Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| 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.

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?




--

John Larkin Highland Technology, Inc

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

On 17/06/2014 20:02, John Larkin wrote:
On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

I would hope to see some electrical behaviour!

--
Mike Perkins
Video Solutions Ltd
www.videosolutions.ltd.uk

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| 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.

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| 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.

Jim Thompson wrote:
On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson
Attached is an old Infineon lib of FETs, etc that may be of use.

Jim Thompson wrote:
On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson
Fairchild FQD2N100 model attached.

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.

You didn't notice the discontinuities?

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| 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.

On Tue, 17 Jun 2014 21:35:21 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.

You didn't notice the discontinuities?

...Jim Thompson

Sure, but they are down in the "noise" of part-part differences.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation

On Tue, 17 Jun 2014 21:57:08 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 21:35:21 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.

You didn't notice the discontinuities?

...Jim Thompson

Sure, but they are down in the "noise" of part-part differences.

Refer back in the history of this group, and Win Hill's concern about
operation in the subthreshold region. Use as a low noise amplifier is
quite different from just using the device as a switch.

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| 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.

On Wed, 18 Jun 2014 07:40:52 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 21:57:08 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 21:35:21 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.

You didn't notice the discontinuities?

...Jim Thompson

Sure, but they are down in the "noise" of part-part differences.

Refer back in the history of this group, and Win Hill's concern about
operation in the subthreshold region. Use as a low noise amplifier is
quite different from just using the device as a switch.

...Jim Thompson

Here's a graph that I found in our PDATA folder for the 2N7000. I don't know
where it came from, possibly from Win.

https://dl.dropboxusercontent.com/u/...ff_leakage.pdf

(people should sign and date everything that they create)

What does "subthreshold" mean anyhow? It seeme to me that specified gate
thresholds are based on arbitrary drain currents. That curve above has no
threshold.




--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation

On Tue, 17 Jun 2014 18:21:48 -0700, Robert Baer
wrote:

Jim Thompson wrote:
On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson
Attached is an old Infineon lib of FETs, etc that may be of use.

No model level higher then Level=3... that is, early school-boy
text-book complexity.

The problem is that it is quite rare to see discrete MOS devices
modeled properly as BSIM3v3.

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| 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.

On Wed, 18 Jun 2014 07:50:07 -0700, John Larkin
wrote:

On Wed, 18 Jun 2014 07:40:52 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 21:57:08 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 21:35:21 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.

You didn't notice the discontinuities?

...Jim Thompson

Sure, but they are down in the "noise" of part-part differences.

Refer back in the history of this group, and Win Hill's concern about
operation in the subthreshold region. Use as a low noise amplifier is
quite different from just using the device as a switch.

...Jim Thompson

Here's a graph that I found in our PDATA folder for the 2N7000. I don't know
where it came from, possibly from Win.

https://dl.dropboxusercontent.com/u/...ff_leakage.pdf

(people should sign and date everything that they create)

What does "subthreshold" mean anyhow? It seeme to me that specified gate
thresholds are based on arbitrary drain currents. That curve above has no
threshold.

That's not "leakage", it's the natural square-law behavior of MOS
devices below "threshold"... sometimes used to make faux bandgaps with
MOS ;-)

I suspect Joerg regularly works down in this region.

I recently participated in the design of a medical device (chip) where
_everything_ operated subthreshold... the oscillators I mentioned
before... 1kHz at 6nA, 1MHz at 1.2uA

The definition of "threshold" is a vague. I have these papers that I
can share, if any are interested...

....\ModelingIssues\ThresholdModeling_SalcedoEtAl. pdf

....\MOS-GateCharge\WinHill_subthreshold_mosfet_model.pdf (graphs)

....\MOS-GateCharge\Win Hill Data\2n7000_data_graphs.xls (data)

....\SubthresholdEffects\CurrentMirror_Novel_Subth resholdRegion.pdf

....\SubthresholdEffects\ExploitingSubthresholdMOS FET_Behavior.pdf

....\SubthresholdEffects\ReferencesFromSubthreshol d MOSFETs.pdf

....\SubthresholdEffects\SubthresholdDeviceModelin g.pdf

....\SubthresholdEffects\SubthresholdMOSforUltra-LowPower.pdf

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| 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.

On 06/18/2014 10:50 AM, John Larkin wrote:
On Wed, 18 Jun 2014 07:40:52 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 21:57:08 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 21:35:21 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.

You didn't notice the discontinuities?

...Jim Thompson

Sure, but they are down in the "noise" of part-part differences.

Refer back in the history of this group, and Win Hill's concern about
operation in the subthreshold region. Use as a low noise amplifier is
quite different from just using the device as a switch.

...Jim Thompson

Here's a graph that I found in our PDATA folder for the 2N7000. I don't know
where it came from, possibly from Win.

https://dl.dropboxusercontent.com/u/...ff_leakage.pdf

(people should sign and date everything that they create)

What does "subthreshold" mean anyhow? It seeme to me that specified gate
thresholds are based on arbitrary drain currents. That curve above has no
threshold.

Very pretty. What was V_GS?

Cheers

Phil Hobbs


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is
about as good as any other. Real-life parts will be all over the map.

Not if the board function depends on sub-threshold behavior!

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

On Wed, 18 Jun 2014 12:40:26 -0400, Phil Hobbs
wrote:

On 06/18/2014 10:50 AM, John Larkin wrote:
On Wed, 18 Jun 2014 07:40:52 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 21:57:08 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 21:35:21 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.

You didn't notice the discontinuities?

...Jim Thompson

Sure, but they are down in the "noise" of part-part differences.

Refer back in the history of this group, and Win Hill's concern about
operation in the subthreshold region. Use as a low noise amplifier is
quite different from just using the device as a switch.

...Jim Thompson

Here's a graph that I found in our PDATA folder for the 2N7000. I don't know
where it came from, possibly from Win.

https://dl.dropboxusercontent.com/u/...ff_leakage.pdf

(people should sign and date everything that they create)

What does "subthreshold" mean anyhow? It seeme to me that specified gate
thresholds are based on arbitrary drain currents. That curve above has no
threshold.

Very pretty. What was V_GS?

Cheers

Phil Hobbs

Do you mean Vds? I don't know.


--

John Larkin Highland Technology, Inc

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

On 6/18/2014 5:06 PM, John Larkin wrote:
On Wed, 18 Jun 2014 12:40:26 -0400, Phil Hobbs
wrote:

On 06/18/2014 10:50 AM, John Larkin wrote:
On Wed, 18 Jun 2014 07:40:52 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 21:57:08 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 21:35:21 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.

You didn't notice the discontinuities?

...Jim Thompson

Sure, but they are down in the "noise" of part-part differences.

Refer back in the history of this group, and Win Hill's concern about
operation in the subthreshold region. Use as a low noise amplifier is
quite different from just using the device as a switch.

...Jim Thompson

Here's a graph that I found in our PDATA folder for the 2N7000. I don't know
where it came from, possibly from Win.

https://dl.dropboxusercontent.com/u/...ff_leakage.pdf

(people should sign and date everything that they create)

What does "subthreshold" mean anyhow? It seeme to me that specified gate
thresholds are based on arbitrary drain currents. That curve above has no
threshold.

Very pretty. What was V_GS?

Cheers

Phil Hobbs

Do you mean Vds? I don't know.

V_DS, right. Ah, well, I'll have to quit snuggling with my computer and
actually do some measurements.

Cheers

Phil Hobbs


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

On 6/18/2014 5:06 PM, John Larkin wrote:
On Wed, 18 Jun 2014 12:40:26 -0400, Phil Hobbs
wrote:

On 06/18/2014 10:50 AM, John Larkin wrote:
On Wed, 18 Jun 2014 07:40:52 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 21:57:08 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 21:35:21 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 19:44:42 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 14:23:41 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 14:15:32 -0700, Jim Thompson
wrote:

On Tue, 17 Jun 2014 12:02:40 -0700, John Larkin
wrote:

On Tue, 17 Jun 2014 09:38:18 -0700, Jim Thompson
wrote:

Last time I tested several 2N7000 Spice models (2005), there was huge
variance between them, and some down-right non-physical behavior.

Has anyone found a better 2N7000 model since then?

...Jim Thompson

The 2N7000/2N7002 parts themselves vary a lot between manufacturers,
which is why some of our products specify a specific manufacturer for
these parts.

What non-physical behavior are you seeing?

All but the Supertex model failed to model ANY behavior below
threshold, and the Supertex model had discontinuities in the ID/VDS
curve blending... guaranteed to cause simulator convergence issues.

...Jim Thompson

I forgot to reference my old post (4/6/2005)...

http://www.analog-innovations.com/SE...7000Models.pdf

Second page tells it all.

...Jim Thompson

If you're actually designing boards with 2N7000s, any of those curves is about
as good as any other. Real-life parts will be all over the map.

You didn't notice the discontinuities?

...Jim Thompson

Sure, but they are down in the "noise" of part-part differences.

Refer back in the history of this group, and Win Hill's concern about
operation in the subthreshold region. Use as a low noise amplifier is
quite different from just using the device as a switch.

...Jim Thompson

Here's a graph that I found in our PDATA folder for the 2N7000. I don't know
where it came from, possibly from Win.

https://dl.dropboxusercontent.com/u/...ff_leakage.pdf

(people should sign and date everything that they create)

What does "subthreshold" mean anyhow? It seeme to me that specified gate
thresholds are based on arbitrary drain currents. That curve above has no
threshold.

Very pretty. What was V_GS?

Cheers

Phil Hobbs

Do you mean Vds? I don't know.

V_DS, right. Ah, well, I'll have to quit snuggling with my computer and
actually do some measurements.

Cheers

Phil Hobbs


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net