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Is the L6208 a good chip for controlling bipolar stepper motors with the Propel — Parallax Forums

Is the L6208 a good chip for controlling bipolar stepper motors with the Propel

ElectricAyeElectricAye Posts: 4,561
edited 2010-03-15 01:57 in Propeller 1
Hey everyone,

I've been learning how to run stepper motors with the Propeller and so far I've worked through the simple L/R and L/5R controls for a unipolar design but now I thought I might consider a bipolar controller using one of the nifty ready-made chips that seems to "do it all" with the PWM current-limiting concept. Since I'm still insecure about using surface mount stuff, I looked around for a DIP type package and found that the L6208 comes in a PowerDip version (Data sheet attached below.)

I hope to use that chip with a Propeller to operate a Vexta motor, PK266-02a, 2-phase, in bipolar mode:
catalog.orientalmotor.com/item/stepping-motors--1068/pk-series-stepping-motors/pk266-02a?&plpver=1043&seo=110

But because I really never know what I'm doing, I thought I might post this idea to see if there are any egregious errors in my way of thinking. Is there any reason why the L6208 might not work with either the Prop or this kind of motor?

Any comments or other suggestions or other possible chips in a DIP package that a newbie like me might be able to deal with?

many thanks,
Mark
smile.gif

Comments

  • Bill HenningBill Henning Posts: 6,445
    edited 2010-03-13 18:42
    I've used L298's with good success, but it is not a DIP package (still .1" through hole though)

    It does not provide as much current as the L6208, but it worked for my application - and it is much cheaper than the L6208
    ElectricAye said...
    Hey everyone,

    I've been learning how to run stepper motors with the Propeller and so far I've worked through the simple L/R and L/5R controls for a unipolar design but now I thought I might consider a bipolar controller using one of the nifty ready-made chips that seems to "do it all" with the PWM current-limiting concept. Since I'm still insecure about using surface mount stuff, I looked around for a DIP type package and found that the L6208 comes in a PowerDip version (Data sheet attached below.)

    I hope to use that chip with a Propeller to operate a Vexta motor, PK266-02a, 2-phase, in bipolar mode:
    catalog.orientalmotor.com/item/stepping-motors--1068/pk-series-stepping-motors/pk266-02a?&plpver=1043&seo=110

    But because I really never know what I'm doing, I thought I might post this idea to see if there are any egregious errors in my way of thinking. Is there any reason why the L6208 might not work with either the Prop or this kind of motor?

    Any comments or other suggestions or other possible chips in a DIP package that a newbie like me might be able to deal with?

    many thanks,
    Mark
    smile.gif
    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    www.mikronauts.com E-mail: mikronauts _at_ gmail _dot_ com 5.0" VGA LCD in stock!
    Morpheus dual Prop SBC w/ 512KB kit $119.95, Mem+2MB memory/IO kit $89.95, both kits $189.95 SerPlug $9.95
    Propteus and Proteus for Propeller prototyping 6.250MHz custom Crystals run Propellers at 100MHz
    Las - Large model assembler Largos - upcoming nano operating system
  • ElectricAyeElectricAye Posts: 4,561
    edited 2010-03-14 19:40
    Bill Henning said...
    I've used L298's with good success, but it is not a DIP package (still .1" through hole though)....

    Hi Bill,

    yes, somebody else suggested that to me, too. It looks like a good chip but can you drive that directly using the Propeller or do you need to interface it with something like the L297? If you need an L297, then it seems to me the cost works out about the same, true??? My intent was to use one Propeller to control perhaps 5 stepper motors, so I didn't want to use up too many Propeller pins with too many "mindless" tasks.


    thanks,
    Mark


    smile.gif
  • SapiehaSapieha Posts: 2,964
    edited 2010-03-14 20:00
    Hi ElectricAye


    You can drive both IC's with Propeller but.
    1. L6208 need use 3 (+ 1 Speed clocking) pins of Propeller and have already direction and half/full step inbuild already.
    2. L298 need use 4 pins of Propeller and You need driver that have inbuild driving of direction of steping, half/full steps in it. As all 4 pins drive directly coils in steper.

    Regards

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Nothing is impossible, there are only different degrees of difficulty.
    For every stupid question there is at least one intelligent answer.
    Don't guess - ask instead.
    If you don't ask you won't know.
    If your gonna construct something, make it·as simple as·possible yet as versatile as posible.


    Sapieha
  • Bill HenningBill Henning Posts: 6,445
    edited 2010-03-14 23:11
    Sapieha is right, you have lower level of control with an L298... but it is much cheaper.

    I've used an L298 to control standard DC motors, DC motors geared waaaay down (224:1), and stepper motors.
    ElectricAye said...
    Bill Henning said...
    I've used L298's with good success, but it is not a DIP package (still .1" through hole though)....

    Hi Bill,

    yes, somebody else suggested that to me, too. It looks like a good chip but can you drive that directly using the Propeller or do you need to interface it with something like the L297? If you need an L297, then it seems to me the cost works out about the same, true??? My intent was to use one Propeller to control perhaps 5 stepper motors, so I didn't want to use up too many Propeller pins with too many "mindless" tasks.


    thanks,
    Mark


    smile.gif
    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    www.mikronauts.com E-mail: mikronauts _at_ gmail _dot_ com 5.0" VGA LCD in stock!
    Morpheus dual Prop SBC w/ 512KB kit $119.95, Mem+2MB memory/IO kit $89.95, both kits $189.95 SerPlug $9.95
    Propteus and Proteus for Propeller prototyping 6.250MHz custom Crystals run Propellers at 100MHz
    Las - Large model assembler Largos - upcoming nano operating system
  • Peter JakackiPeter Jakacki Posts: 10,193
    edited 2010-03-14 23:29
    Remember to compare apples with apples. The 298 needs eight 2A fast diodes + big heatsink + L297 chip. Seriously, is the bulkier L298 a better option than the L6208? Newark have the L6208 in DIP for around $11.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    *Peter*
  • SapiehaSapieha Posts: 2,964
    edited 2010-03-14 23:42
    Hi Peter Jakacki

    I never compare in that maner - Always use what is needed for Design that I work on and how much I can need to correct function.

    You are not correctly right. To drive Stepers and DC motors Yuo ned only diodes. L297 is optional and if You will drive DC motors not needed at all.

    Regards
    Christoffer J

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Nothing is impossible, there are only different degrees of difficulty.
    For every stupid question there is at least one intelligent answer.
    Don't guess - ask instead.
    If you don't ask you won't know.
    If your gonna construct something, make it·as simple as·possible yet as versatile as posible.


    Sapieha
  • Peter JakackiPeter Jakacki Posts: 10,193
    edited 2010-03-14 23:52
    Compare apples with apples I say. If you drive the L298 without the L297 then you do not have current control or chopping and we are not trying to drive a toy unipolar at this stage, so current control is necessary. Wouldn't you agree?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    *Peter*
  • ElectricAyeElectricAye Posts: 4,561
    edited 2010-03-15 01:57
    Sapieha said...
    .... To drive Stepers and DC motors Yuo ned only diodes. L297 is optional and if You will drive DC motors not needed at all...

    That is somewhat how I did it with the so-called L/5R version of control. I used IRF3708 mosfets and placed some Schottky diodes across the motor windings to deal with the flyback currents, but I'm trying to advance beyond that basic technique so I can perhaps get better efficiency. So it seems to me that using an L297 + L298... or to use something like the L6208 is necessary to get better performance. The L6208 seems a bit pricey but it appears to me that this one chip "does it all" with just a handful of external components that are not too bulky. In fact, it almost sounds too good to be true to me, which is why I posted my question on the forum: I wanted to double check with all you forum gurus before I got too excited about it.

    Simply put, I'm just trying to get a warm fuzzy here.

    thanks guys,
    Mark
    smile.gif
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