H-bridge to drive a linear actuator

Discussion in 'General Electronics Chat' started by Dritech, Oct 14, 2013.

  1. Dritech

    Thread Starter Well-Known Member

    Sep 21, 2011
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  2. ronv

    AAC Fanatic!

    Nov 12, 2008
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    That is a real nice part. It's probably ok as long as you monitor for over current from a stalled motor.
     
  3. Dritech

    Thread Starter Well-Known Member

    Sep 21, 2011
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    Hi, Thanks for the reply. So is this package more efficient when compared to using 4 mosfets ? How can I calculate the voltage drop please?
     
  4. ronv

    AAC Fanatic!

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    pretty good specs. You might find some a little better, but not much.

    You can do the voltage drop based on the on resistance of the FET. So .009 ohms for 1 and .012 for the other. So at 50 amps you would loose 1.05 volts.
     
  5. Gibson486

    Member

    Jul 20, 2012
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    I use that part. It is my go to part when prototyping. It is really robust. That said, it is not exactly readily available (I think it is obsolete soon) now and I am feeling the pain of finding a replacement because I used this on an actual design. BTW, the updated part is BTN, not BTS (BTS is already done...no more, while BTN is on its way out).
     
  6. SgtWookie

    Expert

    Jul 17, 2007
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    That IS an interesting part.

    Your best bet for that particular line would be to look at Infineon's own page:
    http://www.infineon.com/cms/en/prod...html?channel=db3a304312bae05f0112bdd4f0640048
    If you're in a hurry, consider using the BTN8960TA instead; it's the 4th one from the top of the linked-to page.

    There are very few authorized distributors for these products; and if they DO have stock, it isn't much.
     
  7. Dritech

    Thread Starter Well-Known Member

    Sep 21, 2011
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    Hi, Thanks for the replies.

    @ ronv, do you know the part number of the other bridge please?

    @ Gibson486, unfortunately I did not know that there was an updated version. Yesterday I bought 2pcs BTS from Ebay. What is the main difference please? In the dataheets I cannot notice any differences.

    Thanks in advance.
     
  8. Dritech

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    Sep 21, 2011
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    Thanks for the link.

    True and they are quite expensive.
     
  9. ronv

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    I was thinking discrete parts. I don't know of any other integrated bridges.
     
  10. Dritech

    Thread Starter Well-Known Member

    Sep 21, 2011
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    Besides, how does a surface mount IC such as these can handle up to 33A of current, let alone the PCB tracks ??
     
  11. ronv

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    One of the packages is T0-220 so it can be mounted to a heat sink. The other can be soldered to the board so only about 50C/watt. so that one could probably only do about 14 amps. Here is a trace calculator.

    http://www.4pcb.com/trace-width-calculator.html
     
  12. Gibson486

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    Jul 20, 2012
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    Just from looking at the datasheet for 5 minutes, it looks like it may be the same pin for pin. So, they probably just made some improvements. The first one I see off the bat was that it can handle 40A and some of current instead of 42A on the BTN.
     
  13. Dritech

    Thread Starter Well-Known Member

    Sep 21, 2011
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    Hi again,

    Regarding the BTS7960 H-bridge, in the datasheet application circuit there is no fly-back diodes. Is it necessary to include them when working with high current? Why it is not included in the datasheet schematic?

    Thanks in advance.
     
  14. ronv

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    It uses the ones in the FETs until the FET turns on to bypass the diode.
     
  15. Dritech

    Thread Starter Well-Known Member

    Sep 21, 2011
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    In some H-bridge tutorials they sometimes recommend to use extra external diodes. Is this necessary or are the FET internal diodes safe enough?
     
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