Are the collector base and emitter on the same output leads? Or is something reversed usually? I'm confused and trying to make a simple rough push pull amplifier doesn't really matter how quality it is if i can just make it i can get going from there..
And is the voltage requirement doubled? I have various power supplys.. a 12 volt. 5 volts and 4.5 volts. all amperage is 1 amps for each DC power supply. is that enough?
And is the voltage requirement doubled? I have various power supplys.. a 12 volt. 5 volts and 4.5 volts. all amperage is 1 amps for each DC power supply. is that enough?
12 volts at 1 amp is plently to make a small amp.
The leads on transistors all vary so you are best looking at the data sheet for each which will show the pinouts.
This is a good reference, just type the device number into the blank box.
Datasheet catalog for integrated circuits, diodes, triacs, and other semiconductors, view
NPN and PNP are different in their polarity. NPN have the emitter arrow pointing out and PNP have it pointing in.
An NPN always has to have the collector more positive then the emitter for it to work. The PNP must have the emitter more positive than the base.
The leads on transistors all vary so you are best looking at the data sheet for each which will show the pinouts.
This is a good reference, just type the device number into the blank box.
Datasheet catalog for integrated circuits, diodes, triacs, and other semiconductors, view
NPN and PNP are different in their polarity. NPN have the emitter arrow pointing out and PNP have it pointing in.
An NPN always has to have the collector more positive then the emitter for it to work. The PNP must have the emitter more positive than the base.
one transistor has these written on it
K D998 212
other one says this on it
K B778 217
they are obviously a pair but i can't find the data sheet for one or the other can't remember which but i found the datasheet for one of them but not the other one. it never comes up with anything accurately describing anything similar to the first one...
K D998 212
other one says this on it
K B778 217
they are obviously a pair but i can't find the data sheet for one or the other can't remember which but i found the datasheet for one of them but not the other one. it never comes up with anything accurately describing anything similar to the first one...
THANK YOU.
So Much! I've been looking everywhere for these silly little datasheets XD
Edit: upon further investigation it appears the first datasheet.... again.. isn't what i have in my hands... it doesn't look anything like whats shown in the datasheet
What I have appears to be a pnp and npn audio amplifier transistor set... but the datasheet says otherwise.
Can someone shed some light on this? I honestly don't know if it's correct that somehow i have a strange transistor that can take the appearance of what's in the datasheet as something else?
So Much! I've been looking everywhere for these silly little datasheets XD
Edit: upon further investigation it appears the first datasheet.... again.. isn't what i have in my hands... it doesn't look anything like whats shown in the datasheet
What I have appears to be a pnp and npn audio amplifier transistor set... but the datasheet says otherwise.
Can someone shed some light on this? I honestly don't know if it's correct that somehow i have a strange transistor that can take the appearance of what's in the datasheet as something else?
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NPN/PNP explains the type of "parts" that the transistor consists of.
NPN: Negative/positive/negative
PNP: the opposite.
From Wikipedia:
NPN: Negative/positive/negative
PNP: the opposite.
From Wikipedia:
NPN
An externally hosted image should be here but it was not working when we last tested it.
The symbol of an NPN BJT. The symbol is "not pointing in."
NPN is one of the two types of bipolar transistors, consisting of a layer of P-doped semiconductor (the "base") between two N-doped layers. A small current entering the base is amplified to produce a large collector and emitter current. That is, when there is a positive potential difference measured from the emitter of an NPN transistor to its base (i.e., when the base is high relative to the emitter) as well as positive potential difference measured from the base to the collector, the transistor becomes active. In this "on" state, current flows between the collector and emitter of the transistor. Most of the current is carried by electrons moving from emitter to collector as minority carriers in the P-type base region. To allow for greater current and faster operation, most bipolar transistors used today are NPN because electron mobility is higher than hole mobility.
A mnemonic device for the NPN transistor symbol is "not pointing in," based on the arrows in the symbol and the letters in the name.[5]
PNP
An externally hosted image should be here but it was not working when we last tested it.
The symbol of a PNP BJT. The symbol "points in proudly."
The other type of BJT is the PNP, consisting of a layer of N-doped semiconductor between two layers of P-doped material. A small current leaving the base is amplified in the collector output. That is, a PNP transistor is "on" when its base is pulled low relative to the emitter.
The arrows in the NPN and PNP transistor symbols are on the emitter legs and point in the direction of the conventional current flow when the device is in forward active mode.
A mnemonic device for the PNP transistor symbol is "pointing in (proudly/permanently)," based on the arrows in the symbol and the letters in the name.
that makes a lot more sense than what was first shown to me.thanks!
And those diagrams show that they Are extremely similar nearly identical! I just need to know which wires go to which lead
if the negative and positive input.. are both base's combined? or is one base hooked to negative input and the other base to positive input? (input signal wires?)
And those diagrams show that they Are extremely similar nearly identical! I just need to know which wires go to which lead
if the negative and positive input.. are both base's combined? or is one base hooked to negative input and the other base to positive input? (input signal wires?)
i dont even know how to hook the speaker up to the transistor leads or which leads the power supply goes to....
is there a way someone could draw a simple diagram showing where each positive and negative lead goes to the transistors? where each individual wire goes? speaker wires to transistor leads input and whatnot? power supply is most important to me and safe the input from DC by using 1uF capacitor? i've searched google for months trying to find something like this but all i find are too simplified push pull amp diagrams that never show which wire even goes where..
is there a way someone could draw a simple diagram showing where each positive and negative lead goes to the transistors? where each individual wire goes? speaker wires to transistor leads input and whatnot? power supply is most important to me and safe the input from DC by using 1uF capacitor? i've searched google for months trying to find something like this but all i find are too simplified push pull amp diagrams that never show which wire even goes where..
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I don't mean this to sound rude, but do you have any idea what an amplifier is ? It's certainly not just a case of connecting a supply to a transistor and then a speaker. If you go to the http://sound.au.com/tcaas/ site and have a look at some of the BASIC class A amplifiers, you will get a better understanding of how an amplifier works.
Or another good read is the Pass website. https://www.passdiy.com/project
Nelson Pass is VERY GOOD at taking amplifiers back to basics and explaining them in simple terms. Take for instance the popular ZEN.. https://www.passdiy.com/project/amplifiers/the-zen-amplifier
Nelson Pass is VERY GOOD at taking amplifiers back to basics and explaining them in simple terms. Take for instance the popular ZEN.. https://www.passdiy.com/project/amplifiers/the-zen-amplifier
All medium power and high power BJTs have the collector as the middle lead. This lead is directly attached to the backplate.
To126 are ecb, To220, To247, To264, To3p are all bce
The only exception to this are the >3legged transistors, eg Onsemi's NJL has the collector as the middle lead of the 5lead package, they are becdd
At low current and low voltage, most BJTs will not be damaged by accidentally swapping PNP & NPN, but when swapped at normal operating voltages they can draw very high current and are usually damaged. A mains bulb tester will often protect against this accidental damage.
To92 and Eline come in a wide variety of lead outs, but as far as I have seen, E is never the middle lead.
To126 are ecb, To220, To247, To264, To3p are all bce
The only exception to this are the >3legged transistors, eg Onsemi's NJL has the collector as the middle lead of the 5lead package, they are becdd
At low current and low voltage, most BJTs will not be damaged by accidentally swapping PNP & NPN, but when swapped at normal operating voltages they can draw very high current and are usually damaged. A mains bulb tester will often protect against this accidental damage.
To92 and Eline come in a wide variety of lead outs, but as far as I have seen, E is never the middle lead.
The flow of heat inside a transistor is always toward the collector or drain.
Thus that terminal usually given the largest of the three available choices.
A big metal tab (and middle leg of same), a metal can with one leg welded.
But the other two terminals might be in any order. Check the spec sheet or
use the diode test on your meter to sort it out...
For an NPN: if you were to connect, use, or measure backward, its still NPN!
But inside, the construction is rarely symmetrical. The collector N is a much
bigger N than the emitter N, and may be doped differently as well. The part
might work if you have the N's connected in wrong order, but not very well.
And you are making he wrong end of the transistor get unusually hot...
For small transistors that aren't expected to run hot anyway, there
may be no externally visible difference in size to tip off which terminal
is which. You are even more reliant upon a valid spec sheet to provide
that information.
If you have a meter with an "HFE" test, you will notice the gain in one
orientation is greater than the other.
Thus that terminal usually given the largest of the three available choices.
A big metal tab (and middle leg of same), a metal can with one leg welded.
But the other two terminals might be in any order. Check the spec sheet or
use the diode test on your meter to sort it out...
For an NPN: if you were to connect, use, or measure backward, its still NPN!
But inside, the construction is rarely symmetrical. The collector N is a much
bigger N than the emitter N, and may be doped differently as well. The part
might work if you have the N's connected in wrong order, but not very well.
And you are making he wrong end of the transistor get unusually hot...
For small transistors that aren't expected to run hot anyway, there
may be no externally visible difference in size to tip off which terminal
is which. You are even more reliant upon a valid spec sheet to provide
that information.
If you have a meter with an "HFE" test, you will notice the gain in one
orientation is greater than the other.
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Iv'e read a lot of your posts. Based on what I have read I believe you have a lot of learning yet to do. Here's a little bit of information on transistor identification:
If what you have is *ANY* variant of the TO220/TO3P/TO247/TO264 case the leads will always be B-C-E for bipolar transistors when viewing the lettering printed on the device. Any exposed metal on the package will be connected to the collector. Devices with an A or a B before the part number will be the PNP device and letters C or D before the part number will be the NPN device for Japanese types of transistors. Generally devices of A and C will be considered higher frequency devices, and devices of B and D will be lower frequency devices, but that is of little consequence for our purposes here.
If you get devices with a J or a K before the part number you will likely have a MOSFET, or possibly some other type of FET. The letter before the part number indicates the polarity, J for the P-channel and K for the N-channel. The pinout can vary, but most devices are of the switching variety and have a pinout of G-D-S, with the metal of the case being the drain. Audio specific devices of the lateral type will have a pinout of G-S-D with the metal of the case being the source.
Read more on the subject of electronics. Lots more. Also, really make some effort to learn how to read a schematic. They show you how to connect everything, just not as a pictorial. It is the language of this hobby and without it you will have great difficulty moving forward. It would be like aspiring to be a rock star on guitar, but not being able to read music. Hope this has helped even just a little.
Thanks JK,
that explanation helps a lot.
Thanks for the patience you are showing in spending time with a beginner, even though he claims otherwise.
I have a saying:
A good Engineer recognises his/her limitations........ and asks for help when they need it.
I have had colleagues who did not think like this, 1 they did not share their knowledge, 2 they never admitted to not knowing. Very dangerous for those who relied on their design integrity.
that explanation helps a lot.
Thanks for the patience you are showing in spending time with a beginner, even though he claims otherwise.
I have a saying:
A good Engineer recognises his/her limitations........ and asks for help when they need it.
I have had colleagues who did not think like this, 1 they did not share their knowledge, 2 they never admitted to not knowing. Very dangerous for those who relied on their design integrity.
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