Finding the right IC

Discussion in 'The Projects Forum' started by guardado, Sep 28, 2012.

  1. guardado

    Thread Starter New Member

    Sep 28, 2012
    7
    0
    Hi all,

    So I know a little bit about electronics but not much so I would very much appreciate help. I'm an undergrad at MIT working with a group designing a rocket. I'm a physics major not an electronics major or equivalent but my professor wants me to do this:

    In essence, some male pins plug into a box and some female pins "plug in" on the other side. Within the box there is a transistor. Is there an IC that could wire all of the male pins to the female pins while connecting only one set to the transistor. But that set that goes to the transistor should be user select-able and changeable.

    Any help would be appreciated.

    Thanks.
     
  2. wayneh

    Expert

    Sep 9, 2010
    12,086
    3,024
    And apparently not an English or Logic major. :p

    I mean, I can't understand what you want to accomplish. A transistor is often used as a switch. Do you want it to switch something? Is there a power supply somewhere in this scheme? Maybe you could sketch out a diagram?

    A transistor has 3 pins. Do you want to switch all 3, or just the "control", or base pin? You may just need a manual switch, not an IC.

    And if A is connected to B is connected to C, A is connected to C. You can use diodes to prevent current in the "wrong" direction, though, but they do not leave the signal completely unaltered.
     
    Last edited: Sep 28, 2012
  3. guardado

    Thread Starter New Member

    Sep 28, 2012
    7
    0
    Excuse the crudeness, but maybe this will help get my point across.
     
  4. guardado

    Thread Starter New Member

    Sep 28, 2012
    7
    0
    I appreciate the desire to help, but that's not necessary.

    I have many signals and I want to be able to change which signal goes to the transformer but have the rest of them know not to go there. For example, run1: I have many signals come in 1,2,3,4,5. I had chosen signal 3 to go to the transformer so it does so and the next pass through the circuit and go on to whatever else there is but with which I am not concerned. Run2: I chose 4 to be to go to the transformer and now everything else now "knows" to pass on through.
     
    Last edited: Sep 28, 2012
  5. guardado

    Thread Starter New Member

    Sep 28, 2012
    7
    0
    Ah, I see in my original post I wrote transistor where I should have written transformer. Perhaps that was the cause of some confusion.
     
  6. tracecom

    AAC Fanatic!

    Apr 16, 2010
    3,869
    1,393
    I'm guessing an RS232 pass through with the ability to selectively use some of the connections to be connected to a transformer. Looks like a job for a relay to me.

    How many wires are there? How many may possibily be connected to the transformer? How many are connected to the transformer at a time?

    And of course the most important thing of all: do you have a schematic of what you have so that we can understand what you want?
     
  7. wayneh

    Expert

    Sep 9, 2010
    12,086
    3,024
    Ha, ha, I guess we can rule out art major or technical artist as well. :p (please understand I'm just joking)

    So, most of the conductors appear to pass through, connected all the time. Is that right? We can ignore those.

    It appears that you're concerned with only one of the may conductors, and that the two sides of that one conductor are connected to each other through a transformer winding?

    I can't see what the switch does. Are you trying to select one side or the other of the transformer winding, perhaps to monitor it?
     
  8. wayneh

    Expert

    Sep 9, 2010
    12,086
    3,024
    Oh, my post was late.

    Maybe what you need is called a multiplexer IC. It would be connected to all the lines (or as many as you might need to choose from) and you can program the IC to output the signal from just one of the many input lines.

    The voltage and current involved will likely influence which IC you need.
     
  9. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    I think you could do it with a multi-pole rotary switch.

    You can just turn the switch to select which pair of wires go to the transformer.
     
  10. MrChips

    Moderator

    Oct 2, 2009
    12,414
    3,353
    Maybe besides English, logic, and art, they need to teach communication skills at MIT too.
     
  11. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    I just assumed he was not from an English speaking background? People have been a little unfriendly.

    I aggree that communication could have been better. When asking for help with something unusual it can be good to give all the information in simple "point form", which makes it simple to read when language might be a problem.
     
  12. MrChips

    Moderator

    Oct 2, 2009
    12,414
    3,353
    I have read the op's posts so many times my head is spinning and I still don't get what he is asking.
     
  13. vk6zgo

    Active Member

    Jul 21, 2012
    677
    85
    OK,he wants to be able to switch any line so that that line runs through the transformer winding,& the other lines continue directly.

    To do this,he needs to break the through connection,switch the input & output lines to go through the transformer winding.
    It's giving me a headache,too!:D

    If he doesn't mind having a box with a rotary switch on the front,the easiest way is that which THE_RB suggested.

    If he needs to switch it remotely,or control it from a PC,it becomes a nightmare!
    I guess the question is:-Why does he have to use the transformer?

    If all he needs is to monitor the signal through each selected line,there are other ways of doing it.
     
  14. Duane P Wetick

    Active Member

    Apr 23, 2009
    408
    19
    This kind of looks like a current transformer that can be switched between different circuits. Because its a transformer, it requires AC current, not DC to work. So maybe, the transformer's output lines (secondary connections) can go to an op-amp and signal conditioning IC and then to your computer to read each individual circuit state...

    Cheers...DPW [Everything has limitations...and I hate limitations.]

    I wish I could have gone to MIT...our highschool class salutatorian (2 out of 894) went but dropped out before the his first year was over... Became a lawyer instead.
     
  15. wayneh

    Expert

    Sep 9, 2010
    12,086
    3,024
    It appears to have been taken that way, but it was not intended, and I do apologize to the OP. An attempt at friendly joking ended up being just the opposite.

    The multiplexer idea I suggested may not be any use if the line being tested needs to be opened up so the transformer can be inserted.
     
Loading...