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Driving high side back-to-back MOSFETs

Driving with single transformer isn’t possible? For 100kHz the core size can be very small like 15mm ferrite ring with about 3x50 turns.
Michal Podmanický's user avatar
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Driving high side back-to-back MOSFETs

You seem to be wanting a fast switching solid state relay with back-to-back MOSFETs. Have you looked into this? Would that meet your needs (other than for the switching speed being too low)? – Andy ...
Andy aka's user avatar
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1 vote

FETs in Push-Pull Converter Keep Blowing, Not Sure Why

If we take the BSC040N10NS5ATM as an example. The total gate charge figure could be as high as 72 nC. If we divide this by the gate voltage specified in that parameter (10 volts), we get an effective ...
Andy aka's user avatar
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The 15 V valve not driven by an IRF3205

The IRF3205 has a VGS(th) of 2 to 4 V, according to the datasheet. This threshold voltage is where the MOSFET just starts conducting, in the order of 250 μA (also see How important is the gate ...
ocrdu's user avatar
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How can I protect a MOSFET from high voltage spikes in a DCDC converter?

OK. I made this thing. It's a low voltage buck chip with a cascode. It's a bit unconventional, because it's somewhat upside down. How it works: Q5 is the power-on switch. When it receives base ...
bobflux's user avatar
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How can I protect a MOSFET from high voltage spikes in a DCDC converter?

Adding to other answers (without repeating what they say), I believe implementing a soft-start feature would be beneficial. The TL494 data sheets shows how this can be done: - You might also choose ...
Andy aka's user avatar
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How can I protect a MOSFET from high voltage spikes in a DCDC converter?

So, Starting from 100V, then increasing to 190V: it works Starting from 190V: it burns. As Russel says, the FET is not well chosen for this application, max Vds is too low and RdsON is too high, ...
bobflux's user avatar
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3 votes

How can I protect a MOSFET from high voltage spikes in a DCDC converter?

I assume that the FET shown on the diagram is what you are using. If not, you should at least say so in the text and ideally change the diagram. Regardless of the specific failure reason, you are ...
Russell McMahon's user avatar
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I want to run the high side switch without using the bootstrap

This is quite a common solution for half-bridges that can't use a normal bootstrap circuit (i.e. ones that need to reach 100% duty cycle). It'll work perfectly fine. You can save a few components (and ...
Jonathan S.'s user avatar
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How to mitigate this transient with huge magnitude at turn on interval for a MOSFET tested in double pulse test setup In LTspice?

Q1 gate output is low, so Q1 is not in the circuit at the start. The current climbs to about 40 amperes, and when you shut off the gate, the inductor will cause V_DS_DUT to increase until the ...
John Birckhead's user avatar
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High side switching without bootstrap driver circuit

There is also possible to switch N-ch from isolated power-supply (like 10 to 15V) or battery. Its Gnd is connected to Source of mosfet. So this additional power source is “flying” according Source ...
Michal Podmanický's user avatar
2 votes

Controlling a IR2110 with PFM for Half Bridge Circuit

Is your concern at the low frequency end of PFM operation? The IR2110 has a quiescent current into the boost pin, so that will be one consideration in sizing Cboot. The PFM mode will need a minimum ...
JkingNH's user avatar
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0 votes

Overheating MOSFET fix, find right gate resistor

R4 is fine with 10K (you can go as high as 50K). The problem is with R5. Resistors to ground should be at least 100K. In this case Q3 Gate is not fully on because too much voltage drop through R5. ...
Fredled's user avatar
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1 vote

Double Pulse Schematic

Do I need to connect the source pin of Q2 to VDDB? Short answer: no. Longer answer: Doing this connection would connect pins 1 & 2 of J3 across R3. I suspect R3 is a very low-value resistor (its ...
Fabio Barone's user avatar
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0 votes

Need gate driver for MOSFET (IRF540) and microcontroller

I ran a perhaps simpler maybe simple circuit- from MCU - use DM 7407, a 7812 for power, open collector on 7407 pulled up with 1K ohm resistor to +12 VDC...IRF-540 or 541 being tied into +24 VDC for ...
Fred Mitchel's user avatar
2 votes
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Can I power LEDs of different forward voltages connected in parallel with a single constant current source?

This isn't going to work. With the schematic you posted, only the yellow LEDs will light, all others will remain dark. The yellow LEDs will also get horribly overloaded and burn out. What matters isn'...
Jonathan S.'s user avatar
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1 vote

Transmitting PWM over a long cable, how to prevent ringing?

I want to transmit three 5V 32kHz PWM signals, with fast rise and fall times (approx. 10ns) That's a bit of a "doctor, it hurts when I do that" situation. There's no good reason to send ...
Kuba hasn't forgotten Monica's user avatar
1 vote

Transmitting PWM over a long cable, how to prevent ringing?

Of the two examples you gave, I would use the latter. The resistor in that case can be sized to dissipate a lot less power. However, as alluded to by sina bala, the a filter or RC termination at the ...
Ryan's user avatar
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2 votes
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Transmitting PWM over a long cable, how to prevent ringing?

I want to transmit three 5V 32kHz PWM signals, with fast rise and fall times (approx. 10ns), over a 2m long, 4 wire telephone cable At a rise time of 10 ns, we're talking of a bandwidth of at least ...
sina bala's user avatar
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