56 Threads found on edaboard.com: Hard Switching
What is wrong with hard turn-on and turn-off? The very large di/dt involved can couple with parasitic capacitances/ inductances and cause this spike.
Sounds rather vague and highly speculative. You're not actually saying how the waveform could be generated. There's no parasitic inductance present in simulation unless you are using p
Analog Circuit Design :: 02-08-2016 15:30 :: FvM :: Replies: 5 :: Views: 509
Are you really planning to run a hard switching IGBT inverter at 30 kHz?
Power Electronics :: 11-26-2015 22:52 :: FvM :: Replies: 13 :: Views: 1131
You can also add a snubber circuit near to each switching device.
This will reduce the peak current flowing inside during opening period.
Another possibility, but it's kind of hard to evaluate without a notion either of the waveform or the board layout, is that the transistor base is receiving induced noise, which could cause undesired DC drivi
Power Electronics :: 04-07-2015 17:42 :: andre_teprom :: Replies: 12 :: Views: 676
1) Gate driver IC has high output current for fast switching.
2) Opto's are used for isolation not for driving the gates.
3) It has been a long time since i looked at this issue but there were several reasons at the time. P type mosfets were hard to buy in higher current and voltage, and they were more expensive. Also you can easily turn the P ty
Power Electronics :: 03-25-2015 19:25 :: FlapJack :: Replies: 2 :: Views: 416
Your "switching frequency" depends on whether (or how
hard" you will saturate the device along with the working
temperature. A switching transistor may have a datasheet
recovery time spec. A linear one may not bother and all
bets are off. One that does offer a turnoff time spec may
only do so at one test condition, while your load (...)
Analog Circuit Design :: 03-20-2015 18:40 :: dick_freebird :: Replies: 10 :: Views: 731
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 05:51 :: memarian :: Replies: 0 :: Views: 751
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 05:14 :: andig :: Replies: 3 :: Views: 1591
Thanks for reading this. Although reverse polarity protection is easily findable on searching the forum and on Google etc.. The specifics of my project makes it hard to apply most of the common results from such searches to what I want to do. In short, the circuit has a high power switching P-Channel Mosfet directly between VCC, load and Gro
Power Electronics :: 07-08-2014 17:46 :: Zaprooder :: Replies: 14 :: Views: 1645
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 06:36 :: FvM :: Replies: 7 :: Views: 1376
As we have no idea what the expected switching rate/frequency is in your application, it is kind of hard to suggest a value, but a simple low pass RC filter on the input should do it - if the wiring is going out to mechanical switches/relays, you should probably have some filtering and/or transorbs or clamping diodes on the inputs anyway to prote
Embedded Linux and Real-Time Operating Systems (RTOS) :: 01-14-2014 17:08 :: ftsolutions :: Replies: 4 :: Views: 701
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 17:36 :: dick_freebird :: Replies: 4 :: Views: 493
Addingt capacitors will increase switching losses, at least for a standard (hard switching) converter.
Power Electronics :: 07-24-2013 18:22 :: FvM :: Replies: 3 :: Views: 439
You would expect the hard (faster?) switching converter to be more efficient than the soft (slower?) switching due to lower switching losses. So what is your concern?
I guess, this describes the problem of the present "soft switching" design. But it's not what soft switching usually means. (...)
Analog Circuit Design :: 03-24-2013 08:44 :: FvM :: Replies: 4 :: Views: 576
Your posted circuit doesn't look to have much dead time for the push pull circuit, that is naturally provided by the Royer circuit, this may well give you hard switching and more "noise"than you are seeking...especially as you have removed the resonating cap across the transformer ends...
Power Electronics :: 02-25-2013 06:37 :: Orson Cart :: Replies: 7 :: Views: 2367
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 :: 02-24-2013 04:32 :: goldsmith :: Replies: 2 :: Views: 640
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 22:20 :: mtwieg :: Replies: 14 :: Views: 823
Without seeing a more detailed circuit it's hard to tell. How are you measuring the AC current in the LEDs and the regulator output?
Analog Circuit Design :: 02-16-2013 04:53 :: mtwieg :: Replies: 7 :: Views: 811
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 16:15 :: FvM :: Replies: 1 :: Views: 1408
....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
Elementary Electronic Questions :: 02-04-2013 07:11 :: treez :: Replies: 0 :: Views: 880
From desired Vce(sat) you can (I expect) determine a
"forced beta" operating point and from that and load
(plus margin) determine the required base current.
Hopefully this does not exceed pin ratings of the uC.
Then your desired resistor is VOH(min)-Vbe(max@)/Ib.
If you saturate it real hard then switching (off) delay
will be compromised and if y
Elementary Electronic Questions :: 01-25-2013 18:06 :: dick_freebird :: Replies: 5 :: Views: 1085
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 14:57 :: FvM :: Replies: 19 :: Views: 1038
With a linear regulator, at 16v input and 4v output at 2A, you would be dissipating 24W of heat, do you have a heatsink for that?
You need a switching converter, and that is hard to do for 2-3USD.
Power Electronics :: 08-13-2012 12:17 :: sky_123 :: Replies: 1 :: Views: 882
If it is not switching on it must be SMPS problem.
If it is switching on powering OFF in BIOS window it might be due to corrupted hard Disk.
Go to service centre and get the respective replacement.
Service Manuals, Requests, Repair Tips :: 06-10-2012 09:06 :: Prashanth.vinnakota :: Replies: 1 :: Views: 858
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 22:09 :: FvM :: Replies: 2 :: Views: 702
MOSFET switching - Turn-ON, hard switching
SpringerLink - Technical Physics, Volume 51, Number 5
Power Electronics :: 08-30-2011 06:15 :: raksha singh :: Replies: 1 :: Views: 1415
You need to increase sinking capability for gate driver to reduce switching off time.
However, it is hard to be symmetrical because turn-on time only needs to charge from 0V to NMOS's Vth and turn-off time needs to discharge from VDD to Vth.
For example, VDD=5V, Vth=0.7V, you can see the difference.
Analog Circuit Design :: 08-20-2011 09:24 :: leo_o2 :: Replies: 6 :: Views: 1050
Bulk capacitance needs to be charged and discharged. So there will be switching current.
It might be hard to reduce it.
Analog Integrated Circuit (IC) Design, Layout and Fabrication :: 06-08-2011 10:37 :: leo_o2 :: Replies: 3 :: Views: 1044
the mosfet gate turnon voltage is always in respect to its source terminal. So when the source voltage is at 4.5v and the gate is still at 3.6 it could already start turning on (logic level mosfet too ? ), so you drop the gate voltage to turn it on hard, sure it might not turn off then, no mystery there :smile:
You must level shift the gate
Elementary Electronic Questions :: 05-04-2011 12:13 :: xaccto :: Replies: 2 :: Views: 1051
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 19:38 :: Regnum :: Replies: 0 :: Views: 921
There is a class of synthesizers called "direct synthesizers" (not to be confused with DDS), that use multiple crystal or saw oscillators, mixed together in various ways with a switch matrix. They used to be very hard to make because the switching matrix was difficult, but they now have "crosspoint" video switches that can do stuff like 2:8 on a c
RF, Microwave, Antennas and Optics :: 01-24-2011 15:32 :: biff44 :: Replies: 4 :: Views: 661
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 05:05 :: kabiru :: Replies: 2 :: Views: 1134
I have special need that requires either some "high-speed" dual ported memory or a way to use bank switching of some static ram between two separate address/data bus systems. I am not finding any high-speed dual-ported memory, and I am having a hard time finding any specialized chip sets that might do the bank switching job. No doubt that is (...)
Microcontrollers :: 12-29-2010 18:02 :: slcoleman :: Replies: 0 :: Views: 482
Would there be a problem (like to the bulb, or the tungsten filament in the bulb) if a 40/60W bulb working with 240 AC flickers?
It's life-time will be surely reduced. switching between "dimmed" and on is more friendly to the filament than hard on/off switching, because most stress is caused by powering a cold filament. Stage light
Elementary Electronic Questions :: 12-05-2010 21:42 :: FvM :: Replies: 12 :: Views: 1201
Class-E amplifiers don't work in such a way...
They work always in switching mode so hard saturation mode, not linear or triode region etc...
For these kind of amplifiers, finding an input matching network is not easy task but a "rough approximated" circuit will serve,no problem.
Output L-C circuits are very important for efficiency,harmonic lev
RF, Microwave, Antennas and Optics :: 10-04-2010 21:52 :: BigBoss :: Replies: 2 :: Views: 868
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 09:43 :: ammarzouk :: Replies: 2 :: Views: 731
PIC devices are not hard to program as the actual device programming goes.
IF you meant are PICs hard to use that is also no.
Im pretty sure you wont be able to connect to your phone directly without either writing the code to manage the proper signalling protcol or using a seperate transceiver device.
Hobby Circuits and Small Projects Problems :: 03-11-2008 02:47 :: nxtech :: Replies: 1 :: Views: 2011
i think it all depends on the way the two signals are , like u want the switching MOSTs be hard switched so u need a large square wave for that (i.e. LO signal),so a small signal of the RF wont switch the pairs which wont give a good mixing and a very bad noise figure.
while usually u need a gain to the RF signal (usually small as it arrives weak
Analog Circuit Design :: 06-14-2007 09:46 :: safwatonline :: Replies: 2 :: Views: 948
switching would always induce noise i.e.glitch and it is hard to eliminate it completely... maybe you can smoothen it by using filters or reactive components....
Analog Circuit Design :: 07-15-2007 10:53 :: A.Anand Srinivasan :: Replies: 7 :: Views: 4013
Why do you want to build this? Most inverters today use high frequency switching techniques that may be hard for a beginner like yourself. Maplin sells a whole range at affordable prices.
The other alternative is a simple 50Hz square wave inverter using a bulky 50Hz transfor
Elementary Electronic Questions :: 03-26-2007 15:20 :: E-design :: Replies: 4 :: Views: 1129
Take a look at tis device. Maybe it can be used for your app.
...and Maxim MAX1555 too. Although be careful, it might be a little hard to obtain in production quantities.
Analog Circuit Design :: 03-15-2007 22:39 :: kender :: Replies: 8 :: Views: 3255
here it is
YouTube - hard Disk BLDC motor driving circuit using PIC16F876A
Microcontrollers :: 09-11-2010 06:39 :: hameeds01 :: Replies: 11 :: Views: 14796
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
Elementary Electronic Questions :: 07-24-2006 11:39 :: dtparekh :: Replies: 2 :: Views: 5782
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 Integrated Circuit (IC) Design, Layout and Fabrication :: 06-26-2006 21:07 :: flatulent :: Replies: 4 :: Views: 1065
This is very popular these days but it's hard to get the information.
Does anybody know how I can get the information about LED driver "IC" design?
Analog Circuit Design :: 04-13-2006 17:01 :: kdavid94588 :: Replies: 3 :: Views: 2388
Can anyone who is currently using PADS and Alegro tell me how easy or hard it is for a PADS user to learn the Alegro tool?
Also, give me some pointers such as what to look for or avoid when switching from PADS to Alegro.
Thanks in advance
PCB Routing Schematic Layout software and Simulation :: 04-09-2006 00:19 :: layout guy :: Replies: 0 :: Views: 1034
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 13:58 :: kwkam :: Replies: 8 :: Views: 33750
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 05:06 :: v_c :: Replies: 1 :: Views: 2811
I think this need a hard macro to receive data, in the ip don't need so fast , and the hard macro you need design and verify use spice , and the ip just need 1000M/8 or 1000M/16. by the way , the io of 1000M is very hard design.
ASIC Design Methodologies and Tools (Digital) :: 12-29-2005 12:00 :: xworld2008 :: Replies: 4 :: Views: 1091
It's hard to believe that a switching power supply introduced 50Hz ripple. Either the P/S is defective, or something else is going on.
Check the power supply with just a load resistor that draws as much current as your circuit. Measure with the scope the ripple across that resistor. It should be at the P/S switching frequency, in the (...)
Professional Hardware and Electronics Design :: 10-10-2005 17:45 :: VVV :: Replies: 4 :: Views: 2166
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 12:50 :: Rayengine :: Replies: 10 :: Views: 1812