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Basic Stamp 2 power supply — Parallax Forums

Basic Stamp 2 power supply

blacksheep45blacksheep45 Posts: 41
edited 2009-02-04 14:50 in BASIC Stamp
Hello,

I am trying to connect up·a basic stamp 2·on a breadboard and i was wondering about the connections from the supply?

Do i connect the·V- (from the supply)·to the·Vss (pin 23·on the Stamp)·and the V+ (from the supply)·to the·Vin (pin 24·on the Stamp)·or does V+ connect to the·Vdd (pin 21·on the Stamp)?

The Supply is a Regulated Power supply set to 4.5V

I have already blown 1 stamp by connecting V+ to pin 24 and V- to pin 23. Does anyone know the correct way of connecting a bs2 to a power supply.

Kind Regards

Shaun

Comments

  • dandreaedandreae Posts: 1,375
    edited 2009-02-03 15:22
    The 4.5v supply will not work with the BS2.· You'll need to use a 5v supply if you are connecting to Vdd.· If you have a 6 to 12 volt supply you will need to connect to Vin.· Vss is equal to ground.· Vin is equal to voltage in.· Vdd is equal to regulated 5v.· Make sure the positive lead is connected to Vin or Vdd·depending on the supply being used and the negative lead is connected to Vss.·

    Dave

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    Dave Andreae

    Parallax Tech Support·
  • blacksheep45blacksheep45 Posts: 41
    edited 2009-02-03 16:09
    Dave,

    If i had the 4.5V input connected to the Vin pin would that be able to blow the stamp, as that is what happened when i first tried this.

    Regards

    Shaun
  • Beau SchwabeBeau Schwabe Posts: 6,559
    edited 2009-02-03 16:12
    blacksheep45,

    It shouldn't unless the polarity was backwards.

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    Beau Schwabe

    IC Layout Engineer
    Parallax, Inc.
  • UghaUgha Posts: 543
    edited 2009-02-03 16:16
    The stamp has an internal regulator that takes VIN and regulates it to +5 volts for VDD.

    If you have a 100% clean supply that is EXACTLY 5 volts, you can put it directly to VDD (I often run from one BOE to another using this).

    However, unless your sure about the power, you should connect it to VIN so the stamp's internal regulator can clean it up.

    Unfortunately, all regulators "use up" some power on their own. This means that in order to get +5 volts, you need a supply higher than +5.
    It doesn't have to be clean, however, because the regulator will do that for you.

    Also remember that anything over the absolute min required for the regulator to function, is transformed into heat. So assuming the regulator
    has a 1 volt internal drop (the power it uses up to run), a 6 volt supply would be ideal.

    Anything higher has to be burned off as heat. This isn't always a bad thing, just keep it in mind... I personally wouldn't put anything higher than
    9 volts on the stamp's internal regulator but Dave Andreae knows more than me so I guess 12volts is fine [noparse]:)[/noparse]

    The best bet for what to do is the same thing the BOE does, it uses an external regulator to clean up the power before sending it to VDD. This
    ensures that the power is absolutely clean and it keeps the Stamp from having to deal with any excess heat.

    Can you define "blown"? Perhaps the damaged stamp is repairable.
  • blacksheep45blacksheep45 Posts: 41
    edited 2009-02-03 17:49
    I have checked the connections using a multimeter and the polarity was the correct way around and the input voltage was 4.5V and the stamp blew, i know this from checking it on a PDB and getting the message "no stamp found". Does anyone know any other possible reason for this?

    Regards

    Shaun
  • dandreaedandreae Posts: 1,375
    edited 2009-02-03 18:16
    Please contact me at dandreae@parallax.com regarding your damaged BS2.

    Dave

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    Dave Andreae

    Parallax Tech Support·
  • AmaralAmaral Posts: 176
    edited 2009-02-03 18:20
    Sorry , but .. the polarity was correct .. or was it the way around ?? (by my undertanding thouse are oposites cocepts )

    have you ever porgramed a BS on this PDB with your connections ?? or this is something to be checked ?

    Can you apply something like 6V to the vin .. and check the voltage on the Vdd ( it should be 5V , this way you will know that the stamp regulator is ok )

    Hope to help

    Amaral
  • BarbzBarbz Posts: 8
    edited 2009-02-03 23:11
    Hello everyone.... I seem to be having similar problems in terms of
    No Basic Stamps Found. Am I supposed to use the jumper wires
    to complete the assembly of my sumo bot? I do have fresh batteries
    that are attached to the robot. What am I doing wrong? Haaalllppp!

    Barbz
  • dandreaedandreae Posts: 1,375
    edited 2009-02-03 23:20
    Barbz said...
    Hello everyone.... I seem to be having similar problems in terms of
    No Basic Stamps Found. Am I supposed to use the jumper wires
    to complete the assembly of my sumo bot? I do have fresh batteries
    that are attached to the robot. What am I doing wrong? Haaalllppp!

    Barbz
    Let's have you start a new thread and we can answer it under your subject regarding the Sumo-Bot.· Your case seems to be a little bit different.

    Thanks,

    Dave

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    Dave Andreae

    Parallax Tech Support

    Post Edited (Dave Andreae (Parallax)) : 2/3/2009 11:39:52 PM GMT
  • blacksheep45blacksheep45 Posts: 41
    edited 2009-02-04 13:24
    Hello,

    Attached below is the circuit diagram for how i connected this circuit, the motor wires are connected to the ULN2003A correctly as i have had this circuit working using my professional development board.

    I don't know why the stamp has blown but i hope someone can help me.

    Regards

    Shaun
    bmp
    bmp
    BS2_Motor.bmp
    196K
  • dandreaedandreae Posts: 1,375
    edited 2009-02-04 14:50
    I suggest using a separate power supply for the motor and BS2.··Make sure·you have a common ground on your board.

    Dave

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    Dave Andreae

    Parallax Tech Support·
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