Are buffers ( CMOS 4050 etc) any use to protect the stamp''s outputs???
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Posts: 46,084
Hi Jon
So all I would need to do to protect my stamp from excessive current
sourcing would be to add 220 Ohm resistors in series? Can I then
connect a ULN2803 or should I leave out the 220 Ohm if I am
connecting it? Also what is the maximum current a 2803 would source
from the stamp to drive its maximum 500 milli amp Load? I have been
unable to work this out.
Many thanks
Arridh
--- In basicstamps@yahoogroups.com, "Jon Williams" <jwilliams@p...>
wrote:
> If you're simply looking to protect your Stamp you can put 220 ohm
> resistors in series with your outputs; we do this on the Homework
Board
> (BS2) and BS1 Project Board -- both boards are designed for
students.
> You may want to consider buffers if you need more current than the
Stamp
> can safely sink or source.
>
> -- Jon Williams
> -- Applications Engineer, Parallax
> -- Dallas Office
>
>
>
Original Message
> From: arridh_shashank [noparse][[/noparse]mailto:arridh_shashank@y...]
> Sent: Monday, December 29, 2003 1:36 AM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Are buffers ( CMOS 4050 etc) any use to
protect
> the stamp's outputs???
>
>
> Hey
>
> I'm not sure my self if this will work or not so I thought I'd ask
> you guys [noparse]:D[/noparse]. I wanted to protect my stamp outputs from gettin
> damaged by sourcing and sinking too much current so I looked
around
> and found the cmos 4050 chip non inverting hex buffer. I was
> wondering if it will protect my stamp from sourcing and sinking a
> lot of current. What I plan to do is to use it as a intermediate
> between my stamp and my output device so as to protect the stamp.
> Would this be a benifitial setup to have and is this the use the
> chip was developed for? Furthermore will it protect my stamp from
> damage in the instance that a large base current was drawn by a
> transistor or similar instance? Any light you guys can shed on the
> subject would be helpful.
>
> Many thanks
> Arridh
>
>
>
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So all I would need to do to protect my stamp from excessive current
sourcing would be to add 220 Ohm resistors in series? Can I then
connect a ULN2803 or should I leave out the 220 Ohm if I am
connecting it? Also what is the maximum current a 2803 would source
from the stamp to drive its maximum 500 milli amp Load? I have been
unable to work this out.
Many thanks
Arridh
--- In basicstamps@yahoogroups.com, "Jon Williams" <jwilliams@p...>
wrote:
> If you're simply looking to protect your Stamp you can put 220 ohm
> resistors in series with your outputs; we do this on the Homework
Board
> (BS2) and BS1 Project Board -- both boards are designed for
students.
> You may want to consider buffers if you need more current than the
Stamp
> can safely sink or source.
>
> -- Jon Williams
> -- Applications Engineer, Parallax
> -- Dallas Office
>
>
>
Original Message
> From: arridh_shashank [noparse][[/noparse]mailto:arridh_shashank@y...]
> Sent: Monday, December 29, 2003 1:36 AM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Are buffers ( CMOS 4050 etc) any use to
protect
> the stamp's outputs???
>
>
> Hey
>
> I'm not sure my self if this will work or not so I thought I'd ask
> you guys [noparse]:D[/noparse]. I wanted to protect my stamp outputs from gettin
> damaged by sourcing and sinking too much current so I looked
around
> and found the cmos 4050 chip non inverting hex buffer. I was
> wondering if it will protect my stamp from sourcing and sinking a
> lot of current. What I plan to do is to use it as a intermediate
> between my stamp and my output device so as to protect the stamp.
> Would this be a benifitial setup to have and is this the use the
> chip was developed for? Furthermore will it protect my stamp from
> damage in the instance that a large base current was drawn by a
> transistor or similar instance? Any light you guys can shed on the
> subject would be helpful.
>
> Many thanks
> Arridh
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the
Subject
> and Body of the message will be ignored.
>
>
> Yahoo! Groups Links
>
> To visit your group on the web, go to:
> http://groups.yahoo.com/group/basicstamps/
>
> To unsubscribe from this group, send an email to:
> basicstamps-unsubscribe@yahoogroups.com
>
> Your use of Yahoo! Groups is subject to:
> http://docs.yahoo.com/info/terms/
>
>
>
>
> This message has been scanned by WebShield. Please report SPAM to
> abuse@p...