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Quick BS2-IC spec question — Parallax Forums

Quick BS2-IC spec question

UghaUgha Posts: 543
edited 2009-01-31 20:09 in BASIC Stamp
I'm explaining stamps to a friend and I want to make sure I got the specs correct...

Each pin can handle 25ma max and each group of 8 pins can handle a total of 50ma max.

Does that mean pins 0-7 can handle 50ma and pins 8-15 can handle another 50ma for a
total of 100ma used at any one time?

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2009-01-31 15:40
    Yes
  • Craig EidCraig Eid Posts: 106
    edited 2009-01-31 16:57
    Ugha,

    You can increase the drive current current to 60mA for each group of 8 pins and a total of 120mA by using the BS2se/sx or any of the BS2p family of modules. If you are looking at driving a high current load, consider the L293D quad driver from TI··http://focus.ti.com/lit/ds/symlink/l293.pdf·that will handle 600mA/driver. You will need to factor in heat-sinking at higher loads and add transient protection if you are driving an inductive
    load (relay,solenoid or motor).

    Craig
  • UghaUgha Posts: 543
    edited 2009-01-31 17:57
    Thanks for the info guys...
    It's good to have my facts straight [noparse]:)[/noparse]

    Craig Eid: Have you tried a SN754410 H-bridge chip? They can handle 1amp instead of the 600ma limitation of the L293D. It also has the same pinout so its easy to drop it in.
    The best of all, it has flyback diodes already in place so you can connect almost any small load with no external components.
  • Craig EidCraig Eid Posts: 106
    edited 2009-01-31 20:04
    Ugha,

    Thanks for catching my error earlier this morning - the L293D, rated at 600mA, includes the clamping diodes while the·L293, rated at 1000ma, does not·include the clamping diodes. I will take a look at the SN754410 due to the lower price.



    Craig
  • UghaUgha Posts: 543
    edited 2009-01-31 20:09
    Great... I've used a couple SN754410s in my various experiments and I've been quite happy with the results.

    However, these are the ONLY h-bridges I've tried, so please let me know if you find out that a flavor of the L293 is, indeed, a better chip as I intend to order
    more H-bridges in the next couple months.
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