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Quick Question About a Transistor

Supercap2F

Mar 22, 2014
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Hey Everyone!

It would be really hard to explain why I'm asking this question, so just go with it.:D Would it be bad to do this: (leave the collector attached to nothing while the transistor is power up)38KHZTR.JPG
Regards

Dan
 

BobK

Jan 5, 2010
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Well, you have just invented the diode! Actually the Zener diode with about a 6V reverse breakdown.

Bob
 

Supercap2F

Mar 22, 2014
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It is not going to have nothing hooked up to the collector all the time. This is just kind of a stand by wiring. So would it be bad to leave it like that for a while?

Thanks :D

Dan
 

davenn

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Sep 5, 2009
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no its not going to harm the transistor

Technically this transistor isn't really "powered up" unless you have supply voltage on the collector

BUT why on earth would you want to do that ?
what is your mission?


Dave
 

Supercap2F

Mar 22, 2014
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OK, Thanks Dave!

davenn said:
BUT why on earth would you want to do that ? what is your mission?

I'm driving 6 IR LEDs at 38kHz for 6 TSOP4038s sensors on a robot. The robot has edge sensors too, which have to be calibrated. I can't calibrate them when the TSOP4038s are sending signals to the microcontroler. So I have two options, I can unplug the IR LEDs from the main board and leave the transistor with nothing on the collector, or I can put tape over the IR LEDs, which would be harder. o_O

Regards

Dan
 
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(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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If that circuit works with the LEDs in place, it will do absolutely no harm to remove the LEDs

What you have created is an unused open-collector output. Nothing to be afraid of.
 
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