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SV: [basicstamps] Driver chip... — Parallax Forums

SV: [basicstamps] Driver chip...

ArchiverArchiver Posts: 46,084
edited 2003-03-09 04:44 in General Discussion
Greetings!

So, there's no CMOS buffer/line driver chip that can deliver the power
needed, then?

*Sigh*

Seems like I have to double the size of the battery pack...

A pity for the BS1 runs very nicely at 3V.

:-)
Trygve


Opprinnelig melding
Fra: Mark Hillier [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=zGftN4DD6QpcRu94x6RXzssam0CQ5l4WNYUJOYjhO-FX8ru4o8rcPci_5htZ6kVg_11k6GtWUJA]Mark@H...[/url
Sendt: 6. mars 2003 18:01
Til: basicstamps@yahoogroups.com
Emne: Re: [noparse][[/noparse]basicstamps] Driver chip...




> Greetings!
>
> I'm working on a low-power/low-voltage project using a BS1, and need a
> H-bridge or just a driver with totempole output stage that can sink/source
> 50 - 100mA and operate at 3V...
>
> Anyone know of such a chip?

I was going to say the L293D would be perfect -until I saw the 3 volt
part.

Most semiconductors designed for 3 volt systems are going to be
difficult to get in small quantities and will almost certainly be
surface mount parts.

You may find making your own from discrete components a
practical alternative in this case.

Mark Hillier, VE6HVW
President, HVW Technologies Inc.
Canadian Distributors of Parallax Products and other Neat Stuff
Tel: (403)-730-8603 Fax: (403)-730-8903
http://www.HVWTech.com
** New Breadboard Voltage Regulator (BVR) -A plugable +5 Volt
power supply !


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Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-03-07 20:04
    At 08:26 AM 3/7/03 +0100, Trygve Henriksen wrote:

    >So, there's no CMOS buffer/line driver chip that can deliver the power
    >needed, then?
    >A pity for the BS1 runs very nicely at 3V.

    There are a number of discrete designs. One of the nicest I've seen is
    used by the BEAM robotics people. Check out <www.solarbotics.com> and the
    BEAM group on Yahoogroups.

    Holler if you can't find the schematic - I saw it again recently.

    dwayne

    --
    Dwayne Reid <dwayner@p...>
    Trinity Electronics Systems Ltd Edmonton, AB, CANADA
    (780) 489-3199 voice (780) 487-6397 fax

    Celebrating 19 years of Engineering Innovation (1984 - 2003)
    .-. .-. .-. .-. .-. .-. .-. .-. .-. .-
    `-' `-' `-' `-' `-' `-' `-' `-' `-'
    Do NOT send unsolicited commercial email to this email address.
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  • ArchiverArchiver Posts: 46,084
    edited 2003-03-08 13:06
    greetings!

    Yes, that chip would be overkill...

    I need to control two small DC motors; they're those vibrator types used in
    pagers and cell-phones...

    first I tried to connect one directly to two of the IO pins of the BS1 and
    use that as a H-bridge...
    By pulling one pin low and the other high, the motor ran in one direction,
    and inverting the levels made it run the other way...

    But...
    That was when the motor was entirely without load.
    As soon as I mounted anything on the driveshaft it drew too much power for
    the BS1.

    I really don't want to go to 5V because I'm trying to make the design as
    small as possible, and intend to use a 3V 'button' type cell. (Won't give me
    more than 15 - 30 minutes running time, but that's all that's needed :-)

    What I'm making?
    A 'MilliBot'...
    Microbots are associated with those Transformers things and probably
    trademarked)
    Nanobots are sooooo overhyped...
    (I'll put up a section on my website as soon as I get something to work)

    Oh well, I'll check the Solarbotics site and see what they have of designs
    and drivers.

    :-)
    Trygve


    Opprinnelig melding
    Fra: Dennis P. O'Leary [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=qYN0iwr6pqfarZ9bdqf2OFufO442esQaflqMy3FrLQ6IKCDiNODouSIPkCUCcXrQuyrJEh_RCyymNgVw7_yY]doleary@e...[/url
    Sendt: 7. mars 2003 19:58
    Til: basicstamps@yahoogroups.com
    Emne: RE: [noparse][[/noparse]basicstamps] Driver chip...


    It may be overkill for your application, but the Allegro 3967 is a
    microstepping bipolar driver that runs at 3.0v to 5.5v logic supply
    voltage. It's supplied in a 24-pin surface mount package.

    Dennis

    Original Message
    From: Trygve Henriksen [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=A-kPPVwN_ChVVU4dT6oJaWV2gqMZWzRoOvI-DQb6jnHmOv_97qbWW_CIxl34ULeW1kv1jcU-9M2jVIu876ovg3j5]trygve.henriksen@v...[/url
    Sent: Thursday, March 06, 2003 11:26 PM
    To: 'basicstamps@yahoogroups.com'
    Subject: SV: [noparse][[/noparse]basicstamps] Driver chip...


    Greetings!

    So, there's no CMOS buffer/line driver chip that can deliver the power
    needed, then?

    *Sigh*

    Seems like I have to double the size of the battery pack...

    A pity for the BS1 runs very nicely at 3V.

    :-)
    Trygve


    Opprinnelig melding
    Fra: Mark Hillier [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=GYatdaPFVFVxOZYiTgqISsV0Fzm4dYGmSnPgsmzi9ErOgZr179C33Vxpn9WfVgFRvopYDRLbGL-FaVg]Mark@H...[/url
    Sendt: 6. mars 2003 18:01
    Til: basicstamps@yahoogroups.com
    Emne: Re: [noparse][[/noparse]basicstamps] Driver chip...




    > Greetings!
    >
    > I'm working on a low-power/low-voltage project using a BS1, and need a

    > H-bridge or just a driver with totempole output stage that can
    > sink/source 50 - 100mA and operate at 3V...
    >
    > Anyone know of such a chip?

    I was going to say the L293D would be perfect -until I saw the 3 volt
    part.

    Most semiconductors designed for 3 volt systems are going to be
    difficult to get in small quantities and will almost certainly be
    surface mount parts.

    You may find making your own from discrete components a
    practical alternative in this case.

    Mark Hillier, VE6HVW
    President, HVW Technologies Inc.
    Canadian Distributors of Parallax Products and other Neat Stuff
    Tel: (403)-730-8603 Fax: (403)-730-8903
    http://www.HVWTech.com
    ** New Breadboard Voltage Regulator (BVR) -A plugable +5 Volt
    power supply !


    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.


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    http://docs.yahoo.com/info/terms/


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    from the same email address that you subscribed. Text in the Subject
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    To UNSUBSCRIBE, just send mail to:
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  • ArchiverArchiver Posts: 46,084
    edited 2003-03-09 04:44
    At 08:26 AM 3/7/03 +0100, Trygve Henriksen wrote:

    >So, there's no CMOS buffer/line driver chip that can deliver the power
    >needed, then?
    >
    >A pity for the BS1 runs very nicely at 3V.

    Couple of suggestions: discrete H-bridge (part of a BEAM walker)
    <http://groups.yahoo.com/group/beam/files/Phototropic_2motor_walker_with_sensors\
    .gif
    >

    Ignore parts of the circuit you don't need but the H-bridge should work for
    you.

    Also - consider using 74AC240 type inverters. You get 8 inverters per
    package, each good for about 24 mA. Parallel as many as you need (2 groups
    of 4 gives you 1- H-bridge good for about 100 mA in 1 package).

    Note that 74AC chips are good for about 24 mA per output as opposed to 74HC
    parts at about 6 mA per output. This is one situation where it does pay to
    use the AC family.

    Hope this helps!

    dwayne

    --
    Dwayne Reid <dwayner@p...>
    Trinity Electronics Systems Ltd Edmonton, AB, CANADA
    (780) 489-3199 voice (780) 487-6397 fax

    Celebrating 19 years of Engineering Innovation (1984 - 2003)
    .-. .-. .-. .-. .-. .-. .-. .-. .-. .-
    `-' `-' `-' `-' `-' `-' `-' `-' `-'
    Do NOT send unsolicited commercial email to this email address.
    This message neither grants consent to receive unsolicited
    commercial email nor is intended to solicit commercial email.
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