Question about transistor breakdown voltage

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage? The same?

Thank you in advance.

Gerb

 

[pimpom]

<Gerbermultit00l@gmail.com> wrote in message
news:ea9b399b-e98c-4a0a-a3f4-d6997c100132@f63g2000hsf.googlegroups.com...

I see in the specification sheet for a darlington transistor
that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage? The same?

It depends on the concept you're trying to understand. If you

simply want to have an idea of the maximum voltage that can be
applied between collector and emitter before breakdown, assuming
that the polarity is in the usual direction, then it could be
said that they are the same.

However, to be technically correct and also specify the polarity
at the same time, they are not the same. For example:

The voltage applied to the collector of an NPN transistor is
normally positive with respect to the emitter. Therefore, the
collector-emitter voltage (whether breakdown or normal operating)
would be given as X volts, whereas for a PNP transistor, it would
be -X volts.

If you give X volts as the emitter-collector voltage, it would
mean that the emitter is positive with respect to the collector.
This is the reverse of the way an NPN transistor is normally
operated. The breakdown voltage would also probably be different
because the base-emitter junction and the base-collector
junctions are made different in practice, although their basic
principles are the same.

 

[pimpom]

<Gerbermultit00l@gmail.com> wrote in message
news:1d0059a7-ecd6-4dea-91a6-6e308e222d25@79g2000hsk.googlegroups.com...
On Oct 23, 2:20 pm, "pimpom" <pim...@invalid.invalid> wrote:

Gerbermultit...@gmail.com> wrote in message

news:ea9b399b-e98c-4a0a-a3f4-d6997c100132@f63g2000hsf.googlegroups.com...>I
see in the specification sheet for a darlington transistor
that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage? The same?

It depends on the concept you're trying to understand. If you
simply want to have an idea of the maximum voltage that can be
applied between collector and emitter before breakdown,
assuming
that the polarity is in the usual direction, then it could be
said that they are the same.

However, to be technically correct and also specify the
polarity
at the same time, they are not the same. For example:

The voltage applied to the collector of an NPN transistor is
normally positive with respect to the emitter. Therefore, the
collector-emitter voltage (whether breakdown or normal
operating)
would be given as X volts, whereas for a PNP transistor, it
would
be -X volts.

If you give X volts as the emitter-collector voltage, it would
mean that the emitter is positive with respect to the
collector.
This is the reverse of the way an NPN transistor is normally
operated. The breakdown voltage would also probably be
different
because the base-emitter junction and the base-collector
junctions are made different in practice, although their basic
principles are the same.

Let me add some clarification to my earlier statement.

The darlington transistor is an NPN device used as a low side
switch.
Emitter is tied to ground. I am interested in understanding what
happens when the collector goes negative with respect to ground.

In this instance, wouldn't the emitter to base junction break
down
first (max rating of 10V)? Current would flow from the emitter,
to
the base, then from the base to collector (one diode drop). So,
total
breakdown voltage in the reverse direction (assuning the
connection
scheme listed above) would be approximately 10.7VDC?

Yes, that's what would happen unless the base is prevented from
being pulled below ground by some other circuitry. This can be
qualitatively demonstrated with a single (non-darlington)
transistor and an analog multimeter set at the high ohmmeter
range. The 9V battery generally used to drive the high resistance
range is higher than the e-b breakdown voltage (usually around
5V). In fact, I often use this to identify the leads of an
unknown transistor. The collector-emitter path is essentially
open in one direction, but conducts in the other direction, but
at a lower level than a single p-n junction.

 

[John Fields]

On Thu, 23 Oct 2008 11:38:34 -0700 (PDT), Gerbermultit00l@gmail.com
wrote:

On Oct 23, 2:20 pm, "pimpom" <pim...@invalid.invalid> wrote:
Gerbermultit...@gmail.com> wrote in message

news:ea9b399b-e98c-4a0a-a3f4-d6997c100132@f63g2000hsf.googlegroups.com...>I see in the specification sheet for a darlington transistor
that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?  The same?

It depends on the concept you're trying to understand. If you
simply want to have an idea of the maximum voltage that can be
applied between collector and emitter before breakdown, assuming
that the polarity is in the usual direction, then it could be
said that they are the same.

However, to be technically correct and also specify the polarity
at the same time, they are not the same. For example:

The voltage applied to the collector of an NPN transistor is
normally positive with respect to the emitter. Therefore, the
collector-emitter voltage (whether breakdown or normal operating)
would be given as X volts, whereas for a PNP transistor, it would
be -X volts.

If you give X volts as the emitter-collector voltage, it would
mean that the emitter is positive with respect to the collector.
This is the reverse of the way an NPN transistor is normally
operated. The breakdown voltage would also probably be different
because the base-emitter junction and the base-collector
junctions are made different in practice, although their basic
principles are the same.

Let me add some clarification to my earlier statement.

The darlington transistor is an NPN device used as a low side switch.
Emitter is tied to ground. I am interested in understanding what
happens when the collector goes negative with respect to ground.

In this instance, wouldn't the emitter to base junction break down
first (max rating of 10V)? Current would flow from the emitter, to
the base, then from the base to collector (one diode drop). So, total
breakdown voltage in the reverse direction (assuning the connection
scheme listed above) would be approximately 10.7VDC?

---
Version 4
SHEET 1 880 680
WIRE 32 32 -208 32
WIRE 224 32 112 32
WIRE 352 32 224 32
WIRE 224 144 224 32
WIRE 32 192 -64 192
WIRE 160 192 112 192
WIRE 352 240 352 32
WIRE -208 256 -208 32
WIRE -64 256 -64 192
WIRE 224 288 224 240
WIRE 288 288 224 288
WIRE -208 384 -208 336
WIRE -64 384 -64 336
WIRE -64 384 -208 384
WIRE 352 384 352 336
WIRE 352 384 -64 384
WIRE -208 432 -208 384
FLAG -208 432 0
SYMBOL npn 160 144 R0
SYMATTR InstName Q1
SYMATTR Value 2N3904
SYMBOL npn 288 240 R0
SYMATTR InstName Q2
SYMATTR Value 2N4401
SYMBOL res 128 176 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R1
SYMATTR Value 3600
SYMBOL voltage -64 240 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value 5
SYMBOL voltage -208 240 R0
WINDOW 3 24 104 Invisible 0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value PULSE(10 -10 0 1 0 1.1)
SYMBOL res 128 16 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R2
SYMATTR Value 100
TEXT -184 416 Left 0 !.tran 1.1 uic


JF

 

On Oct 23, 2:20 pm, "pimpom" <pim...@invalid.invalid> wrote:

Gerbermultit...@gmail.com> wrote in message

news:ea9b399b-e98c-4a0a-a3f4-d6997c100132@f63g2000hsf.googlegroups.com...>I see in the specification sheet for a darlington transistor
that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?  The same?

It depends on the concept you're trying to understand. If you
simply want to have an idea of the maximum voltage that can be
applied between collector and emitter before breakdown, assuming
that the polarity is in the usual direction, then it could be
said that they are the same.

However, to be technically correct and also specify the polarity
at the same time, they are not the same. For example:

The voltage applied to the collector of an NPN transistor is
normally positive with respect to the emitter. Therefore, the
collector-emitter voltage (whether breakdown or normal operating)
would be given as X volts, whereas for a PNP transistor, it would
be -X volts.

If you give X volts as the emitter-collector voltage, it would
mean that the emitter is positive with respect to the collector.
This is the reverse of the way an NPN transistor is normally
operated. The breakdown voltage would also probably be different
because the base-emitter junction and the base-collector
junctions are made different in practice, although their basic
principles are the same.

Let me add some clarification to my earlier statement.

The darlington transistor is an NPN device used as a low side switch.
Emitter is tied to ground. I am interested in understanding what
happens when the collector goes negative with respect to ground.

In this instance, wouldn't the emitter to base junction break down
first (max rating of 10V)? Current would flow from the emitter, to
the base, then from the base to collector (one diode drop). So, total
breakdown voltage in the reverse direction (assuning the connection
scheme listed above) would be approximately 10.7VDC?

Thank you

Gerb

 

[Phil Allison]

<Gerbermultit00l@gmail.com>

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?

** Look at the diagram of the darlington - see a diode drawn from
collector to emitter?

All power darlingtons have them.

Means full conduction from 0.6 volts when subjected to reverse polarity.



....... Phil

 

[Jasen Betts]

On 2008-10-23, Gerbermultit00l@gmail.com <Gerbermultit00l@gmail.com> wrote:

On Oct 23, 2:20 pm, "pimpom" <pim...@invalid.invalid> wrote:

The darlington transistor is an NPN device used as a low side switch.
Emitter is tied to ground. I am interested in understanding what
happens when the collector goes negative with respect to ground.

what's connected to the base?

Bye.
Jasen

 

[John Fields]

On Fri, 24 Oct 2008 11:35:38 +1100, "Phil Allison"
<philallison@tpg.com.au> wrote:

Gerbermultit00l@gmail.com

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?


** Look at the diagram of the darlington - see a diode drawn from
collector to emitter?

All power darlingtons have them.

Means full conduction from 0.6 volts when subjected to reverse polarity.

---
Phil 1, everyone else 0.

JF

 

[Dr. Polemic]

On Fri, 24 Oct 2008 11:35:38 +1100, "Phil Allison" <philallison@tpg.com.au>
wrote:

Gerbermultit00l@gmail.com

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?


** Look at the diagram of the darlington - see a diode drawn from
collector to emitter?

All power darlingtons have them.

Where did you get the idea that the OP was referring to POWER darlingtons?

Besides, it's not true that all power darlingtons have antiparallel diodes.
The General Electric D40K doesn't have one. And, as GE says in one of
their manuals, "The modern monolithic Darlington may contain all or none of
the auxiliary components shown in Figure 7.2 (referring to the antiparallel
diode and built-in base-emitter resistors). It only takes one
counterexample to falsify your assertion.

Means full conduction from 0.6 volts when subjected to reverse polarity.



...... Phil

 

[Dr. Polemic]

On Fri, 24 Oct 2008 09:10:40 -0500, John Fields
<jfields@austininstruments.com> wrote:

On Fri, 24 Oct 2008 11:35:38 +1100, "Phil Allison"
philallison@tpg.com.au> wrote:


Gerbermultit00l@gmail.com

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?


** Look at the diagram of the darlington - see a diode drawn from
collector to emitter?

All power darlingtons have them.

Means full conduction from 0.6 volts when subjected to reverse polarity.

---
Phil 1, everyone else 0.

Apparently not.

JF

 

[John Fields]

On Sat, 25 Oct 2008 09:05:31 -0700, Dr. Polemic <nospam@aol.com> wrote:

On Fri, 24 Oct 2008 09:10:40 -0500, John Fields
jfields@austininstruments.com> wrote:

On Fri, 24 Oct 2008 11:35:38 +1100, "Phil Allison"
philallison@tpg.com.au> wrote:


Gerbermultit00l@gmail.com

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?


** Look at the diagram of the darlington - see a diode drawn from
collector to emitter?

All power darlingtons have them.

Means full conduction from 0.6 volts when subjected to reverse polarity.

---
Phil 1, everyone else 0.

Apparently not.

---
OK.

Phil 1000, you 1

JF

 

[Dr. Polemic]

On Sat, 25 Oct 2008 11:52:20 -0500, John Fields
<jfields@austininstruments.com> wrote:

On Sat, 25 Oct 2008 09:05:31 -0700, Dr. Polemic <nospam@aol.com> wrote:

On Fri, 24 Oct 2008 09:10:40 -0500, John Fields
jfields@austininstruments.com> wrote:

On Fri, 24 Oct 2008 11:35:38 +1100, "Phil Allison"
philallison@tpg.com.au> wrote:


Gerbermultit00l@gmail.com

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?


** Look at the diagram of the darlington - see a diode drawn from
collector to emitter?

All power darlingtons have them.

Means full conduction from 0.6 volts when subjected to reverse polarity.

---
Phil 1, everyone else 0.

Apparently not.

---
OK.

Phil 1000, you 1

Given Phil's normal tendency to mercilessly rag on anyone who makes any
assumption that he considers unwarranted, he must be held to his own high
standard in that respect. Since the OP didn't use the word "power" in any
of his posts, Phil gets 0, not 1000, a forfeit for bad behavior.

If anyone else had said what Phil did, he would probably say something like
this:

CONSIDER THE CONTEXT, IDIOT!!!! THE OP WOULD HAVE SEEN THE DIODE IF IT
WERE IN THE DIAGRAM, AND WOULDN'T BE ASKING THE QUESTION HE DID!!!!!

Only Phil made the assumption that the OP's darlington has a diode;
everybody else assumed that it doesn't. Why do you suppose that is? Which
is the more reasonable assumption?

Just because I only cited one power darlington without a diode doesn't mean
that there aren't more.

But more to the point, it doesn't matter how many power darlingtons have
diodes. If the OP's darlington isn't a power darlington, then it's
irrelevant how many power darlingtons have diodes. You don't get points
for conclusions based on an unwarranted assumption.

Furthermore, if we don't know for sure whether the OP's darlington has a
diode or not, and have no good reason to assume that it does, treating the
case where it doesn't is the useful thing to do.

>JF

 

[Phil Allison]

"Dr. Posturing Pig "

Phil Allison
Gerbermultit00l@gmail.com

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?


** Look at the diagram of the darlington - see a diode drawn from
collector to emitter?

All power darlingtons have them.

Where did you get the idea that the OP was referring to POWER darlingtons?

** 100 volt, NPN low side switch ..... so has all the earmarks.

Plus see the " ? " at the end of the line ????

That means something.

Besides, it's not true that all power darlingtons have antiparallel
diodes.

** All the popular, readily available ones do.

The General Electric D40K doesn't have one.

** Really.

Why don't you go jump in front of an express train - fuckwit.



...... Phil

 

[Dr. Polemic]

On Sun, 26 Oct 2008 11:14:41 +1100, "Phil Allison" <philallison@tpg.com.au>
wrote:

"Dr. Posturing Pig "
Phil Allison
Gerbermultit00l@gmail.com

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

What is its emitter to collector breakdown voltage?


** Look at the diagram of the darlington - see a diode drawn from
collector to emitter?

If there were a diode in the diagram he wouldn't have been asking the
question.

All power darlingtons have them.

Where did you get the idea that the OP was referring to POWER darlingtons?


** 100 volt, NPN low side switch ..... so has all the earmarks.

Small signal darlingtons are very often used as low side switches to turn
on LED's, energize small relays, and they are also often NPN. These things
don't imply power.

Plus see the " ? " at the end of the line ????

That means something.

It means he was asking a question. If a diode were visible in the diagram,
he wouldn't need you to ask him if he could see it.

Besides, it's not true that all power darlingtons have antiparallel
diodes.


** All the popular, readily available ones do.

So that means he couldn't be asking about one of the less popular ones?

The General Electric D40K doesn't have one.


** Really.

Really. And more besides.

Why don't you go jump in front of an express train - fuckwit.

After you.

..... Phil

 

[Phil Allison]

"Dr. Posturing Cunt "

Plus see the " ? " at the end of the line ????

That means something.

It means he was asking a question.

** No - the one I put after the word "emitter".

I was asking the OP a question.

YOU AUTISTIC FUCKING MORON !!!!

Go jump in front of an express train - fuckwit.

 

[Dr. Polemic]

On Sun, 26 Oct 2008 11:14:41 +1100, "Phil Allison" <philallison@tpg.com.au>
wrote:

SNIP

** 100 volt, NPN low side switch ..... so has all the earmarks.

100 volt, NPN low side switch. Those qualities are the exact "earmarks"
of a BC372 small signal darlington for example, and don't imply "power".
The diagram shows there is no diode. If the spec sheet he was looking at
had a diagram with a diode, he would have seen it, and wouldn't have been
asking the question he asked. That's the context you're ignoring, as you
so often accuse others of doing.

Plus see the " ? " at the end of the line ????

That means something.

I notice he hasn't responded to your question. The answer was so obvious
it didn't merit a reply. If there had been a diode in a diagram, he
wouldn't have been asking about reverse breakdown.

Besides, it's not true that all power darlingtons have antiparallel
diodes.


** All the popular, readily available ones do.


The General Electric D40K doesn't have one.


** Really.

Why don't you go jump in front of an express train - fuckwit.



..... Phil

 

[Phil Allison]

"Dr. Posturing Cunthead "


I was asking the OP a question !!!!

YOU AUTISTIC FUCKING MORON !!!!

Go jump in front of an express train - fuckwit.

 

[Eeyore]

Gerbermultit00l@gmail.com wrote:

I see in the specification sheet for a darlington transistor that its
collector to emitter breakdown voltage is 100V.

Vceo, Vceb or Vcev ?

Graham

 

[Eeyore]

Gerbermultit00l@gmail.com wrote:

I am interested in understanding what
happens when the collector goes negative with respect to ground.

And why would that happen ?

Never heard of inverse parallel diodes ?


Graham

 

[Eeyore]

Jasen Betts wrote:

On 2008-10-23, Gerbermultit00l@gmail.com <Gerbermultit00l@gmail.com> wrote:
On Oct 23, 2:20Â pm, "pimpom" <pim...@invalid.invalid> wrote:

The darlington transistor is an NPN device used as a low side switch.
Emitter is tied to ground. I am interested in understanding what
happens when the collector goes negative with respect to ground.

what's connected to the base?

A fairie.