M
Michael A. Terrell
Guest
o pere o wrote:
Wow! Were did you find 2N222s? Obsolete for decades, and damn
expensive.
Wow! Were did you find 2N222s? Obsolete for decades, and damn
expensive.
J
Jim Thompson
Guest
On Mon, 12 Nov 2012 16:02:51 -0500, legg <legg@nospam.magma.ca> wrote:
model...
http://www.analog-innovations.com/SED/BipolarTransistor_FromPSPCREF.pdf
NOT a trivial model ;-)
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice
480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Gummel-Poon, particularly as implemented in Spice, IS a non-linearOn Mon, 12 Nov 2012 12:41:46 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:
On Mon, 12 Nov 2012 14:22:48 -0500, legg <legg@nospam.magma.ca> wrote:
On Mon, 12 Nov 2012 09:55:50 +0100, o pere o <me@somewhere.net> wrote:
snip
The 2n2222a model may be missing (from inspection of popular models)
ISC, VJE, VJC, VJS, XCJC, FC, MJE, MJC, MJS, ITF, VTF, XTF.
snip
Everyone has their own idea, see below, based on a variety of amateur
(usually a know-it-all PhD
snip
...Jim Thompson
All those models have the same problem w/r to reverse emitter current
at 25MHz.
Looks like CJE is four orders of magnitude higher than BFR93a or
BFP405.
Correcting this on any of the 2n2222 models fixes it, but I'm not sure
how an emitter junction could be expected to exhibit capacitance in
the 1E-15 range.
RL
Well, I have been using a 2N222s model with Cje=22 pF. The BFR93 gives
2pF, i.e. one order of magnitude less and the BFP 405 gives 3.7 fF.
Now it is about time to make some measurements...
Pere
There is also an issue with CJC, in combination with RB, that defines
the delay and speed of the falling edge of the emitter-follower
rectifier. Capacitance with the same orders of magnitude difference
show up, producing a spike, if significant.
Gummel-Poon BJT modeling is aimed at small-signal representations,
where DC-biased variables are roughly static (even if non-linear).
I've seen this combated with look-up tables, but it's slooooow.
Wrong. If you properly extract all the parameters it correctly models
everything but deep saturation and injection into substrate. PSpice
adds the ability to model that region (used to be useful in TTL days
;-); and also provides an alternate model, MEXTRAM.
Could you identify the parameters that ensure this accuracy?
Does it include any of those presently missing?
RL
model...
http://www.analog-innovations.com/SED/BipolarTransistor_FromPSPCREF.pdf
NOT a trivial model ;-)
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice
480)460-2350 Fax: Available upon request | Brass Rat || E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Guest
On Mon, 12 Nov 2012 18:40:59 -0500, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:
<mike.terrell@earthlink.net> wrote:
Come on! In the Spice catalog, they're really cheap!
M
Michael A. Terrell
Guest
krw@att.bizzz wrote:
They were never 'cheap'.
They were never 'cheap'.
Guest
On Mon, 12 Nov 2012 20:09:47 -0500, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:
<mike.terrell@earthlink.net> wrote:
The Spice ones are. You can't get much cheaper than LTSpice.
T
Tim Williams
Guest
<krw@att.bizzz> wrote in message
news:nk83a8513e050ep4vghu42121moo51js29@4ax.com...
https://www.google.com/search?q=2n222+spice+-2n2222
http://alltransistors.com/transistor.php?transistor=1764
Methinks the SPICE catalog says "Please Call".
Tim
--
Deep Friar: a very philosophical monk.
Website: http://seventransistorlabs.com
news:nk83a8513e050ep4vghu42121moo51js29@4ax.com...
You sure?
https://www.google.com/search?q=2n222+spice+-2n2222
http://alltransistors.com/transistor.php?transistor=1764
Methinks the SPICE catalog says "Please Call".
Tim
--
Deep Friar: a very philosophical monk.
Website: http://seventransistorlabs.com
M
Michael A. Terrell
Guest
krw@att.bizzz wrote:
You have spice models for '60s vintage three digit transistors?
You have spice models for '60s vintage three digit transistors?
O
o pere o
Guest
On 11/12/2012 07:37 PM, legg wrote:
http://www.nxp.com/download/pip/BFR93A/models : + CJE =
2.03216E-012
Could you post your whole model, to check if there are more differences?
Pere
Strange, I got it directly from NXPOn Mon, 12 Nov 2012 09:55:50 +0100, o pere o <me@somewhere.net> wrote:
On 11/12/2012 03:34 AM, legg wrote:
On Sun, 11 Nov 2012 12:17:22 -0500, legg <legg@nospam.magma.ca> wrote:
On Sat, 10 Nov 2012 22:53:08 +0100, o pere o <me@somewhere.net> wrote:
To make a long story short, I ended up simulating an emitter follower
with Qucs. This simulator has some transistor models embedded, but you
are able to insert PSpice models and subcircuits if you need more.
When you increase input signal level up to the point where the output
should clip at zero, one transistor model clips correctly (BFP405, from
Qucs) but others not (BFR93a, 2N2222A). The BFR93a model is a PSpice
model from the NXP site and I have tried several 2N2222a models (one
from Qucs itself, one PSpice model from Zetex and another PSpice model
from somewhere): none of these clips at zero although it does at VCC=3.3.
Tried the same circuit in LTSpice with the same result. Am I the only
one experiencing this? Has anyone got better large-signal models
-especially for the BFR93a?
Pere
At 25MHz, your input signal is using the bipolar transistor as
rectifier, clamped by the CB junction.
You'd need a lot of accurate reverse and dynamic parameters in your
model, to get anything close to reality.
The 2n2222a model may be missing (from inspection of popular models)
ISC, VJE, VJC, VJS, XCJC, FC, MJE, MJC, MJS, ITF, VTF, XTF.
At 25MHz, your input signal is using the bipolar transistor as
rectifier, clamped by the CB junction.
You'd need a lot of accurate reverse and dynamic parameters in your
model, to get anything close to reality.
ISC, VJE, VJC, VJS, XCJC, FC, MJE, MJC, MJS, ITF, VTF, XTF.
RL
Everyone has their own idea, see below, based on a variety of amateur
(usually a know-it-all PhD
snip
...Jim Thompson
All those models have the same problem w/r to reverse emitter current
at 25MHz.
Looks like CJE is four orders of magnitude higher than BFR93a or
BFP405.
Correcting this on any of the 2n2222 models fixes it, but I'm not sure
how an emitter junction could be expected to exhibit capacitance in
the 1E-15 range.
RL
Well, I have been using a 2N222s model with Cje=22 pF. The BFR93 gives
2pF, i.e. one order of magnitude less and the BFP 405 gives 3.7 fF.
Now it is about time to make some measurements...
Pere
BFR93a in the file I have has CJE of 3.2E-15, similar to BFP405. If
this is altered to 2.2pF, an emitter excursion to -2.5V occurs.
RL
http://www.nxp.com/download/pip/BFR93A/models : + CJE =
2.03216E-012
Could you post your whole model, to check if there are more differences?
Pere
O
o pere o
Guest
On 11/13/2012 12:40 AM, Michael A. Terrell wrote:
And Farnell still has them on stock (from
several manufacturers...:
http://es.farnell.com/stmicroelectronics/2n2222a/transistor-npn-40v-0-6a-to18/dp/9801278
http://es.farnell.com/multicomp/2n2222a/bipol-transistor-npn-to-18-40v/dp/9207120
etc.
BTW, the interesting measurements are not on the 2N2222...
Pere
I still have some of them
And Farnell still has them on stock (from several manufacturers...:
http://es.farnell.com/stmicroelectronics/2n2222a/transistor-npn-40v-0-6a-to18/dp/9801278
http://es.farnell.com/multicomp/2n2222a/bipol-transistor-npn-to-18-40v/dp/9207120
etc.
BTW, the interesting measurements are not on the 2N2222...
Pere
O
o pere o
Guest
On 11/13/2012 10:33 AM, o pere o wrote:
Pere
Ooops, seems that I missed one of the "2" on my post. Didn't get it on time!On 11/13/2012 12:40 AM, Michael A. Terrell wrote:
o pere o wrote:
Well, I have been using a 2N222s model with Cje=22 pF. The BFR93 gives
2pF, i.e. one order of magnitude less and the BFP 405 gives 3.7 fF.
Now it is about time to make some measurements...
Wow! Were did you find 2N222s? Obsolete for decades, and damn
expensive.
I still have some of them
several manufacturers...:
http://es.farnell.com/stmicroelectronics/2n2222a/transistor-npn-40v-0-6a-to18/dp/9801278
http://es.farnell.com/multicomp/2n2222a/bipol-transistor-npn-to-18-40v/dp/9207120
etc.
BTW, the interesting measurements are not on the 2N2222...
Pere
Pere
L
legg
Guest
On Tue, 13 Nov 2012 10:26:30 +0100, o pere o <me@somewhere.net> wrote:
Philips in 1995......BFR91A was SOT37. Same die.
Check out the Seimens model, though:
http://www.dl2jwl.de/pdf/bfr93a.pdf
These are the values used in the LTspice distro.
I would like to see the Telefunken file, if there ever was one, but
Vishay seems to have divested it's bipolar semiconductors entirely,
since having 'incorporated' their ass.
RL
Actually a BFR91A model, relabelled BFR93A, in an SOT23 package fromOn 11/12/2012 07:37 PM, legg wrote:
On Mon, 12 Nov 2012 09:55:50 +0100, o pere o <me@somewhere.net> wrote:
On 11/12/2012 03:34 AM, legg wrote:
On Sun, 11 Nov 2012 12:17:22 -0500, legg <legg@nospam.magma.ca> wrote:
On Sat, 10 Nov 2012 22:53:08 +0100, o pere o <me@somewhere.net> wrote:
To make a long story short, I ended up simulating an emitter follower
with Qucs. This simulator has some transistor models embedded, but you
are able to insert PSpice models and subcircuits if you need more.
When you increase input signal level up to the point where the output
should clip at zero, one transistor model clips correctly (BFP405, from
Qucs) but others not (BFR93a, 2N2222A). The BFR93a model is a PSpice
model from the NXP site and I have tried several 2N2222a models (one
from Qucs itself, one PSpice model from Zetex and another PSpice model
from somewhere): none of these clips at zero although it does at VCC=3.3.
Tried the same circuit in LTSpice with the same result. Am I the only
one experiencing this? Has anyone got better large-signal models
-especially for the BFR93a?
Pere
At 25MHz, your input signal is using the bipolar transistor as
rectifier, clamped by the CB junction.
You'd need a lot of accurate reverse and dynamic parameters in your
model, to get anything close to reality.
The 2n2222a model may be missing (from inspection of popular models)
ISC, VJE, VJC, VJS, XCJC, FC, MJE, MJC, MJS, ITF, VTF, XTF.
At 25MHz, your input signal is using the bipolar transistor as
rectifier, clamped by the CB junction.
You'd need a lot of accurate reverse and dynamic parameters in your
model, to get anything close to reality.
ISC, VJE, VJC, VJS, XCJC, FC, MJE, MJC, MJS, ITF, VTF, XTF.
RL
Everyone has their own idea, see below, based on a variety of amateur
(usually a know-it-all PhD
snip
...Jim Thompson
All those models have the same problem w/r to reverse emitter current
at 25MHz.
Looks like CJE is four orders of magnitude higher than BFR93a or
BFP405.
Correcting this on any of the 2n2222 models fixes it, but I'm not sure
how an emitter junction could be expected to exhibit capacitance in
the 1E-15 range.
RL
Well, I have been using a 2N222s model with Cje=22 pF. The BFR93 gives
2pF, i.e. one order of magnitude less and the BFP 405 gives 3.7 fF.
Now it is about time to make some measurements...
Pere
BFR93a in the file I have has CJE of 3.2E-15, similar to BFP405. If
this is altered to 2.2pF, an emitter excursion to -2.5V occurs.
RL
Strange, I got it directly from NXP
http://www.nxp.com/download/pip/BFR93A/models : + CJE =
2.03216E-012
Could you post your whole model, to check if there are more differences?
Pere
Philips in 1995......BFR91A was SOT37. Same die.
Check out the Seimens model, though:
http://www.dl2jwl.de/pdf/bfr93a.pdf
These are the values used in the LTspice distro.
I would like to see the Telefunken file, if there ever was one, but
Vishay seems to have divested it's bipolar semiconductors entirely,
since having 'incorporated' their ass.
RL
L
legg
Guest
On Tue, 13 Nov 2012 10:59:50 -0500, legg <legg@nospam.magma.ca> wrote:
It looks like the Siemens spice model has a typo fF for pF. There's no
way CJC could be three orders of magnitude larger than CJE in the same
part.
RL
The last Telefunken (Temic) datasheet for bfr93 lists S parameters.
It looks like the Siemens spice model has a typo fF for pF. There's no
way CJC could be three orders of magnitude larger than CJE in the same
part.
RL
J
Jim Thompson
Guest
On Tue, 13 Nov 2012 13:08:57 -0500, legg <legg@nospam.magma.ca> wrote:
library)...
..SUBCKT BFR93A
Q1 6 5 7 7 BFR91A
* SOT23 parasitic model
Lb 4 5 .4n
Le 7 8 .83n
L1 2 4 .35n
L2 1 6 .17n
L3 3 8 .35n
Ccb 4 6 71f
Cbe 4 8 71f
*
* PHILIPS SEMICONDUCTORS Version: 1.0
* Filename: BFR91A.PRM Date: Feb 1992
*
..MODEL BFR91A NPN
+ IS = 1.32873E-015
+ BF = 1.02000E+002
+ NF = 1.00025E+000
+ VAF = 5.19033E+001
+ IKF = 8.15511E+000
+ ISE = 1.39029E-014
+ NE = 1.51292E+000
+ BR = 1.76953E+001
+ NR = 9.94038E-001
+ VAR = 3.28032E+000
+ IKR = 1.00000E+001
+ ISC = 1.04297E-015
+ NC = 1.18993E+000
+ RB = 1.00000E+001
+ IRB = 1.00000E-006
+ RBM = 1.00000E+001
+ RE = 7.63636E-001
+ RC = 9.00000E+000
+ EG = 1.11000E+000
+ XTI = 3.00000E+000
+ CJE = 2.03216E-012
+ VJE = 6.00000E-001
+ MJE = 2.90076E-001
+ TF = 6.55790E-012
+ XTF = 3.89752E+001
+ VTF = 1.09308E+001
+ ITF = 5.21078E-001
+ CJC = 1.00353E-012
+ VJC = 3.40808E-001
+ MJC = 1.94223E-001
..ENDS
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Here's what I have (from a Kevin Alyward - SuperSpice/Anasoft/Philips
library)...
..SUBCKT BFR93A
Q1 6 5 7 7 BFR91A
* SOT23 parasitic model
Lb 4 5 .4n
Le 7 8 .83n
L1 2 4 .35n
L2 1 6 .17n
L3 3 8 .35n
Ccb 4 6 71f
Cbe 4 8 71f
*
* PHILIPS SEMICONDUCTORS Version: 1.0
* Filename: BFR91A.PRM Date: Feb 1992
*
..MODEL BFR91A NPN
+ IS = 1.32873E-015
+ BF = 1.02000E+002
+ NF = 1.00025E+000
+ VAF = 5.19033E+001
+ IKF = 8.15511E+000
+ ISE = 1.39029E-014
+ NE = 1.51292E+000
+ BR = 1.76953E+001
+ NR = 9.94038E-001
+ VAR = 3.28032E+000
+ IKR = 1.00000E+001
+ ISC = 1.04297E-015
+ NC = 1.18993E+000
+ RB = 1.00000E+001
+ IRB = 1.00000E-006
+ RBM = 1.00000E+001
+ RE = 7.63636E-001
+ RC = 9.00000E+000
+ EG = 1.11000E+000
+ XTI = 3.00000E+000
+ CJE = 2.03216E-012
+ VJE = 6.00000E-001
+ MJE = 2.90076E-001
+ TF = 6.55790E-012
+ XTF = 3.89752E+001
+ VTF = 1.09308E+001
+ ITF = 5.21078E-001
+ CJC = 1.00353E-012
+ VJC = 3.40808E-001
+ MJC = 1.94223E-001
..ENDS
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice
480)460-2350 Fax: Available upon request | Brass Rat || E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
O
o pere o
Guest
Ok, so I tested this
C-----*-----3.3V
Gen--50R---B |
E 10nF
| |
1k gnd
|
gnd
measuring Vb and Ve. Transistors: 2N2222a and BFR93a.
BFR93a:
Generator is adjusted to Vdc=2.3V and 5Vpp.
At 1 MHz, the emitter signal waveform is a nice trapezoidal signal with
a steeper slope when leaving the upper clipping level. The simulator
predicts rounded tops and a somewhat upwards sloping bottom.
At 27 MHz the Spice model predicts negative signal excursions. I could
not observe them. But if I add some 5-10 pF at the emitter resistance to
account for the probe, simulations and reality almost match.
2N2222a:
Generator is adjusted to Vdc=0 and 5Vpp.
At 27 MHz, Spice model predicts sinusoidal signal centered around 0
approx +-2.3. On the scope I see max +1.8 and min -1.5, i.e. there is
some loss but the qualitative shape is ok. Of course, this is not what
the circuit is expected to do, but indicates the model is ok.
At 1 MHz, Spice model predicts bottom clipping but with positive slope
of 1.9V/us. Measurements more or less confirm this.
At 27 MHz, a quite sinusoidal output signal of 4Vpp can be measured
adjusting Vdc=1.3. The simulator predicts the same, although with a
4.5Vpp amplitude. So, the model seems ok.
Conclusion:
The Spice models are ok and they do model large signal behavior. It was
my error to assume that there could be no negative signal excursions:
this is only true at low frequencies. Somehow I thought that 27 MHz was
dc for a 5 GHz transistor. But his is not the case for a high input
impedance circuit, as JT pointed out.
Thanks to all.
Pere
L
legg
Guest
On Tue, 13 Nov 2012 12:07:58 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:
This is the same Philips model listed in the LTspice group comparison,
and currntly offered for download from NXP, though a later date is
attributed to the file:
http://tech.groups.yahoo.com/group/LTspice/files/%20Lib/BFR93A/
A ring oscillator sim is offered for 4 model versions.
If the Siemens/Infineon model's CJE is altered from xE-15 to xE-12,
it's performance more closely resembles the other three versions, in
simulation.
RL
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:
This is the same Philips model listed in the LTspice group comparison,
and currntly offered for download from NXP, though a later date is
attributed to the file:
http://tech.groups.yahoo.com/group/LTspice/files/%20Lib/BFR93A/
A ring oscillator sim is offered for 4 model versions.
If the Siemens/Infineon model's CJE is altered from xE-15 to xE-12,
it's performance more closely resembles the other three versions, in
simulation.
RL
Guest
On Mon, 12 Nov 2012 22:38:52 -0600, "Tim Williams"
<tmoranwms@charter.net> wrote:
anything for mine.
<tmoranwms@charter.net> wrote:
I don't know what your problem is (understatement) but I didn't pay
anything for mine.
T
Tim Williams
Guest
<krw@att.bizzz> wrote in message
news:3clca816h9bu91k6j0c84e4d03t3ij5guk@4ax.com...
three-digit 2N222, not the 2N2222.
Do SPICE models even exist for any pure-Ge (not SiGe) transistors???
Tim
--
Deep Friar: a very philosophical monk.
Website: http://seventransistorlabs.com
news:3clca816h9bu91k6j0c84e4d03t3ij5guk@4ax.com...
Did you look at the links I posted?? We were talking about the
three-digit 2N222, not the 2N2222.
Do SPICE models even exist for any pure-Ge (not SiGe) transistors???
Tim
--
Deep Friar: a very philosophical monk.
Website: http://seventransistorlabs.com
L
legg
Guest
On Mon, 12 Nov 2012 16:45:06 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:
http://www.nxp.com/wcm_documents/models/bipolar-models/mextram/nlur2002823.pdf
RL
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:
Some info on the Mextram model.
http://www.nxp.com/wcm_documents/models/bipolar-models/mextram/nlur2002823.pdf
RL
M
miso
Guest
No thanks. I do not want to contribute $3 to the "Death to America"
fund. But thanks for asking.
fund. But thanks for asking.
R
Robert Baer
Guest
Fred Abse wrote:
ONLY, i have determined that pickup of external signals (hum and related
bazz-fazz), having the floating shield is a bit better than not having
it at all.
The negative of that is, getting pinkies close to that shield does
severely compromise the risetime & undershoot of the probe.
Concerning the "development" of the two 1G internally terminated
probe, each of those resistors seem to be too long and pickup becomes
intolerable, and a floating shield might have to be referred to ground
(maybe a resistor).
It also looks like a multiple pi-pad model is not the best for
modelling these resistors..
Concerning the original Q&D probe where the scope must be DC coupled
ONLY, i have determined that pickup of external signals (hum and related
bazz-fazz), having the floating shield is a bit better than not having
it at all.
The negative of that is, getting pinkies close to that shield does
severely compromise the risetime & undershoot of the probe.
Concerning the "development" of the two 1G internally terminated
probe, each of those resistors seem to be too long and pickup becomes
intolerable, and a floating shield might have to be referred to ground
(maybe a resistor).
It also looks like a multiple pi-pad model is not the best for
modelling these resistors..