Kevin McMurtrie <mcmurtri@dslextreme.com> wrote in
news:mcmurtri-A3D31B.22241102062005@corp-radius.supernews.com:

> In article <Xns96699C7F9EAA2tegger@207.14.113.17>,
> "TeGGeR®" <tegger@tegger.c0m> wrote:
>

>> I'm having trouble getting my mind around this.
>>
>> I am aware that "flow" is _commonly_ considered to be from the
>> positive to negative terminals of the battery, but the electrons
>> themselves go in the OTHER direction.
>
> Most materials have an electron flow, which goes from negative to
> positive. I've heard that some materials can have a proton flow.
> Both may exist in a vacuum.
>
> Current flow arrows on diagrams go from positive to negative.
>
> Bipolar transistors are current amplifiers. When a current flows
> through the base-emitter diode junction, a stronger current is allowed
> to flow from the collector to the emitter.



So then my diagrams are correct. I assumed the base electrode to act as the
switch, turning power on and off between the collector and the emitter.

Thanks.






--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

 

Kevin McMurtrie wrote:
> In article <Xns96699C7F9EAA2tegger@207.14.113.17>,
> "TeGGeR®" <tegger@tegger.c0m> wrote:
>
>
>>Jim Yanik <jyanik@abuse.gov.> wrote in
>>news:Xns966963506AD29jyanikkuanet@129.250.170.86 :
>>
>>
>>>"TeGGeR®" <tegger@tegger.c0m> wrote in
>>>news:Xns9668EF412B3E6tegger@207.14.113.17:
>>>
>>>
>>>>Randolph <trash@junkmail.com> wrote in
>>>>news:429D4577.2B7930FB@junkmail.com:
>>>>
>>>>
>>>>>The
>>>>>data sheet shows the diode between emitter and collector.
>>>>
>>>>
>>>>So then it wouldn't make much sense to try and show it.
>>>>
>>>>Randolph, I'm having trouble understanding the current path through
>>>>the transistor. I found this page:
>>>>http://nobelprize.org/physics/educat...nction/thegame.
>>>>h tml
>>>>
>>>>It helps me understand more, but I don't get which way the current
>>>>goes through the base electrode. I have a suspicion that my diagrams
>>>>show the current going the wrong way through the transistor.
>>>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>>>
>>>>
>>>>
>>>
>>>There's two current paths;the B-E path and the C-E path(main path).
>>>Current flows the opposite direction of the emitter arrow,for both
>>>base and collector currents.
>>>
>>
>>
>>I'm having trouble getting my mind around this.
>>
>>I am aware that "flow" is _commonly_ considered to be from the positive to
>>negative terminals of the battery, but the electrons themselves go in the
>>OTHER direction.
>
>
> Most materials have an electron flow, which goes from negative to
> positive. I've heard that some materials can have a proton flow.

don't get no proton flow unless you're into nuclear chemistry. in
semiconductors, conduction is by way of negative electrons & positive
"holes". you /can/ have [positive] ions move in the semiconductor
lattice, but they are not a part of the primary conduction mechanism &
result in mass transport & therefore degradation of the semiconductor -
they are not a proton thing.

> Both
> may exist in a vacuum.
>
> Current flow arrows on diagrams go from positive to negative.
>
> Bipolar transistors are current amplifiers. When a current flows
> through the base-emitter diode junction, a stronger current is allowed
> to flow from the collector to the emitter. The C-E junction is .2 to .4
> volts when the B-E junction is saturated (~.65 V). The current gain for
> a power transistor is usually 10 to 100. Darlington pairs have that
> gain squared. Gains are not at all consistent so they're usually
> specified as a range.
>
> MOSFETs are tiny voltage controlled amplifiers. Absolutely zero static
> current is required to turn them on or off; just the capacitance
> current. Because of their infinite current gain, millions may be
> paralleled on a single chip to satisfy any current load. Their voltage
> gain is very low - a typical gate threshold voltage is 4V and a typical
> gate saturation voltage is 10V. There's no voltage drop between the
> source and drain, only resistance. High voltage capability makes each
> MOSFET junction larger and dramatically increases resistance.
>
> IGBTs are similar to bipolar transistors but with an insulated gate like
> a MOSFET. They have the high voltage capacity of bipolars but need no
> driving current like a MOSFET. They're very slow so they're usually
> limited to controlling industrial motors. (Honda hybrid cars use them
> for their motors.)
>
>
>
>>http://www.tegger.com/hondafaq/ignit...ion/index.html
>>http://www.tegger.com/hondafaq/ignit...adigniter.html
>>On these two pages, is the current flow through the transistors correctly
>>depicted? Nobody has answered that question yet.

 

"TeGGeR®" <tegger@tegger.c0m> wrote in
news:Xns9669D79281ACtegger@207.14.113.17:

> Jim Yanik <jyanik@abuse.gov.> wrote in
> news:Xns9669BF9265BD5jyanikkuanet@129.250.170.83:
>
>
>>>
>>
>> The electrons are what's doing the moving,and they flow from neg to
>> pos.
>>
>
>
> The electrons flow from POSITIVE TO NEGATIVE. The electrons go from
> where they are (-) to where they're not: The "holes" (+).
> http://nobelprize.org/physics/educat...tion/forward.h
> tml
>
> It's the actual everyday signal that's commonly perceived to go from
> negative to positive.
>
> But we have THREE paths in a transistor ("transfer resistor"). For a
> non- techie, this is non-intuitive. I do not get how TWO terminals can
> have THREE paths.

think of a Y water pipe.One arm of the Y is smaller than the other.But the
total water flow thru the bottom of the Y divides and part passes thru the
left arm and part thru the right arm.You can control how much water passes
thru the right arm by adjusting the flow thru the left arm.(but the water
pipe does not have any current gain)

>
> Please try to understand that I am not trying to be difficult, but
> that this is not at all making sense to me.
>
> I am hoping that someone, somewhere, will post with an explanation
> that makes sense to my mind. In my professional life I have taught and
> trained many, many individuals, and most have had certain things that
> just would not "click" until the information was presented a certain
> way. I am seeking that way, and I will persist until I find it. This
> is driving me crazy.
>
> This graphic:
> http://nobelprize.org/physics/educat...tion/amplifica
> tion .html
> (all on one line; copy-and-paste as necessary)
> shows the signal path from base electrode to collector.
>
> This one:
> http://nobelprize.org/physics/educat...tion/pointsymb
> ol.h tml
> (again, all on one line)
> appears to show the path from emitter to collector.
>
> I do not get this and I am trying madly to understand. Graham W would
> be able to correct me in an instant. He has been the most persnicketly
> critical observer and the most productive from my point of view.
> Graham, where aaaaaare you?...
>
> Graham was the ONLY one to suggest alterations to the Main Relay
> function graphics. Graham was the ONLY one to inform me of certain
> HTML errors, the correction of which make it easier for browsers to
> display the intended information.
>
> Ah, but wait. I just thought of something: alt.electronics. Back
> soon...
>

Just think of a vacuum tube;the cathode(negative terminal) is heated so it
will emit *electrons*,which are attracted to the positively charged anode
plate,thus;ELECTRON FLOW,from negative to positive.

--
Jim Yanik
jyanik
at
kua.net

 

Jim Yanik wrote:
>
> Randolph <trash@junkmail.com> wrote in news:429D4577.2B7930FB@junkmail.com:

> > See
> > http://www.st.com/stonline/books/ascii/docs/5288.htm for details. The
> > data sheet is at http://www.st.com/stonline/books/pdf/docs/5288.pdf. The
> > data sheet shows the diode between emitter and collector.
>
> The diode is INTERNAL to the transistor package.
> Probably on the same substrate as the xstr.

Yes, that is what I meant, and that is what the data sheet shows.

> > The IC in the photo looks like it has part number U2226B, and a good
> > guess is that the TFK in the first line stand for Telefunken, a German
> > semiconductor manufacturer later renamed TEMIC and eventually bought by
> > Vishay. I have not found any data sheet for the U2226B, but I believe it
> > is an opto-coupler.
> >
>
> I found ICs that were specifically designed for ignition control and
> driving the Darlingtons,but none with the same pin count of the IC
> pictured,nor any similarity to its part number.
> I do not believe it's an optocoupler,but a full control IC.Probably with
> circuitry to square up(shape) the drive pulse,and provide enough drive
> current,and IIRC,the ICs monitored and regulated coil current.(that would
> enable faster switching)

I did some more digging, and you are right, it is not an opto-coupler.
It is indeed a chip for controlling ignition coils. It is made by
Telefunken / TEMIC, and they had a family of 3: U2225B is used when the
input is from an inductive sensor, U2226B is intended for use with a
microcontroller / microprocessor and U2227B is used when the chip is
connected directly to an optical sensor. I have not had any luck finding
the data sheet for this part.

 

Jim Yanik <jyanik@abuse.gov.> wrote in
news:Xns966B7FE54E0Fjyanikkuanet@129.250.170.84:


<snip>

>> That was how Jim got into the semantic trap to start with. The ECU
>> supplies a low current ground to pin 4, which grounds an input on the
>> IC, but the main ground - the one the coil current flows through - is
>> the one shown in the lower right corner of the ignitor; the metal body
>> of the ignitor itself. The current from pin 4 is undoubtedly in the
>> range of 1 ma.
>>
>> Mike
>>
>>
>>
>
> Yes,the ECU signal is a normally HI,LO(ground)-to-enable signal.
>


I've removed the innards of the igniter from the graphics and will add that
body round later on, changing the yellow and orange lines around to suit.
http://www.tegger.com/hondafaq/ignit...ion/index.html

Since the workings are far more detailed than I had originally imagined, I
will leave the igniter as a "here be dragons" blank box until somebody else
decides to supply a correct schematic for me to copy.

Thanks very much to all.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/