What characterizes a powerFET for audio use?

[N_Cook]

Other than p channel in this case , same for BUZ901P nch
eg BUZ906P 200V, 8A ,datasheet says
"POWER MOSFETS FOR
AUDIO APPLICATIONS"
but also
"FEATURES ... (for use in)
HIGH SPEED SWITCHING ... "

Would a powerFET designed solely for high speed switching use and 125W
rating be derated in power handling terms to only 50W say for linear 10
Hz use. Or secondary oscillation liability if paralleled up devices? or
some other operational failing in audio use not found with smps say ?

 

[Phil Allison]

"Nutcase Kook" is a pig ignorant pommy cunt

Other than p channel in this case, same for BUZ901P nch
eg BUZ906P 200V, 8A ,datasheet says
"POWER MOSFETS FOR
AUDIO APPLICATIONS"
but also
"FEATURES ... (for use in)
HIGH SPEED SWITCHING ... "

** The Semelab app note makes it pretty clear there is a HUGE difference
between "switching" and audio ( ie lateral) power mosfets.

http://products.semelab-tt.com/pdf/ApplicationNoteAlfet.pdf

Would a powerFET designed solely for high speed switching use and 125W
rating be derated in power handling terms to only 50W say for linear 10 Hz
use. Or secondary oscillation liability if paralleled up devices? or some
other operational failing in audio use not found with smps say ?

** Yawnnnnnnnnnnnnnnn....

More brainless, fucking TROLLING !!!!!!!

FOAD you vile pommy cunthead.



..... Phil

 

[dave]

On 01/01/2014 02:09 AM, Phil Allison wrote:

"Nutcase Kook" is a pig ignorant pommy cunt


Other than p channel in this case, same for BUZ901P nch
eg BUZ906P 200V, 8A ,datasheet says
"POWER MOSFETS FOR
AUDIO APPLICATIONS"
but also
"FEATURES ... (for use in)
HIGH SPEED SWITCHING ... "


** The Semelab app note makes it pretty clear there is a HUGE difference
between "switching" and audio ( ie lateral) power mosfets.

http://products.semelab-tt.com/pdf/ApplicationNoteAlfet.pdf


Would a powerFET designed solely for high speed switching use and 125W
rating be derated in power handling terms to only 50W say for linear 10 Hz
use. Or secondary oscillation liability if paralleled up devices? or some
other operational failing in audio use not found with smps say ?

** Yawnnnnnnnnnnnnnnn....

More brainless, fucking TROLLING !!!!!!!

FOAD you vile pommy cunthead.



.... Phil

"Figure of Merit" in pulsed applications vs "efficiency" in linear
applications. RMS Power is measured in heating ability v DC.

 

[William Sommerwerck]

"dave" wrote in message
news:Mpmdnce3Qvd7g1nPnZ2dnUVZ_rWdnZ2d@earthlink.com...

"Figure of Merit" in pulsed applications vs "efficiency"
in linear applications.

Any (???) device can produce more peak power in pulsed mode than continuous,
because it spends less time in the region where it dissipates the most power.


> RMS power is measured in heating ability versus DC.

There is no such thing (other than in a mathematical sense) as RMS power.
Voltage and current can have RMS (root-mean-square) values. Squaring voltage
and dividing by resistance, or squaring current and multiplying by resistance
produces the //average// power.

 

[dave]

On 01/01/2014 06:28 AM, William Sommerwerck wrote:

"dave" wrote in message
news:Mpmdnce3Qvd7g1nPnZ2dnUVZ_rWdnZ2d@earthlink.com...

"Figure of Merit" in pulsed applications vs "efficiency"
in linear applications.

Any (???) device can produce more peak power in pulsed mode than
continuous, because it spends less time in the region where it
dissipates the most power.


RMS power is measured in heating ability versus DC.

There is no such thing (other than in a mathematical sense) as RMS
power. Voltage and current can have RMS (root-mean-square) values.
Squaring voltage and dividing by resistance, or squaring current and
multiplying by resistance produces the //average// power.

http://www.learningaboutelectronics.com/Articles/RMS-voltage-and-current-explained.php

The audio duty cycle makes the device heat up more than pulsating full
on/full off does. That's the spec and the spec is based on a temperature
that will destroy the gate, source, drain, diode, etc. In audio service
an FET is always drawing some current, due to the high turn-on
threshold. The bias is just slightly above cutoff. Many amps use this
quiescent current to set the bias, either measured directly or by
measuring current draw at the mains.

 

[dave]

On 01/01/2014 06:28 AM, William Sommerwerck wrote:

"dave" wrote in message
news:Mpmdnce3Qvd7g1nPnZ2dnUVZ_rWdnZ2d@earthlink.com...

"Figure of Merit" in pulsed applications vs "efficiency"
in linear applications.

Any (???) device can produce more peak power in pulsed mode than
continuous, because it spends less time in the region where it
dissipates the most power.


RMS power is measured in heating ability versus DC.

There is no such thing (other than in a mathematical sense) as RMS
power. Voltage and current can have RMS (root-mean-square) values.
Squaring voltage and dividing by resistance, or squaring current and
multiplying by resistance produces the //average// power.


And FOM is used (by me) because the efficiency is above 100%.

 

[Maynard A. Philbrook Jr.]

In article <yoGdnWbbYokO7lnPnZ2dnUVZ_qidnZ2d@earthlink.com>,
ricketzz@earthlink.net says...

On 01/01/2014 06:28 AM, William Sommerwerck wrote:
"dave" wrote in message
news:Mpmdnce3Qvd7g1nPnZ2dnUVZ_rWdnZ2d@earthlink.com...

"Figure of Merit" in pulsed applications vs "efficiency"
in linear applications.

Any (???) device can produce more peak power in pulsed mode than
continuous, because it spends less time in the region where it
dissipates the most power.


RMS power is measured in heating ability versus DC.

There is no such thing (other than in a mathematical sense) as RMS
power. Voltage and current can have RMS (root-mean-square) values.
Squaring voltage and dividing by resistance, or squaring current and
multiplying by resistance produces the //average// power.


And FOM is used (by me) because the efficiency is above 100%.

Oh really? have you found some over unity energy somewhere?

Jamie

 

[Jeff Liebermann]

On Wed, 1 Jan 2014 06:28:29 -0800, "William Sommerwerck"
<grizzledgeezer@comcast.net> wrote:

"dave" wrote in message
news:Mpmdnce3Qvd7g1nPnZ2dnUVZ_rWdnZ2d@earthlink.com...

"Figure of Merit" in pulsed applications vs "efficiency"
in linear applications.

Any (???) device can produce more peak power in pulsed mode than continuous,
because it spends less time in the region where it dissipates the most power.


RMS power is measured in heating ability versus DC.

There is no such thing (other than in a mathematical sense) as RMS power.
Voltage and current can have RMS (root-mean-square) values. Squaring voltage
and dividing by resistance, or squaring current and multiplying by resistance
produces the //average// power.

RMS power is quite real. A true-RMS voltmeter uses a pair of heating
elements and thermocouples to produce a measurement because it's the
best way to measure the equivalent voltage that would generate the
same amount of heat. There are versions that use other methods but
the thermocouple is generally the closest to the real heating value.




--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[William Sommerwerck]

"Jeff Liebermann" wrote in message
news:67v8c91klphqp0mpaf2c0s4h1qrlsavbgu@4ax.com...

RMS power is quite real. A true-RMS voltmeter uses a pair of heating
elements and thermocouples to produce a measurement because it's
the best way to measure the equivalent voltage that would generate
the same amount of heat. There are versions that use other methods
but the thermocouple is generally the closest to the real heating value.

The heating value of a waveform is the average value of its power, NOT the RMS
value of its power.

Many years ago I sat down and calculated this for a sine wave. I assure you, a
sine wave's average power and its RMS power are not at all the same. RMS
applies ONLY to voltage and current.

 

[Phil Allison]

"dave the dickhead "

"Nutcase Kook" is a pig ignorant pommy cunt


Other than p channel in this case, same for BUZ901P nch
eg BUZ906P 200V, 8A ,datasheet says
"POWER MOSFETS FOR
AUDIO APPLICATIONS"
but also
"FEATURES ... (for use in)
HIGH SPEED SWITCHING ... "


** The Semelab app note makes it pretty clear there is a HUGE difference
between "switching" and audio ( ie lateral) power mosfets.

http://products.semelab-tt.com/pdf/ApplicationNoteAlfet.pdf


Would a powerFET designed solely for high speed switching use and 125W
rating be derated in power handling terms to only 50W say for linear 10
Hz
use. Or secondary oscillation liability if paralleled up devices? or
some
other operational failing in audio use not found with smps say ?


"Figure of Merit" in pulsed applications vs "efficiency" in linear
applications. RMS Power is measured in heating ability v DC.

** Yaaawnnnnnnn - more stupid fucking bullshit !!!!!!!!!!!!!!

One colossal fool asks an idiotic question and even BIGGER fools reply.



..... Phil

 

[Phil Allison]

"William Sommerwerck"

Many years ago I sat down and calculated this for a sine wave. I assure
you, a sine wave's average power and its RMS power are not at all the
same. RMS applies ONLY to voltage and current.

** But even a complete fool like Somerwanker should know that the term "RMS
power" is not meant literally.

It is NOT the RMS value of the instantaneous power level.

In the world of audio, it normally refers to a power measurement done using
the RMS value of a sine wave (or other wave if specified ) voltage delivered
into a known resistive load.

A simple bit of calculus shows that the RMS value of a sine wave to be half
the square root of two ( 0.7071) times its peak value.


..... Phil

 

[Maynard A. Philbrook Jr.]

In article <67v8c91klphqp0mpaf2c0s4h1qrlsavbgu@4ax.com>,
jeffl@cruzio.com says...

On Wed, 1 Jan 2014 06:28:29 -0800, "William Sommerwerck"
grizzledgeezer@comcast.net> wrote:

"dave" wrote in message
news:Mpmdnce3Qvd7g1nPnZ2dnUVZ_rWdnZ2d@earthlink.com...

"Figure of Merit" in pulsed applications vs "efficiency"
in linear applications.

Any (???) device can produce more peak power in pulsed mode than continuous,
because it spends less time in the region where it dissipates the most power.


RMS power is measured in heating ability versus DC.

There is no such thing (other than in a mathematical sense) as RMS power.
Voltage and current can have RMS (root-mean-square) values. Squaring voltage
and dividing by resistance, or squaring current and multiplying by resistance
produces the //average// power.

RMS power is quite real. A true-RMS voltmeter uses a pair of heating
elements and thermocouples to produce a measurement because it's the
best way to measure the equivalent voltage that would generate the
same amount of heat. There are versions that use other methods but
the thermocouple is generally the closest to the real heating value.

I got into his long ago, and all the proclaimed experts came out of the
wood work to say I was wrong. RMS power ratings have been stuck on
equipment as long as I can remember.

Jamie

 

[William Sommerwerck]

Many years ago I sat down and calculated this for a sine wave. I assure
you, a sine wave's average power and its RMS power are not at all the same.
RMS applies ONLY to voltage and current.

** But even a complete fool...

I can't be a complete fool, because on rare occasions you agree with me.

...like Sommerwerck should know that the term "RMS power" is not
meant literally.

He knows nothing of the sort. Just because people say "pressure" when they
mean "force", doesn't mean pressure and force are the same thing.

I see ads proclaiming that an amplifier delivers "125 watts RMS power". No, it
doesn't. There is a perfectly good term for that... "continuous average
power", or perhaps "continuous average sinewave power". This term has a
specific meaning, and it IS NOT the same as RMS power.

 

[Jeff Liebermann]

On Wed, 1 Jan 2014 14:16:52 -0800, "William Sommerwerck"
<grizzledgeezer@comcast.net> wrote:

"Jeff Liebermann" wrote in message
news:67v8c91klphqp0mpaf2c0s4h1qrlsavbgu@4ax.com...

RMS power is quite real. A true-RMS voltmeter uses a pair of heating
elements and thermocouples to produce a measurement because it's
the best way to measure the equivalent voltage that would generate
the same amount of heat. There are versions that use other methods
but the thermocouple is generally the closest to the real heating value.

The heating value of a waveform is the average value of its power, NOT the RMS
value of its power.

Many years ago I sat down and calculated this for a sine wave. I assure you, a
sine wave's average power and its RMS power are not at all the same.
RMS applies ONLY to voltage and current.

Ok, I yield to a higher authority. Heating power is average power:
<http://www.eznec.com/Amateur/RMS_Power.pdf>
However that doesn't stop nearly everyone from specifying RMS power.

So, why do people buy true-RMS voltmeters? If they don't measure
anything useful, why bother?


[Personal drivel: I haven't forgotten about the HP4 parts. I've been
busy. Today was the lost battle of the clutch master cylinder.
Tomorrow will be the forgotten backdated billing for last year.]


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Phil Allison]

"William Sommerwanker = IDIOT"

Many years ago I sat down and calculated this for a sine wave. I assure
you, a sine wave's average power and its RMS power are not at all the
same. RMS applies ONLY to voltage and current.

** But even a complete fool...

I can't be a complete fool,

** Yes you are and about to prove it yet again.

...like Sommerwerck should know that the term "RMS power" is not
meant literally.

He knows nothing of the sort.

** Proof given

I see ads proclaiming that an amplifier delivers "125 watts RMS power".
No, it doesn't.

** " ... the term "RMS power" is not meant literally."

Cos it is not what the writer meant PLUS there is simply no such quantity
if you do.

FUCKWIT !!!!!!!!!!!!


..... Phil

 

[Phil Allison]

"Jeff Liebermann"

Ok, I yield to a higher authority. Heating power is average power:
http://www.eznec.com/Amateur/RMS_Power.pdf
However that doesn't stop nearly everyone from specifying RMS power.

** There is no such quantity as " RMS power " if you are so stupid as to
interpret the term literally.

> So, why do people buy true-RMS voltmeters?

** To get " true RMS " volts of course.

If they don't measure anything useful,

** The RMS value of a voltage or current could hardly be more useful.

My god, you are SOOOOOO illiterate and SOOOOO retarded.




.... Phil

 

[Phil Allison]

"Jeff Liebermann"

Ok, I yield to a higher authority. Heating power is average power:
http://www.eznec.com/Amateur/RMS_Power.pdf
However that doesn't stop nearly everyone from specifying RMS power.

** There is no such quantity as " RMS power " if you are so stupid as
to
interpret the term literally.

Which term should be interpreted non-literally?

** The term " RMS power " of course -

you fucking BLIND nut case ASSHOLE !!!!!!!!!!!!
----------------------------------------------------------

So, why do people buy true-RMS voltmeters?

** To get " true RMS " volts of course.

Very good. But since there doesn't seem to be any correlation with
heating power (despite using a thermocouple to do the measuring) and
RMS volts or watts,

** Quite wrong - there is a very close connection.

what does the meter indication on a true RMS
voltmeter actually mean? Or is it just a mathematical abstraction?

** RMS voltage or current value = the DC equivalent value.

So the DC power formulas: " I squared R " and " V squared / R "
still apply in power calculations using AC voltages & currents.
---------------------------------------------------------------------------



** The RMS value of a voltage or current could hardly be more useful.

My god, you are SOOOOOO illiterate and SOOOOO retarded.

Very perceptive and partly true.

** It's completely true.

You are the stupidest, most retarded, constantly lying fuckwit on the NG.

Get cancer and fucking DIE !



..... Phil

 

[Jeff Liebermann]

On Thu, 2 Jan 2014 13:00:20 +1100, "Phil Allison" <phil_a@tpg.com.au>
wrote:

"Jeff Liebermann"

Ok, I yield to a higher authority. Heating power is average power:
http://www.eznec.com/Amateur/RMS_Power.pdf
However that doesn't stop nearly everyone from specifying RMS power.

** There is no such quantity as " RMS power " if you are so stupid as
to
interpret the term literally.

Which term should be interpreted non-literally?

** The term " RMS power " of course -

I thought you meant term as in the terms of an equation, where term
refers to the individual parts of the equation, not the whole. In the
same way, I use "term" to describe a single word, not a phrase. I
suggest you amend your proclamation by replacing the word "term" with
"phrase" as in:
"** There is no such quantity as " RMS power " if you
are so stupid as to interpret the phrase literally."

> you fucking BLIND nut case ASSHOLE !!!!!!!!!!!!

Yeah, I know. My eyesight is a problem and my hemorrhoids are driving
me nuts.

Very good. But since there doesn't seem to be any correlation with
heating power (despite using a thermocouple to do the measuring) and
RMS volts or watts,

** Quite wrong - there is a very close connection.

<http://www.eznec.com/Amateur/RMS_Power.pdf>
On Pg 6 it says:
"The RMS value of power is not the equivalent heating power and,
in fact, it doesn't represent any useful physical quantity."
and:
"The RMS power is different than the average power, and therefore
isn’t the equivalent heating power. In fact, the RMS value of the
power doesn’t represent anything useful."

It would seem that the author finds average power different from, more
useful than, and closer to heating power. Perhaps we should change
the name from "true-RMS voltmeter" to "true heating average
voltmeter"?

"So it is written, so it shall be."
(Ramses in the CB DeMille version of the 10 Commandments).

(...)

You are the stupidest, most retarded, constantly lying fuckwit on the NG.
Get cancer and fucking DIE !

You'll not get rid of me that easily. I've already had cancer and
Obamacare promises to keep me alive forever.


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Phil Allison]

"Jeff Liebermann = retarded asshole "

Ok, I yield to a higher authority. Heating power is average power:
http://www.eznec.com/Amateur/RMS_Power.pdf
However that doesn't stop nearly everyone from specifying RMS power.

** There is no such quantity as " RMS power " if you are so stupid as
to
interpret the term literally.

Which term should be interpreted non-literally?

** The term " RMS power " of course -

I thought ...

** No you didn't - cos you are incapable of thought.

The quotation marks made my words quite *impossible* to misinterpret.

Very good. But since there doesn't seem to be any correlation with
heating power (despite using a thermocouple to do the measuring) and
RMS volts or watts,

** Quite wrong - there is a very close connection.

( snip more TOTALLY IRRELEVANT SHIT )

Leiberman - you are the stupidest, most retarded, constantly lying fuckwit
on the NG.

Get cancer and fucking DIE !

 

[Jeff Liebermann]

On Thu, 2 Jan 2014 13:56:15 +1100, "Phil Allison" <phil_a@tpg.com.au>
wrote:

I thought ...

** No you didn't - cos you are incapable of thought.

"I am, therefore I think". (My apologies to Descartes).
My presence always inspires thought.

> The quotation marks made my words quite *impossible* to misinterpret.

The contradiction between your quoted phrase and the misuse of the
word "term" makes it quite easy to misinterpret, which is why I asked
for clarification.

>( snip more TOTALLY IRRELEVANT SHIT )

Hardly. I cited an excellent analysis of the misuse of the phrase
"RMS power" to demonstrate my point and this is the best response that
you can offer? Surely, you can do better. Incidentally, go easy on
the overuse of spaces between words. The worlds supply of blank space
is limited. If depleted, will cause allthewordstoruntogether.

Leiberman - you are the stupidest, most retarded, constantly lying fuckwit
on the NG.

Is there some significance to the creative spelling of my last name?
Perhaps your are referring to someone else? Or are you simply
incapable of spelling my name twice the same manner? I shall ponder
the meaning of this obviously intentional creative spelling while I
take out the garbage and sort through the recycling. Surely, that
will inspire enlightenment.

Also, I would appreciate it if you would be a bit more creative in
your insults. Australia is famous for it's colorful insults, an
ability which you seem to be deficient. Perhaps these links will help
improve your vocabulary:
<http://www.youswear.com/index.asp?language=Australian>
<http://www.koalanet.com.au/australian-slang.html>
<http://en.wiktionary.org/wiki/Appendix:Australian_English_terms_for_people>
Unfortunately, I consider your spelling, formatting, capitalization,
grammar, and punctuation to be hopeless and beyond redemption. No
amount of remedial practice will help. I suggest you give up and hire
either a proof reader or a ghost writer. (No, you can't have mine).

>Get cancer and fucking DIE !

Sorry, but I've already had (prostate) cancer and failed to drop dead
in your requested manner. Obviously something is wrong with your
recommended procedure. Perhaps you could be a little more specific?



--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558