1000 Threads found on edaboard.com: Hard Switching
A few approaches are viable, such as using a resonant topology (LLC or phase shift bridge converter) or using better FET technology which mitigates the dissipation from hard switching (like GaN FETs).
Power Electronics :: 02-21-2013 17:20 :: mtwieg :: Replies: 14 :: Views: 505
hi! what is the rate of the switching losses in the all mosfet losses...
i am asking this for the mosfets which working hard switching condition....
for example 60khz forward converter mosfet (dc bus voltage 310V) , hard switching and we are driving the gate in optimum speed....(to understand how much ZVS (...)
Electronic Elementary Questions :: 11-27-2004 03:24 :: olemp :: Replies: 3 :: Views: 3548
How can we eliminate dips or peaks which occur at rising or falling edges of the switching pulses?
Professional Hardware and Electronics Design :: 05-24-2005 13:45 :: seyyah :: Replies: 13 :: Views: 1798
Can anyone help me to get the theory of MOSFET Charachteristics & operating principle on the net.
one more doubt what is hard & soft switching in the Mosfet. This i think is used for SMPS. please provide some solution(s) with details.
Thanks in Advance
Electronic Elementary Questions :: 07-24-2006 07:39 :: dtparekh :: Replies: 2 :: Views: 4678
All MOSFET datasheet dynamic specs are related to hard-switching, so what's the dynamic behaviour of MOSFET transistors (tdon, trise, tdoff, tfall, etc) when working a ZCS/ZVS under soft-switching conditions ?
Power Electronics :: 03-01-2011 14:38 :: Regnum :: Replies: 0 :: Views: 727
MOSFET switching - Turn-ON, hard switching
SpringerLink - Technical Physics, Volume 51, Number 5
Power Electronics :: 08-30-2011 02:15 :: raksha singh :: Replies: 1 :: Views: 1141
Resonant switching high voltage IGBT circuits are usually working below 10 kHz based on switching loss considerations, hard switching circuits in a low kHz range, just to shine a light on state-of-the-art. You didn't however tell about your switching frequency constraints, so it's hard to (...)
Power Electronics :: 08-21-2012 10:57 :: FvM :: Replies: 19 :: Views: 788
Input voltage importand for selected topology.
Pushpull is best If you want to use low input voltage.
hard switching technics produce more electromagnetic radiations
therefore you must use soft switching type design at the audio and video circuits.
If you not limited by input voltage any soft switching methode usuable.
Analog Circuit Design :: 05-23-2004 04:48 :: bunalmis :: Replies: 9 :: Views: 2578
Hello, i'm designing a frequency converter and have some questions on it's H-bridge part. It's going to be 1-phase 230V converter, PWMed sine wave with output frequency between 0 to say 500Hz, modulation frequency about 100kHz. The high-rail potential turns out to be 325V. The power rating is not yet determined.
Now, i'm planning to make the hig
Power Electronics :: 06-11-2009 11:02 :: JStuffer :: Replies: 2 :: Views: 3087
Do you think this could be the problem?
What kind of snubber circuit do you recomend to minimize the over voltages?
It's at least a sufficient explanation for catastrophic failure, as observed. There may be other problems, too. I fear, that the bus wiring involves too much leak inductance.
You're talking about snubber capacitor
Power Electronics :: 06-23-2009 01:47 :: FvM :: Replies: 22 :: Views: 8401
I think the spikes are a natural result of the hard switching from the switch causing a sudden flow of excess charge into and out of the capacitors. One possible solution could be to increase the size of the caps, or to ramp the switching process by putting a filter at the switch.
Analog Circuit Design :: 08-19-2010 05:43 :: ammarzouk :: Replies: 2 :: Views: 531
if we take an LLC series resonant Half-bridge.....
-then make the resonant capacitor very large
-then make the leakage term 30 times less than the magnetising term
...then is this still a resoant smps?
How small does the leakage term have to become before we say its no longer a resonant smps?
And is a resonant converter that switche
Power Electronics :: 09-10-2011 17:53 :: grizedale :: Replies: 1 :: Views: 690
For ZCS application you can easily go up to 100khz.(for acceptable efficiency)
For hard switching like motor control 20khz is upper limit for higher efficiencies.
For ZVS 30khz will be fine but due the long tail current of this type ZVS is not efficient as ZCS.
It is a medium speed IGBT and not HIGH SPEED.
Power Electronics :: 12-04-2011 01:03 :: Mehrshad74 :: Replies: 3 :: Views: 598
I mean, that the question can't be exactly answered without knowing the circuit and excitation waveform.
As far as I understand, there's a steady-state sine wave superimposed with a pulse transient. Assumed this is a linear circuit without a DC offset signal, then the trivial explanation is that you are too hasty and didn't wait for the initial
Electronic Elementary Questions :: 02-16-2012 04:42 :: FvM :: Replies: 7 :: Views: 286
A state-of-the-art 13.56 MHz RF power stage would use class E/F respectively hard switching output stages rather than class B for effective operation.
In the said power range, fast MOSFET as used in recent MHz SMPS designs can work. Output filters are needed to "reflect" the harmonics power back to the switcher.
By the way, does your project
Electromagnetic Design and Simulation :: 04-04-2012 18:09 :: FvM :: Replies: 2 :: Views: 476
Assuming you are discussing a buck converter were the freewheel diode is shorted by another mosfet (as in a synchronized rectifier). In fact this is a half bridge topology with an LC low pass filter to get the DC component.
When in discontinuous mode, there will be short bursts of current through mosfets and inductor, no current will flow back to
Electronic Elementary Questions :: 04-12-2012 08:35 :: WimRFP :: Replies: 3 :: Views: 2027
HAS ANYONE USED LM380, LM383, LM384, LM390, LM2002 ETC TO MAKE A RAIL SPLITTER ?
Typical VCC can go as high as 20 to 22 vdc for some of the chips.
No signal, no gain, just inputs pulled low and or tied together.
I would like to drive an Nfet or IGBT +15 or less and -15 or ''more'' (positive) for hard switching.
Rigging up an ISOLATED high s
Analog Circuit Design :: 04-20-2012 04:11 :: hughmanoid :: Replies: 1 :: Views: 761
I think the reason is that a series resonant topology can only transfer AC energy, so you need rectification (as you mentioned also). A buck transfers a DC component, so they are different from eachother. To be honest, I also saw most series resonanit circuits operating as inverters (so not as DC/DC converters). One of the first I saw (
Power Electronics :: 08-01-2012 15:39 :: WimRFP :: Replies: 2 :: Views: 512
I've been looking for a very low noise (less than a mV p-p) medium voltage (~100 V) variable DC supply circuit for a photodiode power supply I'm building. I found the attached circuit in an application note from Linear Technology (AN-118). It is a resonant royer converter and the author claims 100 uV of noise at a 250 V DC output. The low noise is
Power Electronics :: 01-29-2013 12:39 :: narwhaler :: Replies: 7 :: Views: 1120
....the above article states that introducing an inductance into the loop containing the sepic coils and capacitor increases the efficiency. -Can this br true? -have you ever heard of making a hard switching converter more efficiency by simply shoving in an inductor? (the article says its the
Electronic Elementary Questions :: 02-04-2013 02:11 :: treez :: Replies: 0 :: Views: 447
Without knowing details, we should assume that the SMPS is using the expensive silicon carbide schottky device on purpose. If so, a regular ultrafast silicon rectifier can't replace it considering it's much higher switching losses. If the diode is hard switching against a transistor switch, the transistor might be considerably overloaded.
Power Electronics :: 02-09-2013 11:15 :: FvM :: Replies: 1 :: Views: 866
I bought FGA15N120 igbt (six peices) for making a voltage source three phase inverter. I found that its suited for soft switching.Whereas my design is for hard switching. Will this be a problem? Please help...
Hi vinu gopalakrishnan
Not it wouldn't be any special problem . by the way i've saw it's datasheet from fairchild semicon
Power Electronics :: 02-23-2013 23:32 :: goldsmith :: Replies: 2 :: Views: 341
400kHz may well be too fast for the 2113, the gate drive may not be up to it at these frequencies, you would need a discrete buffer between the 2113 and the fets, and a very well designed high speed, low impedance turn off gate drive (12V to 0v in <40nS) at this freq of operation.
Also unless you have an inductive load allowing zero volt turn on o
Power Electronics :: 03-16-2013 16:25 :: Anna Conda :: Replies: 3 :: Views: 404
Hello is that 1milli-Hz or 1 MegaHertz..?
You would possibly be the first in the world to get a 3kW converter going with a switch frequency of 1000,000 Hz, 500nS per half cycle, 20nS transition times? at 400V = 20,000V per uS slew rate, it should be quite a radiator...! of RFI,
Will you be hard switching or resonant topology?
Power Electronics :: 03-22-2013 01:31 :: Anna Conda :: Replies: 4 :: Views: 371
i am working on soft switching converter. i simulated the hard switching boost converter and soft switching boost converter in psim.
while measuring the efficiency ((vout*iout)/(vin*iin)) , the efficiency of hard switching converter is more than the soft switching (...)
Analog Circuit Design :: 03-23-2013 09:58 :: raghavha :: Replies: 4 :: Views: 350
My experience is that a LDMOS device standing off 20V,
has better on-resistance than a standard FET stack of
equivalent capability. This is, perhaps, because the
LDMOS drift region is modulated to higher conductivity
If your LV devices don't have a well that is independent
and can be biased to (say) 17V from substrate, you
Analog Circuit Design :: 05-10-2013 21:01 :: dick_freebird :: Replies: 1 :: Views: 375
MOSFETs are generally not designed with much thought invested into making their body diodes good. Therefore, the body diode will probably exhibit greater on-resistance and perhaps more Qrr (for a given voltage standoff, current rating, Vf, etc). So if the body diode is called on to conduct the entire flyback current rather than a specificall
Electronic Elementary Questions :: 05-22-2013 04:43 :: FvM :: Replies: 4 :: Views: 2027
That's quite a good design although I'm not sure hard switching the channels like that would give best channel separation. The LF VCO to do the tuning should give good frequency stability. Almost all FM receivers there is AFC to 'pull' the receiver to the transmitter frequency so absolute tuing accuracy isn't important for home use. There are two
RF, Microwave, Antennas and Optics :: 06-12-2013 17:51 :: betwixt :: Replies: 14 :: Views: 904
Addingt capacitors will increase switching losses, at least for a standard (hard switching) converter.
Power Electronics :: 07-24-2013 14:22 :: FvM :: Replies: 3 :: Views: 256
You need stiff current drive for hard switching, but if this
is an analog function (closed loop follower, or some such)
I recommend that you turn the limitation into a virtue,
put your frequency compensation at the weak node
(perhaps using an uncompensated or non-unity-gain-
stable op amp to recoup some bandwidth and simplify
the comp / stability
Power Electronics :: 09-03-2013 13:36 :: dick_freebird :: Replies: 4 :: Views: 274
The scheme used NJFET diff pairs and wasted current away
from the R-2R ladder into VCC for bits that were "off". The
signal swing required was a couple of hundred mV and was
applied to the "wasting" device gate, so the "active" bits'
gates were pretty much static - no movement, nothing to
settle. Unlike hard-switching the JFET (a volt or more, VPO)
Analog Circuit Design :: 12-04-2013 21:31 :: dick_freebird :: Replies: 4 :: Views: 159
My first comment is a general one. I'm missing a requirement specification. Without it, nobody can rate the discussed design ideas.
Assuming typical audio signal quality requirements, VGA810 won't be ever used.
Secondly, the standard solution for the addressed problem is a diversity receiver which switches the IF signal.
To avoid permanen
Electronic Elementary Questions :: 01-30-2014 07:22 :: FvM :: Replies: 14 :: Views: 569
According to my understanding if i use higher rated device and fault occurs,then hard switching will not be a big problem and device will not be in much stress in those i right here ?
hard switch-off of shorts can be a problem due to generated overvoltages. It's usually not a problem in bridge topologies with low indu
Power Electronics :: 02-07-2014 01:36 :: FvM :: Replies: 7 :: Views: 564
The 20 kHz rating is for regular hard switching applications with rated IGBT current. The induction heater application uses higher frequency but only a fraction of rated current and in addition a resonant load which can at least partly achieve ZCS operation..
Power Electronics :: 03-19-2014 18:20 :: FvM :: Replies: 3 :: Views: 324
FGA25N120 being used in Induction Cooker is the cheapest 1200V IGBT available in the Indian Market. However in hard switching applications it may fail. So if you are not using it in resonant applications think twice. At that switching frequency I would have gonr for the IRGC series perhaps and try with replacement IGBTs once other issues are (...)
Power Electronics :: 07-16-2014 01:14 :: andig :: Replies: 3 :: Views: 452
I'm building a prototype 37V-350A inverter welding machine. Currently i'm using Full bridge topology and hard switching (with 2 PWM control signals, one for LEG A, One for LEG B). Rectified 3 phase AC is connected as main input voltage. switching frequency is 31250 Hz. (32 us period). my Main controller is an ARM processor that (...)
Power Electronics :: 08-07-2014 01:51 :: memarian :: Replies: 0 :: Views: 207
switching Regulator Design (SRD) is a program dedicated to support the first phase of the DC-DC converters design based on the STMicroelectronics monolithic integrated regulators.
This tool is a guideline for the selection of the switchable device and of the main external components. The user is guided by a context-sensitive help and at the end
Software Links :: 11-01-2003 05:22 :: Robin Hood :: Replies: 0 :: Views: 883
what does hard-wired mean conceptually?
Electronic Elementary Questions :: 10-23-2004 02:58 :: vaf20 :: Replies: 6 :: Views: 2142
Audio applications are also sensitive to noise application. switching regulator are hard to control noise especially in large variation in loading.
Analog Circuit Design :: 09-28-2005 08:50 :: Rayengine :: Replies: 10 :: Views: 1482
yes the switched is matched, I've already put hard wired transmission gate in the series for the switched to trigger the node to output I've use all same value of transistor size ratio....
I didn't understand what do u mean by large enough? can u please tell me...
Analog Circuit Design :: 01-16-2006 21:29 :: Syukri :: Replies: 4 :: Views: 973
Well, it is hard to answer this question because I really don't know where your noise is. Are you getting noise across the drain-source of your MOSFET? Do you have oscillations at the output? Stability issues? Load transients causing poor regulation?
One thing you probably need to do is the make sure that you use snubbers across the switching tr
Analog Circuit Design :: 02-12-2006 00:06 :: v_c :: Replies: 1 :: Views: 2219
It is hard to predict by simulation, since it is mainly depends on the layout. If you can do the RC extraction of the layout. You can do a better calculation for switching loss.
Analog Circuit Design :: 03-13-2006 08:58 :: kwkam :: Replies: 7 :: Views: 15488
You will get maximum gain if the LO signal produces hard limiting. You will get the minimum of mixing products if the LO signal produces more linear variations.
Analog IC Design and Layout :: 06-26-2006 17:07 :: flatulent :: Replies: 4 :: Views: 834
here it is
YouTube - hard Disk BLDC motor driving circuit using PIC16F876A
Microcontrollers :: 09-11-2010 02:39 :: hameeds01 :: Replies: 11 :: Views: 13227
todays restoration tip when reworking wafer switches / pots / tracked switching devices etc
that are silver plated or are badly tarnished
there is a good way to do it i found
hot air and FLUX paste or ' no clean ' type is better
no clean type comes as a pen for application
or a brush and liquid type
some pots you cant take apart and waf
Service Manuals, Requests, Repair Tips :: 07-26-2009 05:18 :: VSMVDD :: Replies: 0 :: Views: 558
Circuit switching is used in telephone networks,, when the internet was first designed (ARPANET) they tried to find a more flexible way of connecting the devices.
In circuit switching each time two devices want to communicate they'll have to use signaling in what is called a call setup phase to establish a connection and then a circuit is reserve
Network :: 11-23-2009 05:31 :: asoom :: Replies: 4 :: Views: 1050
The only way it can be made to work is if the LEDs are on when the opto-isolator LED is OFF. Then you will have to carefully select R2 and R3 to avoid blowing up the MOSFET by exceeding its maximum gate voltage and also not blowing up the opto-isolator. You will need to drive the opto LED pretty hard to get the MOSFET to turn off, depending on the
Analog Circuit Design :: 07-03-2010 06:37 :: keith1200rs :: Replies: 11 :: Views: 1590
This is should be on the same thread as you posted yesterday, should it not? It is hard to follow if you post the same issue on multiple
Analog Circuit Design :: 09-15-2010 03:06 :: ejeet :: Replies: 4 :: Views: 1243
I have the good fortune to be trying to simulate some
"digital" circuits in a fairly old 40V bipolar technology. The
only models I have are for a near-minimum transistor in
Now I've been searching for info on how to model saturation
recovery time and coming up empty. This is probably the
most important, as well as most variabl
Analog IC Design and Layout :: 12-17-2010 12:03 :: dick_freebird :: Replies: 1 :: Views: 486
why dont you select one and lay your hand on it ?to regulate 6v-9volt input with output of 1.2-3.3v it's not that hard to regulate their are many regulators that can give more than 3Amps.
Power Electronics :: 01-10-2011 00:05 :: kabiru :: Replies: 2 :: Views: 884