Can the stamp handle 9V?
Archiver
Posts: 46,084
I really want to know if the stamp can handle 9v volts directly. The
board only gives it 5v but i want to put it on a board of my own. So
can I connect a 9v battery to the Vdd pin of the chip to run it?
board only gives it 5v but i want to put it on a board of my own. So
can I connect a 9v battery to the Vdd pin of the chip to run it?
Comments
[noparse][[/noparse]Non-text portions of this message have been removed]
But to be serious, no. the chips want 5 volts - put a regulator (e.g.
78L05) on the board. You can use a low-dropout regulator that will allow
the 9v battery to go down to less than 6 volts before it drops out of
regulation. The low dropout voltage means you can get the last drop of
juice out of the 9V battery, although once the voltage starts to drop, it
will probably go down fairly rapidly. The LM2396-5.0 from National is
cheap. At 10 ma load current, the chip only uses 0.2 ma itself, so it won't
add much drain to the 9V battery.
Larry
At 04:56 PM 12/9/2002 +0000, you wrote:
>I really want to know if the stamp can handle 9v volts directly. The
>board only gives it 5v but i want to put it on a board of my own. So
>can I connect a 9v battery to the Vdd pin of the chip to run it?
>
>
>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.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Larry Bradley
Orleans (Ottawa), Ontario, CANADA
good for 50 MAh. Be sure you "DO NOT" connect anything above +5 V to pin 21.
Pin 21 is for regulated +5v input OR it can be used for stamp regulated +5v
output. Do not draw more then the 50MAH maximum onboard stamp regulator.
At 05:19 PM 12/9/02 -0000, you wrote:
>What about voltage division ?
>
>
>
>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.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
Happy Holidays: Visit my Christmas webpage at
http://mntnweb.com/xmas.htm
Very respectfully, your obedient servant.
Kerry
Admin@M...
WWW server hosting [url=Http://mntnweb.com]Http://mntnweb.com[/url]
Kerry Barlow
p.o. box 21
kirkwood ny
13795
607-775-1575
Use a 5 volt regulator, they are inexpensive.
If you use voltage division, the current in the divider network should be
about 10 times greater than the current consumed by the circuit and that
wastes power. (the 10 times greater is just a general rule of thumb)
Also, when you use voltage division, if the 9v starts to drop and it will,
the 5 volts you didvided down will drop.
[noparse][[/noparse]Non-text portions of this message have been removed]
onboard regulator will then produce 5V from the 9V, power the Stamp, and
leave a little left over on the Vdd pin for you to use with other
circuts (but don't draw too much -- see the Stamp manual).
Al Williams
AWC
* 8 channels of PWM
http://www.al-williams.com/awce/pak5.htm
>
Original Message
> From: businesscc <businesscc@y...> [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=DmyKMXg26OKkFui_RhSbNqRSknCvka3y6cRO60PsKJTIR2meBO4M-lLAKlqA9WE751SMsuTXn3M_vobLIUd-]businesscc@y...[/url
> Sent: Monday, December 09, 2002 10:57 AM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]JUNK] [noparse][[/noparse]basicstamps] Can the stamp handle 9V?
>
>
> I really want to know if the stamp can handle 9v volts directly. The
> board only gives it 5v but i want to put it on a board of my own. So
> can I connect a 9v battery to the Vdd pin of the chip to run it?
>
>
> 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.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
>