Finally got around to learning about transistors and this is by far the best transistor site I came around. Feel free to add all you know about how to use different types of transistors around the site

Topic by guyfrom7up 11 years ago

Transistor? Answered

I am constructing the flyback driver found on the power labs website and cant get a 2N3055 transistor quite yet. I do, however, have a bag of transistors i pulled out of CRT monitors. I was wondering if one would be a good substitute for the 2N3055 for driving a new flyback, the number is C4916, the base-collector voltage is 1500 V and the Collector current is 7 Amp

Question by budhaztm 7 years ago  |  last reply 5 years ago


I would like to know if someone could draw up a small circuit using  a TIP3055 as a switch for these led lights,Im running these off a small circuit for a pir sensor, that uses a relay, and i want to use a Transistor or a mosfet  because of size. I just cant do the math for the are the spec. for the led lights."Working input voltage :12vdc working power 36W . working current 5 amp I know that you have to feed the Base with a lower voltage, and the emitter goes to ground, and the collector get the 12vdc. tks for the help. I never was good at algebra in school, don't even remember it,  ha ha ha

Topic by conntaxman 6 years ago  |  last reply 6 years ago

equivalent transistors? Answered

I need equivalent transistors for ac188 and ac187 and is bc548 equivalent to bc148 i couldent find equivalents on google

Question by robot1398 8 years ago  |  last reply 4 years ago

Transistors in series

If I were to put transistors in series (and hook up there bases together through proper biasing resistors) would it increase the voltage capacbility of the circuit? I need a way of switching on and off about 1000 volts really fast. for example, would 2 750 volt transistors in series be able to handle 1500 volts or not? just a HV pic from my old, dead NST

Topic by guyfrom7up 10 years ago  |  last reply 10 years ago

transistor substitute?

Can i use bd 139 instead of bc 547

Question by jumper1111 6 years ago  |  last reply 6 years ago

identifying transistors

Hello all, i have a lot of transistors that are mixed up. how can i ID them? example: on the front markings are .BC 7-25 014. and on the back is the letter Q what transistor is this?

Topic by sasarchiver 7 years ago  |  last reply 7 years ago

DIY Transistor?

Do you think it'd be possible to make a completely homemade transistor? Not a homemade transistor amp or anything, just the transistor. I know, you could just buy one for cents, but you can also just buy a lot of stuff that you can have fun making. What about turning a normal transistor into a phototransistor? Just sand the coating off the silicon?

Question by LeviMan_2001 8 years ago  |  last reply 6 years ago

Complementary transistors

What or which PNP Complementary transistor can I use with a N-Channel  IGBT HGTP10N120BN 35A 1200V NPT   Transistor  ? I really will thank you . I'm building an H- Bridge motor drive. Ed.

Topic by DELETED_applegoose 6 years ago  |  last reply 6 years ago

Choosing a Transistor ? Answered

Hello All.. I wan't to power up a 10A (12v)  loads with a Arduino .. What is best transistor for this job ? Also what is the resistor value to use between Arduino ? Thanks all..

Question by EZELab 7 years ago  |  last reply 7 years ago

Wire Transistor?

How can I make a wire transistor? It needs to work quite well and has to be stable. Please help either with a picture and description or a schematic. Thanks to you guys in advance.

Question by tzq33tdq 6 years ago  |  last reply 6 years ago

What is a transistor ?

What is a transistor (( can it transform voltage for example from 5v to 12v ?? )) Which component can transform low voltage to a little higher voltage ?? Thanks !!

Topic by yousouf 7 years ago  |  last reply 7 years ago

TIP31cg transistor

HI all, im trying to make this project, a led box that flashes to music i purchased a tip31 transistor, but when i got home i discovered it was a top31cg. is this going to be a problem? thanks all!

Topic by i-like-cheese 8 years ago

Transistor question

Hey guys I have a question on transistors. When using for PWM setups, is the difference between each NPN (or PNP) transistor model by its specs? Such as gate voltage, max current, etc. I am making a LED touch setup made by qs, but I want to make it so that the Arduino activates a transistor to turn on a string of lights that the arduino could not power on its own. Here is the setup of the LED string. I want to replace the TIP31 in the wiring diagram with a NPN transistor (like this one). By replacing it, which pins go to which wire and do it have to add anything else to the setup? Will the new setup also work with PWM signals? Thanks! KT Gadget

Topic by KT Gadget 8 years ago  |  last reply 2 years ago

What is a transistor? Answered

Hey guys, I am having problems understanding what is a transistor. When I do a search it shows me that its made of semi-conductor material and stuff, I don't want to know that. I want to know what is does as in a battery supplies power, resistor limits current etc. I would really like it if someone could give me a basic explanation of what is a transistor. Thanks in advance :). -Prickly Potato

Question by The Prickly Potato 4 years ago  |  last reply 4 years ago

help with transistors

Could someone tell me if this will succeed in keeping itself on if the button is hit once?

Topic by James (pseudo-geek) 12 years ago  |  last reply 11 years ago

Transistor Trouble

Hi there, I have been working on controlling a large toy car with a wireless receiver from a smaller toy car, the motors I need to control are rated for 9V but the receiver only outputs 3V, reversing polarity to reverse the motor. I made this schematic using transistors to handle the voltage, but when I built the circuit the transistors began to heat up and there was no output. I am not sure why this is happening, so any help would be greatly appreciated. Thanks, Daniel

Topic by daniel12354 2 years ago  |  last reply 2 years ago

what is this transistor?

I found this transistor in an old genius ps2 mouse (the connection not play station!) it looks like any normal one i've searched google and data sheets searching for it nothing came with any information (one of them said this is a DC motor!) written on it: 536 f   1A exactly. so is it npn or pnp is it power,audio,or general purpose

Question by top.boy 7 years ago  |  last reply 7 years ago

Transistor Substitute

Hey! I'm attempting again to make a wireless FM transmitter. The project plans call for a BC547C transistor, which is pretty common but I don't have any. Can I use a 3904 or a 2N222A instead? Thanks!

Topic by HavocRC 5 years ago  |  last reply 5 years ago

MOSFET Transistor? Answered

Hey Instructables. I am working on a project requiring some MOSFETs but they have to be smaller than the Radioshack IRF510's ( I think I found some ones that are smaller (, but do they have the same functionality? What I mean is, will they work the same way? I believe they will, since they are both labeled as N-Channel MOSFET Transistors, but its always good to check. Thanks in advance!

Question by Adum24 5 years ago  |  last reply 5 years ago

transistors with leds?

New to led lights thought about using on fish tank the one post says to use resistors why is this necessary when using a transformer from alarm clock?

Question by budman95 7 years ago  |  last reply 7 years ago

Transistor help

I got a 5M LED Light Strip. Its controller say it needs 12V 2A but each LED uses 20mA each and there are 300 in this strip which = 6A. I want to cut this strip into 4 segments and power each one using an arduino. 1 strip = 2.1A 2 strip = 1.26A 3 strip = 1.5A 4 strip = 1.14A =6A My question is do I need different transistors for each strip because of the difference in amperage or can I use the same one? If so, which one!? Thanks for your attentions. Bobbay

Topic by Tzla 6 years ago  |  last reply 6 years ago

Transistor vocoder?

Hello, last night i was experimenting with my breadboard, and i came up with an idea, transistors have a supply voltage, which the small voltage controls pitch and volume. but i thought what if i had voice coming in to the supply voltage part(after being super amplified) and the keyboard comes in the control voltage side, would the keyboard not control pitch of voice, while voice modulates? thanks for your help.

Question by ski4jesus 7 years ago  |  last reply 7 years ago

help w/ transistors

Does anyone know a good experiment to teach what transistors do? I have read everything I can find about them and I still don’t understand what they do and how they do it. Can anyone help?

Topic by kendallickes 10 years ago  |  last reply 10 years ago

Transistors are best for melting brains!!

I have been experimenting with transistors for 3 days now, both NPN and PNP. So far I have concluded nothing. I figure the easiest thing to do is to make a transistor work as a switch. With the NPN, the current seems to flow from the base to the emitter automatically. My understanding is that current should flow from the collector + to the emitter- only when I apply voltage +? to the base, is that correct? I don’t even need to connect the collector on the NPN and current flows. I have also read a million things about transistors online. My experiments seem to disprove most(all?) of the findings. This leads me to one conclusion. I’m not doing something right. Maybe I don’t have the right transistors. I have no idea. I have been using radioshack NPN’s (276-2016) and PNP’s (276-1604) When it tried to make a switch with a PNP my voltages was going back through my emitter to ground. If I disconnected it the system(test led) no longer worked. You might need to know that I was using a 5v voltage regulator to supply a 10v 5v and ground leads for my experiments. I was getting odd voltage readings on my circuits so I put diodes on the leads. The diodes stopped my PNP from working(I figured the current was flowing odd ways…back in the 5v+?) and didn’t seem to effect my NPN experiments. So I figure I’m closer on my NPN’s than my PNP’s. I wish I could explain better but my brain is about to melt. My wife is mad at me because I am obsessed with making this work… please help :P

Topic by kendallickes 10 years ago  |  last reply 10 years ago

Where can I buy bc 377 transistors? Answered

I am trying to make a spurt bot, and am having trouble finding the bc 377 transistor which is needed. I need to know where I can buy them, or if there are any other transistors that I can use.

Question by Higgs Boson 7 years ago  |  last reply 7 years ago

What transistors have a very low switching current? Answered

I need a transistor that "switches" when I apply around 0.5 volts/1-10 milliamps to its base? 2N3904 transistors require too high of a switching current(is that what it's called?). Does anyone have suggestions?

Question by seraine 6 years ago  |  last reply 6 years ago


What types of good transistors are there that can take more than 36 volts input for driving FBT? I have a toshiba D2586 its good but dont work well above 20 volts I tried doubling my 18v input to 36v and it lasted only a few miliseconds altough it was big sparks, so is this a feedback or over spike return voltages problem  that it cant handle?can anyone tell me why this happens? and what solution there is? ty very much.

Question by OVERLOADED 7 years ago

any one can tell me that which transistor is similar to tip31?

Question by ddavey1 7 years ago  |  last reply 7 years ago

I need some help identifying transistors?

I have what they all say on them, and I tried googling some of them but cant find data sheets.. I took them off a board from a dvd/vcr  Heres what they say:  c2120    y   og   a1015    gr  og  n1f4m  k306m   a1f4m  k399m a1f4m  k39ym   k2715   h c3195  y  1130 c3195  y 1134   c2785  k06m  h 1815  gh gr c536n  f  od1  c2785  f0bm  How do I figure out what I can use them for? 

Question by 'earl 7 years ago  |  last reply 7 years ago

Electronic knowledge wanted: Transistor/Transistor logic Answered

Hi all. I am embarking on an electronics project and I was hoping to gain some info on using transistors as logic gates in a circuit. I searched both the interwebs and instructables extensively, but all the info I could find was either outdated or was in a level of techno-babble my Noobish hardware skills could not comprehend (been programming for years; Just recently decided to dabble in hardware). To summarize: I want to know how to construct AND, OR, NOT, XOR and the like and integrate it into my circuit using primarily transistors, and maybe some capacitors. Is there something I have gotten mistaken in this premise? Is this really the proper use for a transistor? Should I use something else, is there a better method? Please note that I have little experience in non-software areas (I understand what voltage and amperage is (kinda) and what serial and parallel circuits are, and the proper configurations of positive and negative). I also do not want to use a microcontroller for this; Just me and my wires. I would be immensely thankful for some help. I apologize in advance if I have gotten anything wrong here.

Question by dungeon runner 9 years ago  |  last reply 8 years ago

what is the function of transistor? Answered

Question by Pranjal Joshi 7 years ago  |  last reply 7 years ago

Substitute of Power Transistor

What is the substitute of 2N6292 power transistor? Please suggest a good substitute of 2N6292.It must be an NPN power transistor. Thank you.

Question by SiamB1 2 years ago  |  last reply 2 years ago

AC187 Transistor Alternative???

Hi I was wondering if anyone knew of any Silicon or Germanium alternatives to the AC187 Transistor. Also is the BC548 or BC547 Silicon Transistor an alternative to the AC187 Germanium transistor?  Thanks in advance

Topic by Ikram1ali 4 years ago  |  last reply 3 years ago

Transistor H-bridges

Is it possible to make a transistor H-bridge with PNP transistors or can it only be done with NPN transistors.  As far as my knowledge( or lack thereof) of transistors goes, I think it would be possible, but it would require more than 4 transistors and it would be much more complex, however I could be entirely wrong.  Any input would be helpful, thanks.

Question by jpenn 9 years ago  |  last reply 9 years ago

Transistors in LED matrices?

I'm confused about the purpose served by using transistors in an LED matrix.  Why not simply use current limiting resistors and a shift register?  What purpose do the transistors serve?

Question by KentaGrace 8 years ago  |  last reply 7 years ago

Tube AND transistor amp? Answered

Question by arhodes18 7 years ago  |  last reply 7 years ago

Transistor battery question

Hi, I want to know if I can hook up an 18v 3ah battery to a npn transistor with a max of 1a. Will the transistor only let through 1a or will it get burnt out? Thanks.

Question by RyanF191 1 year ago  |  last reply 1 year ago

SS8550 D331 Transistor

Hi , Guys can you tell me if  2N2222 Transistor is equal ant to SS8550 . It's in an IR circuit . Thanks in advance :D

Topic by UsmanK14 3 years ago  |  last reply 2 years ago

2x bipolar transistor? Answered

If I took 2 similar NPN transistors and connected both the bases together, both the collecters, and both the emitters, then put it into a circuit, what would the 2 transistors do? Would the maximum power dissipation be increased or something? 

Question by .Unknown. 8 years ago  |  last reply 8 years ago

help picking transistor

Me no get no transistors. me need help. me using ltc4060 chip and me need help picking the pnp transistor. heres datasheet,C1,C1003,C1037,C1078,C1088,P7601,D5235it's on page 14 - 15I'm using 3 cells and a charge current of 35 mABTW I'm not stupid, just never really got how to use transistors

Topic by guyfrom7up 11 years ago  |  last reply 11 years ago

Transistor relay with NO and NC?

Does anyone know how to make a solid state relay with a NO contact and a NC?Does anyone have a schematic?Thanks.

Topic by thermoelectric 10 years ago  |  last reply 9 years ago

Passive amplifier with a transistor? Answered

It's possible to build a passive amplifier with a transistor? i have think about something that might work with a capacitor conecting the audio + to the transistor base. not sure if will do, and if it do i don,t know how much resistence is needed on the other end of the circuit. also i'm going to use 2 15 ohm speakers in series.

Question by Misac-kun 7 years ago  |  last reply 7 years ago

Transistor switching problem

I am having trouble using transistors to switch a some LEDs, I have 5 LEDs in parallel being switched by one transistor but each LED is indervidually switched by another transistor. I have given each LED its own resistor and the problem I am having is that when all LEDs are on each LED gets dimmer then if only one was on. I don't really understand why this is happening but I'm not 100% comfortable with transistors and I have probably done something stupid. I have attached a image of how I have wired it up with only two LEDs

Topic by camlv 9 years ago  |  last reply 9 years ago

Choosing a transistor (NPN)? Answered

Hey Guys, Recently I was ordering electrical components online and when I reached transistors I couldn't choose any. I was wondering that can I order any transistor or will it ave to be specific one? I need one for projects like wireless induction, laser tripwires etc. I would really appreciate it if you could help. Thanks in advance -Prickly Potato

Question by The Prickly Potato 4 years ago  |  last reply 6 months ago

Tip31 Transistor alternatives

I teach middle school science, and I'm helping a small group of keen students work on DIY projects.  One of the students wants to try this: It calls for a Tip31 Transistor, which is proving difficult to find, at least in Canada.  The comments section suggests at one point that any NPN transistor will do. Can anyone confirm this?  Or can you suggest more readily available alternatives? Thanks!

Topic by dochockin 3 years ago  |  last reply 3 years ago

Transistor Swithching Voltage? Answered

Looking at this data sheet: How much voltage has to be applied across the base and emitter to switch on a "TIP 3055" transistor? The V-be row is the only thing that looks like it is telling about that, but I don't think that's what I'm looking for (mabey it is?).

Question by Jaycub 7 years ago  |  last reply 7 years ago

Quick Transistor question?

I am using pnp transistors as switches. I finally got a working prototype!!!Anyway my prototype motor runs at .18A and the real motors I want to run are 3.3ACan these PNP's handle that? can you tell me how to figure that out so I'm not always asking simple questions?Thanks!

Topic by kendallickes 10 years ago  |  last reply 10 years ago

Transistor Related Questions?

Hey Guys, I need some help, I need to choose a transistor and get to know how to wire it. I have the following transistors: 6822 ( 2N3904 ( 19001 2N2222A ( TIP42C ( And I need help to choose one that can run an Green LED Strip (16 in.). And also how to wire it. If you can give me the steps to wire it up to the output of a circuit and how to wire it up with the led strip it will be greatly appreciated. Oh and also the voltage at which the transistor turns on should be 2.8-9v ish. Thanks in advance. -Prickly Potato

Question by SA-DIY 3 years ago  |  last reply 3 years ago