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ac adapter

ArchiverArchiver Posts: 46,084
edited 2003-03-24 03:20 in General Discussion
hi, I've been using a 9v battery to power my basic stamp but now I
found an old ac adapter in my basement which outputs 9v DC at 300mA,
would that be ok for the basic stamp 2sx?

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 00:32
    In a message dated 03/22/2003 19:31:27 Eastern Standard Time,
    hard-on@t... writes:


    > hi, I've been using a 9v battery to power my basic stamp but now I
    > found an old ac adapter in my basement which outputs 9v DC at 300mA,
    > would that be ok for the basic stamp 2sx?
    >
    >

    Pretty marginal. You should have at least 500ma.

    Sid


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 00:37
    --- In basicstamps@yahoogroups.com, Newzed@a... wrote:
    > In a message dated 03/22/2003 19:31:27 Eastern Standard Time,
    > hard-on@t... writes:
    >
    >
    > > hi, I've been using a 9v battery to power my basic stamp but now
    I
    > > found an old ac adapter in my basement which outputs 9v DC at
    300mA,
    > > would that be ok for the basic stamp 2sx?
    > >
    > >
    >
    > Pretty marginal. You should have at least 500ma.
    >
    > Sid
    >
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]

    this website mentions only 60mA needed under 'current requirements':
    http://www.warburtech.com/Basic%20Stamps/BS2SX-IC/BS2SX-IC.htm

    I was just worried that 300mA would be too much....
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 00:43
    In a message dated 03/22/2003 19:38:26 Eastern Standard Time,
    hard-on@t... writes:


    > I was just worried that 300mA would be too much....
    >

    You could have 3000ma and it would matter. The Stamp only takes what it
    needs. The 300ma only indicates the capacity of the adapter.

    Sid


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 00:46
    In a message dated 03/22/2003 19:44:00 Eastern Standard Time, Newzed@a...
    writes:


    > You could have 3000ma and it would matter. The Stamp only takes what it
    > needs. The 300ma only indicates the capacity of the adapter.
    >
    >

    Type. Should have said " it wouldn't matter". Sorry

    Sid


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 00:50
    --- In basicstamps@yahoogroups.com, Newzed@a... wrote:
    > In a message dated 03/22/2003 19:44:00 Eastern Standard Time,
    Newzed@a...
    > writes:
    >
    >
    > > You could have 3000ma and it would matter. The Stamp only takes
    what it
    > > needs. The 300ma only indicates the capacity of the adapter.
    > >
    > >
    >
    > Type. Should have said " it wouldn't matter". Sorry
    >
    > Sid
    >
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]

    the fact that the mA written on the adapter represents a capacity and
    not an actual output makes plenty of sense...Duh. Thanks a lot, saved
    me from making another expensive radio shack purchase, I'm running
    out of money.
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 00:58
    In a message dated 3/22/2003 4:31:28 PM Pacific Standard Time,
    hard-on@t... writes:

    >
    > hi, I've been using a 9v battery to power my basic stamp but now I
    > found an old ac adapter in my basement which outputs 9v DC at 300mA,
    > would that be ok for the basic stamp 2sx?

    Yes if it is a somewhat clean source. It won't hurt anything to plug it in
    and try it. If it will not run on your 9v AC adaptor, verify that the input
    to the stamp is above 7 volts. If the input is above 7 volts and it will not
    run your stamp, but a 9v battery will run the stamp, I suspect the DC source
    from your AC adapter is "dirty."

    Ken


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 00:58
    Only the voltage matters when it comes to "oversized" adapters. If you apply
    5 volts to the stamp it'll take the same amount of juice whether your
    adapter capacity is 300 milliamp or 300 amp. Remember, current is determined
    by voltage and resistance (V=I/R). Since the resistance of your stamp is
    fixed, only raising the voltage can (and will) really hurt it.


    My 'lectronic Newb site http://members.shaw.ca/pmeloy/
    Original Message
    From: "Sam" <hard-on@t...>
    To: <basicstamps@yahoogroups.com>
    Sent: Saturday, March 22, 2003 4:37 PM
    Subject: [noparse][[/noparse]basicstamps] Re: ac adapter


    > --- In basicstamps@yahoogroups.com, Newzed@a... wrote:
    > > In a message dated 03/22/2003 19:31:27 Eastern Standard Time,
    > > hard-on@t... writes:
    > >
    > >
    > > > hi, I've been using a 9v battery to power my basic stamp but now
    > I
    > > > found an old ac adapter in my basement which outputs 9v DC at
    > 300mA,
    > > > would that be ok for the basic stamp 2sx?
    > > >
    > > >
    > >
    > > Pretty marginal. You should have at least 500ma.
    > >
    > > Sid
    > >
    > >
    > > [noparse][[/noparse]Non-text portions of this message have been removed]
    >
    > this website mentions only 60mA needed under 'current requirements':
    > http://www.warburtech.com/Basic%20Stamps/BS2SX-IC/BS2SX-IC.htm
    >
    > I was just worried that 300mA would be too much....
    >
    >
    > 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/
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 00:59
    In a message dated 3/22/2003 4:38:20 PM Pacific Standard Time,
    hard-on@t... writes:

    > --- In basicstamps@yahoogroups.com, Newzed@a... wrote:
    > >In a message dated 03/22/2003 19:31:27 Eastern Standard Time,
    > >hard-on@t... writes:
    > >
    > >
    > >>hi, I've been using a 9v battery to power my basic stamp but now
    > I
    > >>found an old ac adapter in my basement which outputs 9v DC at
    > 300mA,
    > >>would that be ok for the basic stamp 2sx?
    > >>
    > >>
    > >
    > >Pretty marginal. You should have at least 500ma.
    > >
    > >Sid
    > >
    > >
    > >[noparse][[/noparse]Non-text portions of this message have been removed]
    >
    > this website mentions only 60mA needed under 'current requirements':
    > http://www.warburtech.com/Basic%20Stamps/BS2SX-IC/BS2SX-IC.htm
    >
    > I was just worried that 300mA would be too much....

    No, 300 ma is not "too much" the stamp will take what it needs. If the stamp
    and periphial equipement will pull more current that your adapter can handle,
    the voltage from the adapter will decrease.

    Plug it in and try it. You will not hurt anything.


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 01:00
    In a message dated 3/22/2003 4:43:35 PM Pacific Standard Time, Newzed@a...
    writes:

    > You could have 3000ma and it would matter. The Stamp only takes what it
    > needs. The 300ma only indicates the capacity of the adapter.
    >
    > Sid

    Sid is CORRECT!


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-03-23 18:15
    the device will only draw what it needs but be careful
    not all adapters are the same the output level seems
    to follow the current rating i have found some rated
    6v 1700 mha with voltage levels unloaded as high as
    21volts in a power surge that could triple over rating
    a 5 volt regulator to destruction so remember the
    rating on the adaptor is for whatever voltage while
    it is under a current load unloaded can be much higher

    --- Newzed@a... wrote:
    > In a message dated 03/22/2003 19:38:26 Eastern
    > Standard Time,
    > hard-on@t... writes:
    >
    >
    > > I was just worried that 300mA would be too
    > much....
    > >
    >
    > You could have 3000ma and it would matter. The
    > Stamp only takes what it
    > needs. The 300ma only indicates the capacity of the
    > adapter.
    >
    > Sid
    >
    >
    > [noparse][[/noparse]Non-text portions of this message have been
    > removed]
    >
    >
    > 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/
    >
    >


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  • ArchiverArchiver Posts: 46,084
    edited 2003-03-24 03:20
    Sam wrote:

    > hi, I've been using a 9v battery to power my basic stamp but now I
    > found an old ac adapter in my basement which outputs 9v DC at 300mA,
    > would that be ok for the basic stamp 2sx?

    Sure, I do this all the time - but some adapters are only
    rectified and don't have any builtin capacitance to smooth out
    the supply voltage. It's best to put the output on a scope
    before commiting to one particular adapter. For those you'll
    have to add your own filter caps as appropriate for your current
    requirements.

    --
    History says King George is gone,
    But I just saw him on the White House lawn!
    He has no bounds, and accepts no borders,
    If Congress won't do it, he "Executive Orders".
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