Correct way of using an NPN transistor

Hello,

i am using a transistor for some led but i am not quite sure i am wiring it 100% correctly and i wanna check before i may ruin things.

i am using this transistor: BD136

first page of datasheet:

and this is my circuit based on what i found:

I know the transistor i am using may be a bit overkill but i just had it lying around and dont bother using it.

As led Power source i am using the 3.3V output from one of my ZK-5AD 2-DC motor drivers.
And everything is power from the same 3S li-ion 18650 battery pack.

A BD136 is a PNP transistor

oh, that is strange. Then why does the datasheet say that is it a NPN?

135, 137, 139 != 136
Maybe you mistyped something.
Please clarify.

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wel yes i can see that but what does this sentence mean then?
image

Those are 'companions'.

my first language is not english so i may have understood the meaning of Complement wrong


here is an image of the actual transistor i found

but the arrow points in different directions with both images? what does this mean?

Nice - still, it's not suitable for your circuit.
NPN emitter points out.

How is it not suitable for my circuit? please explain.
is there a way i can modify my ciruit to make it work?

Your schematic does not show a ground connection from the ESP. You really do not know enough to make circuits and should take many lessons before trying to wire anything.

See that arrow on the emitter? It indictes the direction of the conventional current flow. You will see that for a PNP transistor this will be in the opposite direction to an NPN one. You will need to arrange your circuit accordiingly. Also you should note that the voltage at the base needs to be at least 0.7V lower at the emitter, rather then higher, for the transistor to turn on. You may need a pull-up at the base to keep it turned off. You should probably also use a current limiting resistor in series with your LED(s), assuming that is a LED and not an incandescent bulb.

Complement is something that makes complete, or in this case you could say opposite equivalent, so a transistor with the same general characteristics but with the opposite polarity.

Basically your circuit needs to be re-designed (and corrected) to take into account the opposite polarity of the transistor you are trying to use or else find NPN transistor.

here is a full circuit, explaining what is going on:

i dont know exaclty how many Kohm to use but i was thinking of 1Kohm

i dont know how much amp is being drawn by base, then i can calculate my resistor

Post your schematic in the proper orientation so we don't have to lie down to read it. Surely you didn't draw it oriented like you posted it.

sorry my camera flipped it

Thank you.
Does 8X parallel mean that you have 8 LEDs wired in parallel?
You would need to use an NPN transistor to switch the ground side as you have drawn. Also you have switched the labels of the emitter and the collector.
Google transistor switching circuits and redraw your circuit. Also google how to use current limit resistors with LEDs and how to safely use LEDs in parallel.

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how do i do it with a PNP? do i put the leds after the collector? after i switch the collector and emitter?

because a PNP is the only thing i have lying around atm

This might help a little:

Working of Transistor as a Switch - NPN and PNP Transistors

Have a look t the PNP transistor section.

Also; "opposite, opposing"... in geometry, two parts that make a whole right angle