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MOSFET
Sci.Electronics.Design is a worldwide Usenet news group that is used to discuss various aspects of Electronic Circuit Design.
We found 594 threads matching "mosfet"
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The most relevant threads are listed first
Inverting vs NonInverting Mosfet Driver
D from BC - 2010-02-08 16:01:00
I have some fuzzy recollection of reading to the effect that
noninverting mosfet drivers are more prone to instability due to layout
effects.
Confirm?
Just doing a quick sim in my head:
With poor layout, when a noninverting mosfet driver turns on (sourcing),
the signal ground pops up du...
mosfet gate drive impedance
gearhead - 2008-01-14 15:15:00
I have a situation where I need to use a pretty stiff pull-up resistor
on a mosfet gate because I'm going to use a comparator
to turn it off, and I plan to limit the current the comparator sinks
to about 5 mA.
The N-mosfet source will be sitting at 15 volts and the gate drive
comes from a volta...Re: NimH AAA to 5V, suggestions?
Jan Panteltje - 2010-08-06 13:52:00
On a sunny day (Fri, 6 Aug 2010 09:35:10 -0700 (PDT)) it happened
dagmargoodboat@yahoo.com wrote in
:
PS
I just had a cool idea how to do the auto shut off:
-------------> to converter
| +
1.2V NiMH
_____| -
| d
=== g -----------------------...MOSFET Driver cannot drive a MOSFET? or something wrong?
2008-05-13 02:31:00
Here is my circuits, simple, yet, when I disconnect the MOSFET and
load from the circuits, the waveform, duty cycle, amplitude,
everything else is correct. After I connect the mosfet and load (here
I didn't use a laser diode, in stead I use a 1 ohm power resistor),
all 're in a messy! MOSFET is ...Problem applying a mosfet
default - 2008-01-31 09:45:00
I'm trying to use a logic level mosfet to switch on a camera. The
camera is a 3 volt type designed for AAA batteries and works fine with
NiMH down to about two volts and alkaline to about two volts.
The mosfet drops about 20 millivolts when operating the camera, yet
for some reason the supply...Mosfet 7.5% increase in RDSON between 25C and 100C
Hammy - 2010-01-13 21:12:00
Anybody hear of a mosfet that only has a 7.5% increase in RDSON
between 25C and 100C.
Because according to ST the STD15NF10 is just such a mosfet.
I'm guessing this is a typo.
Data sheet pg7 figure 11.
http://www.st.com/stonline/products/literature/ds/7080.pdf
...Re: relays
John Fields - 2008-11-14 11:55:00
On Fri, 14 Nov 2008 10:47:11 -0600, John Fields
wrote:
>
> It's exactly the same as charging up the gate of a MOSFET and yet you
> don't say a MOSFET has infinite gain, do you?
^
power
JF
...High-Side MOSFET gate driver voltage generation
wolti_At - 2008-08-23 06:25:00
Hello,
I am looking for some advice for controlling an N-channel MOSFET
(IPD64CN10N). Right now for testing I was using an IR2112 driver which
I already had available and a small isolation transformer. I do not
like this because this is a) quite expensive and b) a not so elegant
solution. M...PWM with low side MOSFET drive for DC motor (coast or brake when off?)
Brandon - 2008-03-20 17:36:00
I need to correct my understanding of a low side MOSFET switching for
a DC motor. I have a DC motor in parallel with a diode connected to
the drain of an n-channel MOSFET on one side (anode side of the diode)
and the motor supply voltage on the other. When the MOSFET is
switched on, the motor ...Re: high efficient flyback for about 100W
MooseFET - 2008-07-02 09:44:00
On Jul 2, 5:03=A0am, "A.D." wrote:
> Hello.
>
> Has anyone ever built a DC-DC (about Vin 20-50V; Vout 14V) flyback
> converter, with an efficiency of =A0about 90%, worst case?
I assume you are talking of making an isolated flyback since they
always increase the voltage in the non-isol...demultiplexer mosfet driver
Jon Slaughter - 2009-09-24 13:29:00
Do they make a mosfet pack that acts can be used as a demultiplexer? I need
6 mosfet drivers for a total of about 3A max, 6*0.5A, that can be control
like a demultiplexer. I would like to have this run at around 50Mhz.
Unfortunately it needs to be high side mosfets with Vdrain about 3-5V and
...MOSFET failure
Michael - 2009-08-06 09:24:00
I have a MOSFET consistently blowing up. 550V part, 230V in, buck
configuration, transformer drive.
The symptom is always the same: g-s measures short. What may be
causing it? Is it gate drive overvoltage?
Thanks
...Re: Learning Mosfets...RdsON Warm Up?
langwadt@fonz.dk - 2009-12-17 15:53:00
On 17 Dec., 20:17, D from BC wrote:
> I got a 10 ohm carbon switched by a mosfet(TO-220).
> Spec sheet: Rdson=0.17ohms at 9.8amps with R to drain.
> Source to gnd.
> 20V regulated supply
>
> On the scope I've noticed that Vdson is still increasing in voltage
> (Ids still increasi...2Amp CW Current Source, BJT or MOSFET?
2009-03-17 14:40:00
Hi,
I am thinking about a 2Amp CW current source project. I prefer a
simple, working on the linear region current source. Op-Amp +
Transistor.
Does MOSFET have better performance than BJT at this point? Which one
has lower resistance in linear region at 2A?
Do you have recommendations fo...Freewheeling or Generation(Motor)
Jon Slaughter - 2008-08-05 15:13:00
Is it common for a motor that is configured in an H-Bridge to be shorted out
when it is "freewheeling"(so it no longer is freewheeling)? Does this cause
the motor to loose speed slowing it down and waste power?
Basically I'm talking about what I should do with the low side mosfet when
turni...Low noise small signal MOSFET
LeeVit2Dweeber - 2010-04-03 11:04:00
I'm trying to accurately source a ~ 10 microampere current. Accurate
implies no BJTs (hfe isn't accurate and drifts with temperature). I have a
design that should work if the DC gate current to an enhancement mode
n-channel MOSFET is < 1 pA (and, being as greedy as anyone, < 0.1 pA would
make my...Bootstrapping a MOSFET
2008-02-17 00:10:00
Hello all! I've never had to post a question before, usually I'm able
to search around and find something but this time I seem to be stuck.
I'm building a switching power supply (half bridge) and I'm trying to
figure out a way to drive the High side MOSFET. I think I can use a
bootstrap capaci...MOSFET as shunt interface circuit
Jan Panteltje - 2008-02-07 13:31:00
Using a MOSFET as shunt works, but what if it is 'off'?
I came up with this:
in meter circuit . remote MOSFET power switch
.
------------------------------------- .
...High voltage mosfet driving
James Rollins - 2009-05-07 21:02:00
I'm a bit confused about how to drive a mosfet as a switch when
dealing with high V_DS voltages. I have several nch mosfets with 100V+
up to about 1000V for max source to drain voltages.
I want to create a few buck converter circuits and others to test the
quality of the output but I cannot fo...BJT driver for MOSFET?
Jon Slaughter - 2008-04-07 20:49:00
Can one use bjt's to drive mosfets without any problem? I know its easier to
use a mosfet driver but lets just assume I have a lot of bjt's lying around
and need some good use for them. I don't see any probems with this except
more components a and harder to setup. Just curious as I don't beli...Comparing Mosfet Drivers
D from BC - 2009-03-24 19:57:00
In one corner weighing in at an impressive 9Amps peak is the Microchip
TC4421 mosfet driver
http://ww1.microchip.com/downloads/en/DeviceDoc/21420d.pdf
And in the other corner weighing in at a whimpy 2.5Amps peak is
Fairchild'ss FAN3100 mosfet driver
http://www.fairchildsemi.com/ds/FA%2FFAN310...Mosfet small resistor on source
PovTruffe - 2010-08-25 15:59:00
Hi,
What is the purpose of the small value resistor R7 inserted on the mosfet source ?
Schematic: http://dl.free.fr/e2ProNRN5
...n-channel mosfet rise-fall time comparison
Jamie Morken - 2008-09-14 13:47:00
Hi,
This 100V n-channel mosfet:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=IPP04CN10NGIN-ND
has a specified rise time about 3x slower than the fall time,
(78ns rise time and 25ns fall time with 1.6ohm gate resistor)
and this 75V n-channel mosfet:
http://search.digik...Re: MOSFET Usage
ian field - 2010-05-25 12:21:00
"neddie" wrote in message
news:4a1cecae-c789-4601-8dd1-34b0daa6d242@y12g2000vbr.googlegroups.com...
On May 25, 1:32 am, "Ron M." wrote:
> On May 22, 10:42 am, "Joe G \(Home\)" wrote:
>
>
>
> > "Ron M." wrote in message
>
> > news:a67274a4-1270-45cf-8c90-4f139be8ad3c@y...mosfet switching time vs temperature
Jamie Morken - 2010-08-15 01:30:00
Hi,
For an n-channel mosfet how does increasing junction temperature effect
the switching time? I was wondering about paralleling mosfets, if one
fet switches a bit faster than the others and heats up, will its
switching time increase or decrease. I am hoping for increase! :)
cheers,
...low current mosfet
2008-10-01 10:25:00
Hello,
I am trying to find locate a low current n-mosfet in discrete
component form. However, all nmoses that I come across (on digikey and
other sites) can conduct a drain current of 25mA or more (when
vgs> vth). I am looking for one that conducts ~100uA when vgs> Vth.
Does such a compone...Re: 12V-12V converter!
MooseFET - 2010-02-03 09:30:00
On Feb 2, 10:23=A0pm, Myauk wrote:
> Dear All,
>
> Is there any such thing as 12V-12V converter?
>
> I have never heard of it before.
Do you need it to be isolated?
For non isolated, you can use a SEPIC converter or:
P-MOSFET
---- --------+-------)))))------+------...Re: switch circuit
Fred Abse - 2009-12-26 13:46:00
On Sat, 19 Dec 2009 18:08:00 -0800, Smitty Two wrote:
> Mosfet, Mosfet, I remember that word from the textbooks. That was a long
> time ago. Let's see, FET = field effect transistor, and moss grows on
> trees. I like the idea, though. If I used three of them I could even use
> a smaller...Re: Idea for regulate a DC with noise-Help
MooseFET - 2008-12-06 13:30:00
On Dec 6, 8:10=A0am, Service.Laborat...@gmail.com wrote:
> On 6 Dic, 16:57, Eeyore
> wrote:
>
> > Service.Laborat...@gmail.com wrote:
> > > I can dissipate power but a good thing would be dissipate minimum as
> > > possible.
> > > So no pass regulator but a simple swithinf st...Application Note 948 - Linear Power Amplifier Using Complementary HEXFETs
2008-07-09 16:44:00
Fascinating reading:
http://www.irf.com/technical-info/appnotes/an-948.pdf
(found from here: http://sound.westhost.com/articles/hexfet.htm)
I've heard that the 2SK1058 is superior for audio, and is the only
MOSFET spec'ed in Slone's book, but that this MOSFET is currently now
unobtanium.
...Re: PROFET BSP450
Wimpie - 2009-12-01 05:56:00
On 1 dic, 06:40, "ydoubl...@gmail.com" wrote:
> Hi All,
>
> Stumbled across a datasheet of BSP450 (miniProfet) from Siemens
> (Infineon). In that datasheet, the pins are denoted as OUT, GND, IN,
> Vbb .... I am unable to draw reference to the conventions used in
> Mosfet (drain,source...Light dimmer
Yvan - 2010-01-24 04:56:00
I want to make light dimmer for my car to use as daytime running lights
(now required here by law), and I found this:
http://www.electronics-tutorials.com/devices/555-light-dimmer.htm
What do you think about this design?
Each headlight bulb is fused separately, and both are grounded at t...High side driving N-channel Mosfet with PWM
Phil in Melbourne - 2008-05-05 07:24:00
So I would have thought that this would be a simple problem but the more
information I get the more I get confused......
I want to PWM a whole lot of LEDs. The current consumption of the bank of
LEDs is in the order of 15 Amps, at 12V.
For reasons I won't go into, my only option is t...Re: synch. or non-synch voltage reg? what's the difference?
Franco - 2008-04-03 12:19:00
On 3 abr, 11:53, Franco wrote:
> Hi guys, I would like to know the difference between synchronous and
> non-synchronous switching voltage regulators. Can someone help me?
>
> Greetings.
Maybe I got the answer. Apparently, synchronous Buck SMPS's use 2
MOSFETs instead of 1 MOSFET and 1...H-Bridge blew up 10 MOSFET a day
NorthBear - 2009-07-15 04:53:00
I had a very sad day with a silly experimental setup.
circuit is here:
http://www.pbase.com/image/114988176/original
I try to drive a thermoelectric cooler with a H-Bridge driven by a
microcontroller. Output 1KHz bi-directional 8A/10V.
From microcontroller the layout is not good, th...Re: inverting dc-dc converter circuit
MooseFET - 2010-01-29 09:53:00
On Jan 28, 9:27=A0pm, John Larkin
wrote:
> This afternoon we were talking with Phil Hobbs about an
> electro-optical thingie we're doing. The prime power is a +15 volt
> wall wart, and we need -30 internally to power some photodiodes and
> opamps and stuff, 30 mA maybe. Our design curren...Re: how to make an active fuse
Jan Panteltje - 2009-04-16 17:56:00
On a sunny day (Thu, 16 Apr 2009 14:35:28 -0700 (PDT)) it happened Tim
Williams wrote in
:
> On Apr 16, 3:51 pm, panfilero wrote:
> > Hello,
> >
> > Can anyone suggest a way to make an active fuse using very few
> > components? I'd like an electronic fuse that opens after... sa...Double gate Mosfets
2008-11-14 12:40:00
Hi all!
I need to build an ultra low noise cascode amplifier and I want to use
a double gate mosfet to gain better performances with respect to
jfets.
I need a very low gate leakage current, because it worsens the SNR.
I found some interesting components made for RF purposes by NXP, but
al...How to acquire a 30V square wave from a 3V square wave with a frequency of 500 KHz?
Hector.X - 2009-05-04 21:27:00
It has a capacitive load and the output signal will has a rising/
falling edge no more than 40 ns.
The falling edge will be gentle if using a proper n-channel MOSFET
switch. However, the rising edge is really gentle.
A push-pull structure could be one of the solutions, but I find that
the MOS...Re: 8051 On/Off Circuit
MooseFET - 2007-12-29 11:27:00
On Dec 28, 2:25 pm, mpm wrote:
> This is general enough to be of use to several folks.
>
> Anybody got a simple momentary keypad-switchable ON-OFF circuit for a
> 8051 (or similar)?
> Figure about 100 mA MAX, and will be battery operated (9-Volt).
>
> Program will run for a minute o...