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Groups > sci.electronics.design > #452689 > unrolled thread
| Started by | rickman <gnuarm@gmail.com> |
|---|---|
| First post | 2017-03-20 00:34 -0400 |
| Last post | 2017-03-22 20:40 -0800 |
| Articles | 20 on this page of 35 — 13 participants |
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Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-20 00:34 -0400
Re: Low Threshold MOSFET "Lund-Nielsen, Jorgen" <jorgen.lund-nielsen@xyz123desy.de> - 2017-03-20 13:30 +0100
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-20 15:26 -0400
Re: Low Threshold MOSFET Hul Tytus <ht@panix.com> - 2017-03-20 22:47 +0000
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-20 21:42 -0400
Re: Low Threshold MOSFET Joerg <news@analogconsultants.com> - 2017-03-21 08:03 -0700
Re: Low Threshold MOSFET Hul Tytus <ht@panix.com> - 2017-03-21 23:36 +0000
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-21 20:06 -0400
Re: Low Threshold MOSFET Allan Herriman <allanherriman@hotmail.com> - 2017-03-20 12:56 +0000
Re: Low Threshold MOSFET Winfield Hill <hill@rowland.harvard.edu> - 2017-03-20 06:34 -0700
Re: Low Threshold MOSFET Clive Arthur <cliveta@nowaytoday.co.uk> - 2017-03-20 13:08 +0000
Re: Low Threshold MOSFET Tim Wescott <tim@seemywebsite.com> - 2017-03-20 11:03 -0500
Re: Low Threshold MOSFET Joerg <news@analogconsultants.com> - 2017-03-20 15:59 -0700
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-20 22:29 -0400
Re: Low Threshold MOSFET Joerg <news@analogconsultants.com> - 2017-03-21 08:00 -0700
Re: Low Threshold MOSFET "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-03-21 01:02 -0500
Re: Low Threshold MOSFET kevin93 <kevin@whitedigs.com> - 2017-03-22 07:15 -0700
Re: Low Threshold MOSFET John S <Sophi.2@invalid.org> - 2017-03-22 09:36 -0500
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-22 14:03 -0400
Re: Low Threshold MOSFET John S <Sophi.2@invalid.org> - 2017-03-22 13:43 -0500
Re: Low Threshold MOSFET Winfield Hill <hill@rowland.harvard.edu> - 2017-03-22 12:01 -0700
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-22 15:14 -0400
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-22 15:18 -0400
Re: Low Threshold MOSFET Joerg <news@analogconsultants.com> - 2017-03-23 10:29 -0700
Re: Low Threshold MOSFET John S <Sophi.2@invalid.org> - 2017-03-22 15:07 -0500
Re: Low Threshold MOSFET tabbypurr@gmail.com - 2017-03-23 20:45 -0700
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-24 00:43 -0400
Re: Low Threshold MOSFET Robert Baer <robertbaer@localnet.com> - 2017-03-23 22:24 -0800
Re: Low Threshold MOSFET tabbypurr@gmail.com - 2017-03-24 03:59 -0700
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-24 12:50 -0400
Re: Low Threshold MOSFET tabbypurr@gmail.com - 2017-03-25 00:51 -0700
Re: Low Threshold MOSFET Joerg <news@analogconsultants.com> - 2017-03-25 09:47 -0700
Re: Low Threshold MOSFET rickman <gnuarm@gmail.com> - 2017-03-25 13:54 -0400
Re: Low Threshold MOSFET Joerg <news@analogconsultants.com> - 2017-03-24 09:37 -0700
Re: Low Threshold MOSFET Robert Baer <robertbaer@localnet.com> - 2017-03-22 20:40 -0800
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-03-20 00:34 -0400 |
| Subject | Low Threshold MOSFET |
| Message-ID | <oanlv1$af7$1@dont-email.me> |
I was looking to order some low current MOSFETs and realized all the popular items had thresholds of 3 volts and higher. I would like to use something that turns on pretty well at 3 volts so it won't need a 5 volt PSU. Any suggestions? I'm looking for a TO-92 case preferably but surface mount will be ok too. I could have sworn some years ago I tracked down a number of low threshold voltage FETs. But maybe those devices operated under 5 volts rather than under 3.3 volts. -- Rick C
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| From | "Lund-Nielsen, Jorgen" <jorgen.lund-nielsen@xyz123desy.de> |
|---|---|
| Date | 2017-03-20 13:30 +0100 |
| Message-ID | <eja0boFi5kdU1@mid.individual.net> |
| In reply to | #452689 |
Am 20.03.2017 um 05:34 schrieb rickman: > I was looking to order some low current MOSFETs and realized all the > popular items had thresholds of 3 volts and higher. I would like to use > something that turns on pretty well at 3 volts so it won't need a 5 volt > PSU. Any suggestions? I'm looking for a TO-92 case preferably but > surface mount will be ok too. > > I could have sworn some years ago I tracked down a number of low > threshold voltage FETs. But maybe those devices operated under 5 volts > rather than under 3.3 volts. > The 2N7000 (200 mAmps, 60 Volts) has Gate Threshold Voltage of 0.8V min to 3.0V max <https://www.onsemi.com/pub/Collateral/2N7000-D.PDF> Jorgen
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-03-20 15:26 -0400 |
| Message-ID | <oapa8h$nq0$1@dont-email.me> |
| In reply to | #452707 |
On 3/20/2017 8:30 AM, Lund-Nielsen, Jorgen wrote: > Am 20.03.2017 um 05:34 schrieb rickman: >> I was looking to order some low current MOSFETs and realized all the >> popular items had thresholds of 3 volts and higher. I would like to use >> something that turns on pretty well at 3 volts so it won't need a 5 volt >> PSU. Any suggestions? I'm looking for a TO-92 case preferably but >> surface mount will be ok too. >> >> I could have sworn some years ago I tracked down a number of low >> threshold voltage FETs. But maybe those devices operated under 5 volts >> rather than under 3.3 volts. >> > > The 2N7000 (200 mAmps, 60 Volts) > > has Gate Threshold Voltage of 0.8V min to 3.0V max > > <https://www.onsemi.com/pub/Collateral/2N7000-D.PDF> That's the threshold voltage where drain current begins essentially. Looking at the drain current vs. drain-gate voltage typical curves the current at 3.0 volts is well under 100 mA. I suppose I could put two or three in parallel. I didn't want to use an NPN because the base current goes through the emitter resistor which I'm using to measure the current, but when I did a simulation that current is pretty small, so I suppose it's not really a problem. The resistors are only 1% accurate. I've got NPNs on hand, so I'll use one for now. -- Rick C
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| From | Hul Tytus <ht@panix.com> |
|---|---|
| Date | 2017-03-20 22:47 +0000 |
| Message-ID | <oapm6n$j4c$1@reader1.panix.com> |
| In reply to | #452766 |
Fairchild (whoever now) has a nice n channel device speced, if I remember correctly, at 1 volt max turn on. It served as a voltage follower op amp with lots of offset. They came from Mouser. Hul rickman <gnuarm@gmail.com> wrote: > On 3/20/2017 8:30 AM, Lund-Nielsen, Jorgen wrote: > > Am 20.03.2017 um 05:34 schrieb rickman: > >> I was looking to order some low current MOSFETs and realized all the > >> popular items had thresholds of 3 volts and higher. I would like to use > >> something that turns on pretty well at 3 volts so it won't need a 5 volt > >> PSU. Any suggestions? I'm looking for a TO-92 case preferably but > >> surface mount will be ok too. > >> > >> I could have sworn some years ago I tracked down a number of low > >> threshold voltage FETs. But maybe those devices operated under 5 volts > >> rather than under 3.3 volts. > >> > > > > The 2N7000 (200 mAmps, 60 Volts) > > > > has Gate Threshold Voltage of 0.8V min to 3.0V max > > > > <https://www.onsemi.com/pub/Collateral/2N7000-D.PDF> > That's the threshold voltage where drain current begins essentially. > Looking at the drain current vs. drain-gate voltage typical curves the > current at 3.0 volts is well under 100 mA. > I suppose I could put two or three in parallel. > I didn't want to use an NPN because the base current goes through the > emitter resistor which I'm using to measure the current, but when I did > a simulation that current is pretty small, so I suppose it's not really > a problem. The resistors are only 1% accurate. > I've got NPNs on hand, so I'll use one for now. > -- > Rick C
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-03-20 21:42 -0400 |
| Message-ID | <oaq07v$1mh$1@dont-email.me> |
| In reply to | #452794 |
On 3/20/2017 6:47 PM, Hul Tytus wrote: > Fairchild (whoever now) has a nice n channel device speced, if I remember > correctly, at 1 volt max turn on. It served as a voltage follower op amp > with lots of offset. They came from Mouser. Any more info than that? Threshold voltage is not easy to search on because everyone specs it at a different current. Also the threshold voltage can be a *lot* lower than the fully on voltage which is the important one. Or is that what you mean? Still, it takes a lot of data sheet searching to find a part that is optimal for low voltage control and that is why I asked here. I am hoping to benefit from other's experience. -- Rick C
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| From | Joerg <news@analogconsultants.com> |
|---|---|
| Date | 2017-03-21 08:03 -0700 |
| Message-ID | <ejctkuF5friU2@mid.individual.net> |
| In reply to | #452834 |
On 2017-03-20 18:42, rickman wrote: > On 3/20/2017 6:47 PM, Hul Tytus wrote: >> Fairchild (whoever now) has a nice n channel device speced, if I remember >> correctly, at 1 volt max turn on. It served as a voltage follower op amp >> with lots of offset. They came from Mouser. > > Any more info than that? Threshold voltage is not easy to search on > because everyone specs it at a different current. Also the threshold > voltage can be a *lot* lower than the fully on voltage which is the > important one. Or is that what you mean? Still, it takes a lot of data > sheet searching to find a part that is optimal for low voltage control > and that is why I asked here. I am hoping to benefit from other's > experience. > Don't go by any graphs. Those only represent typical values. The processes used for MOSFETs have huge tolerances in threshold voltage, easily +/-30%. The only values to go by are guaranteed max Rdson values for a stated gate drive voltage. Typically two to five different gate drive voltages are spec'd. Must be in the tables. -- Regards, Joerg http://www.analogconsultants.com/
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| From | Hul Tytus <ht@panix.com> |
|---|---|
| Date | 2017-03-21 23:36 +0000 |
| Message-ID | <oasddb$4s0$1@reader1.panix.com> |
| In reply to | #452834 |
Try fdv301n. I'll verify that in the morning if I get to the office. Hul rickman <gnuarm@gmail.com> wrote: > On 3/20/2017 6:47 PM, Hul Tytus wrote: > > Fairchild (whoever now) has a nice n channel device speced, if I remember > > correctly, at 1 volt max turn on. It served as a voltage follower op amp > > with lots of offset. They came from Mouser. > Any more info than that? Threshold voltage is not easy to search on > because everyone specs it at a different current. Also the threshold > voltage can be a *lot* lower than the fully on voltage which is the > important one. Or is that what you mean? Still, it takes a lot of data > sheet searching to find a part that is optimal for low voltage control > and that is why I asked here. I am hoping to benefit from other's > experience. > -- > Rick C
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-03-21 20:06 -0400 |
| Message-ID | <oasf10$naq$1@dont-email.me> |
| In reply to | #452966 |
On 3/21/2017 7:36 PM, Hul Tytus wrote: > Try fdv301n. I'll verify that in the morning if I get to the office. Good number. Thanks. -- Rick C
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| From | Allan Herriman <allanherriman@hotmail.com> |
|---|---|
| Date | 2017-03-20 12:56 +0000 |
| Message-ID | <58cfd178$0$11093$c3e8da3@news.astraweb.com> |
| In reply to | #452689 |
On Mon, 20 Mar 2017 00:34:21 -0400, rickman wrote: > I was looking to order some low current MOSFETs and realized all the > popular items had thresholds of 3 volts and higher. I would like to use > something that turns on pretty well at 3 volts so it won't need a 5 volt > PSU. Any suggestions? I'm looking for a TO-92 case preferably but > surface mount will be ok too. > > I could have sworn some years ago I tracked down a number of low > threshold voltage FETs. But maybe those devices operated under 5 volts > rather than under 3.3 volts. I assume you want N channel and that "low current" means up to a few hundred mA. I use a lot of BSS138 (VGS(th) 0.5 to 1.5V) when driving from 3.3V logic, and DMG1012T (VGS(th) 0.5 to 1.0V) when driving from 1.8V logic. Both are cheap and readily available. Regards, Allan
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| From | Winfield Hill <hill@rowland.harvard.edu> |
|---|---|
| Date | 2017-03-20 06:34 -0700 |
| Message-ID | <oaolog015a@drn.newsguy.com> |
| In reply to | #452708 |
Allan Herriman wrote...
>
> ... DMG1012T (VGS(th) 0.5 to 1.0V) when driving from 1.8V logic.
The DMG1012UW is in a bit larger package, 1.3mm vs 1mm
lead spacing. The DMG1013UW is a p-channel equivalent.
--
Thanks,
- Win
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| From | Clive Arthur <cliveta@nowaytoday.co.uk> |
|---|---|
| Date | 2017-03-20 13:08 +0000 |
| Message-ID | <oaok3c$17b$1@dont-email.me> |
| In reply to | #452689 |
On 20/03/2017 04:34, rickman wrote: > I was looking to order some low current MOSFETs and realized all the > popular items had thresholds of 3 volts and higher. I would like to use > something that turns on pretty well at 3 volts so it won't need a 5 volt > PSU. Any suggestions? I'm looking for a TO-92 case preferably but > surface mount will be ok too. > > I could have sworn some years ago I tracked down a number of low > threshold voltage FETs. But maybe those devices operated under 5 volts > rather than under 3.3 volts. 'logic level mosfet' is a good search term. Cheers -- Clive
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| From | Tim Wescott <tim@seemywebsite.com> |
|---|---|
| Date | 2017-03-20 11:03 -0500 |
| Message-ID | <KdadnZNl4rXxYFLFnZ2dnUU7-RmdnZ2d@giganews.com> |
| In reply to | #452689 |
On Mon, 20 Mar 2017 00:34:21 -0400, rickman wrote: > I was looking to order some low current MOSFETs and realized all the > popular items had thresholds of 3 volts and higher. I would like to use > something that turns on pretty well at 3 volts so it won't need a 5 volt > PSU. Any suggestions? I'm looking for a TO-92 case preferably but > surface mount will be ok too. > > I could have sworn some years ago I tracked down a number of low > threshold voltage FETs. But maybe those devices operated under 5 volts > rather than under 3.3 volts. Go DigiKey searching on FETs. Choose "logic level" as a category. If I remember, you can also choose the gate drive voltage -- choose 3.3V. You should get some candidates to ponder over. Alternately, maybe a bipolar makes sense? Zetex invented some pretty awesome little bipolar transistors before they got bought out by Diodes, Inc. -- Tim Wescott Control systems, embedded software and circuit design I'm looking for work! See my website if you're interested http://www.wescottdesign.com
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| From | Joerg <news@analogconsultants.com> |
|---|---|
| Date | 2017-03-20 15:59 -0700 |
| Message-ID | <ejb55uFpkn0U1@mid.individual.net> |
| In reply to | #452689 |
On 2017-03-19 21:34, rickman wrote: > I was looking to order some low current MOSFETs and realized all the > popular items had thresholds of 3 volts and higher. I would like to use > something that turns on pretty well at 3 volts so it won't need a 5 volt > PSU. Any suggestions? I'm looking for a TO-92 case preferably but > surface mount will be ok too. > > I could have sworn some years ago I tracked down a number of low > threshold voltage FETs. But maybe those devices operated under 5 volts > rather than under 3.3 volts. > Assuming you want to switch power to some circuit and thus need P-channel: http://www.diodes.com/assets/Datasheets/DMP2100U.pdf Key is that Rdson is guaranteed at your min drive voltage, not just in the graphs but in the tables. N-channel example: http://www.diodes.com/assets/Datasheets/DMP2100U.pdf A beefier one: http://www.diodes.com/assets/Datasheets/ds31837.pdf -- Regards, Joerg http://www.analogconsultants.com/
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-03-20 22:29 -0400 |
| Message-ID | <oaq30g$85v$1@dont-email.me> |
| In reply to | #452798 |
On 3/20/2017 6:59 PM, Joerg wrote: > On 2017-03-19 21:34, rickman wrote: >> I was looking to order some low current MOSFETs and realized all the >> popular items had thresholds of 3 volts and higher. I would like to use >> something that turns on pretty well at 3 volts so it won't need a 5 volt >> PSU. Any suggestions? I'm looking for a TO-92 case preferably but >> surface mount will be ok too. >> >> I could have sworn some years ago I tracked down a number of low >> threshold voltage FETs. But maybe those devices operated under 5 volts >> rather than under 3.3 volts. >> > > Assuming you want to switch power to some circuit and thus need P-channel: > > http://www.diodes.com/assets/Datasheets/DMP2100U.pdf > > Key is that Rdson is guaranteed at your min drive voltage, not just in > the graphs but in the tables. > > N-channel example: > > http://www.diodes.com/assets/Datasheets/DMP2100U.pdf > > A beefier one: > > http://www.diodes.com/assets/Datasheets/ds31837.pdf The DMP2100U is a P channel and I am looking for an N channel device. However, the DMN2075U is N channel and looks like a very good device for very low voltage controls. Actually, I might need the P channel device for something else later. Thanks. -- Rick C
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| From | Joerg <news@analogconsultants.com> |
|---|---|
| Date | 2017-03-21 08:00 -0700 |
| Message-ID | <ejctg3F5friU1@mid.individual.net> |
| In reply to | #452838 |
On 2017-03-20 19:29, rickman wrote: > On 3/20/2017 6:59 PM, Joerg wrote: >> On 2017-03-19 21:34, rickman wrote: >>> I was looking to order some low current MOSFETs and realized all the >>> popular items had thresholds of 3 volts and higher. I would like to use >>> something that turns on pretty well at 3 volts so it won't need a 5 volt >>> PSU. Any suggestions? I'm looking for a TO-92 case preferably but >>> surface mount will be ok too. >>> >>> I could have sworn some years ago I tracked down a number of low >>> threshold voltage FETs. But maybe those devices operated under 5 volts >>> rather than under 3.3 volts. >>> >> >> Assuming you want to switch power to some circuit and thus need >> P-channel: >> >> http://www.diodes.com/assets/Datasheets/DMP2100U.pdf >> >> Key is that Rdson is guaranteed at your min drive voltage, not just in >> the graphs but in the tables. >> >> N-channel example: >> >> http://www.diodes.com/assets/Datasheets/DMP2100U.pdf >> >> A beefier one: >> >> http://www.diodes.com/assets/Datasheets/ds31837.pdf > > The DMP2100U is a P channel and I am looking for an N channel device. > However, the DMN2075U is N channel and looks like a very good device for > very low voltage controls. Actually, I might need the P channel device > for something else later. Thanks. > You are welcome. They also make duals in small SMT 6-pin packages if you are ever fighting real estate on a board. When it has to be rock-bottom in cost a BJT can be the better choice and those also come "pre-biased" where there is a series bases resistor inside its package and sometimes also a B-E resistor. Some folks call them "digital transistors". -- Regards, Joerg http://www.analogconsultants.com/
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| From | "Tim Williams" <tiwill@seventransistorlabs.com> |
|---|---|
| Date | 2017-03-21 01:02 -0500 |
| Message-ID | <oaqfgg$s23$1@dont-email.me> |
| In reply to | #452689 |
Shop for parts with Vds < 30V. That's the biggest determining factor in transconductance per area. I namedropped RUM001L02T2CL here the other day. It's also very tiny, good for saving PCB area. Tim -- Seven Transistor Labs, LLC Electrical Engineering Consultation and Contract Design Website: http://seventransistorlabs.com "rickman" <gnuarm@gmail.com> wrote in message news:oanlv1$af7$1@dont-email.me... >I was looking to order some low current MOSFETs and realized all the >popular items had thresholds of 3 volts and higher. I would like to use >something that turns on pretty well at 3 volts so it won't need a 5 volt >PSU. Any suggestions? I'm looking for a TO-92 case preferably but surface >mount will be ok too. > > I could have sworn some years ago I tracked down a number of low threshold > voltage FETs. But maybe those devices operated under 5 volts rather than > under 3.3 volts. > > -- > > Rick C
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| From | kevin93 <kevin@whitedigs.com> |
|---|---|
| Date | 2017-03-22 07:15 -0700 |
| Message-ID | <eca7b4c4-959b-49bf-aa18-51b4426950bb@googlegroups.com> |
| In reply to | #452689 |
On Sunday, March 19, 2017 at 9:34:31 PM UTC-7, rickman wrote: > I was looking to order some low current MOSFETs and realized all the > popular items had thresholds of 3 volts and higher. I would like to use > something that turns on pretty well at 3 volts so it won't need a 5 volt > PSU. Any suggestions? I'm looking for a TO-92 case preferably but > surface mount will be ok too. > > I could have sworn some years ago I tracked down a number of low > threshold voltage FETs. But maybe those devices operated under 5 volts > rather than under 3.3 volts. > > -- > > Rick C If you want really low threshold devices Advanced Linear has some zero offset +/-1mV ones. http://www.aldinc.com/pdf/ALD110800.pdf kevin
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| From | John S <Sophi.2@invalid.org> |
|---|---|
| Date | 2017-03-22 09:36 -0500 |
| Message-ID | <oau1v0$fmf$1@dont-email.me> |
| In reply to | #452689 |
On 3/19/2017 11:34 PM, rickman wrote: > I was looking to order some low current MOSFETs and realized all the > popular items had thresholds of 3 volts and higher. I would like to use > something that turns on pretty well at 3 volts so it won't need a 5 volt > PSU. Any suggestions? I'm looking for a TO-92 case preferably but > surface mount will be ok too. > > I could have sworn some years ago I tracked down a number of low > threshold voltage FETs. But maybe those devices operated under 5 volts > rather than under 3.3 volts. > We have been very happy with the FDN337N.
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-03-22 14:03 -0400 |
| Message-ID | <oaue4s$dnc$1@dont-email.me> |
| In reply to | #453033 |
On 3/22/2017 10:36 AM, John S wrote: > On 3/19/2017 11:34 PM, rickman wrote: >> I was looking to order some low current MOSFETs and realized all the >> popular items had thresholds of 3 volts and higher. I would like to use >> something that turns on pretty well at 3 volts so it won't need a 5 volt >> PSU. Any suggestions? I'm looking for a TO-92 case preferably but >> surface mount will be ok too. >> >> I could have sworn some years ago I tracked down a number of low >> threshold voltage FETs. But maybe those devices operated under 5 volts >> rather than under 3.3 volts. >> > > We have been very happy with the FDN337N. I was checking this out and found the prices are >$0.20 even on ebay buying 50 or more. Then I checked aliexpress and found this one... https://www.aliexpress.com/item/Free-shipping-100pcs-lot-FDN337N-screen-337-SOT-23-new-original/32718408974.html?spm=2114.01010208.3.18.ju58Ca&ws_ab_test=searchweb0_0,searchweb201602_2_10065_10130_10068_433_434_10136_10137_10138_10060_10062_10141_10056_10055_10054_301_10059_201_10531_10099_10530_129_10103_10102_10096_10052_10053_10050_10107_10142_10051_10106_10143_10526_10529_10084_10083_10080_10082_10081_10110_10111_10112_10113_10114_10037_10078_10079_10077_10073_10070_10122_10123_10124,searchweb201603_13,afswitch_1,ppcSwitch_5,single_sort_0_default&btsid=bc963ea4-0cae-4be3-95ba-e5fa2d2485cc&algo_expid=5043bdd6-47a3-424c-a756-09e1cbb36cd7-2&algo_pvid=5043bdd6-47a3-424c-a756-09e1cbb36cd7 $2.80 for 100 with free shipping! I would say that have to be fakes, but this store has been online for 3 years with 100%. How can they do that? -- Rick C
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| From | John S <Sophi.2@invalid.org> |
|---|---|
| Date | 2017-03-22 13:43 -0500 |
| Message-ID | <oauged$fmf$2@dont-email.me> |
| In reply to | #453079 |
On 3/22/2017 1:03 PM, rickman wrote: > On 3/22/2017 10:36 AM, John S wrote: >> On 3/19/2017 11:34 PM, rickman wrote: >>> I was looking to order some low current MOSFETs and realized all the >>> popular items had thresholds of 3 volts and higher. I would like to use >>> something that turns on pretty well at 3 volts so it won't need a 5 volt >>> PSU. Any suggestions? I'm looking for a TO-92 case preferably but >>> surface mount will be ok too. >>> >>> I could have sworn some years ago I tracked down a number of low >>> threshold voltage FETs. But maybe those devices operated under 5 volts >>> rather than under 3.3 volts. >>> >> >> We have been very happy with the FDN337N. > > I was checking this out and found the prices are >$0.20 even on ebay > buying 50 or more. Then I checked aliexpress and found this one... > > https://www.aliexpress.com/item/Free-shipping-100pcs-lot-FDN337N-screen-337-SOT-23-new-original/32718408974.html?spm=2114.01010208.3.18.ju58Ca&ws_ab_test=searchweb0_0,searchweb201602_2_10065_10130_10068_433_434_10136_10137_10138_10060_10062_10141_10056_10055_10054_301_10059_201_10531_10099_10530_129_10103_10102_10096_10052_10053_10050_10107_10142_10051_10106_10143_10526_10529_10084_10083_10080_10082_10081_10110_10111_10112_10113_10114_10037_10078_10079_10077_10073_10070_10122_10123_10124,searchweb201603_13,afswitch_1,ppcSwitch_5,single_sort_0_default&btsid=bc963ea4-0cae-4be3-95ba-e5fa2d2485cc&algo_expid=5043bdd6-47a3-424c-a756-09e1cbb36cd7-2&algo_pvid=5043bdd6-47a3-424c-a756-09e1cbb36cd7 > > > $2.80 for 100 with free shipping! I would say that have to be fakes, > but this store has been online for 3 years with 100%. How can they do > that? Don't know. I just discovered that the FDN337N is unobtanium for the next couple of months or more. That prompted me to find a substitute which I have not yet singled out. We need something in the next week or two. Crap! Sorry about that.
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