on 5V to 3V
> levels to drive a MultiMedia card. I've seen some 3V PLDs that have "5V
> tolerant" inputs. Does anyone know of a simple buffer like that? One that
> I'd be able to power with my 3V supply, but drive the inputs with 0V and
> 5V?

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


More... (looser matching)
- Last day of these posts
- In 2002 , 2003 only
- Today
- New search...