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  1. Closed: Re: Input LC filter inductor is being shorted out

    I suspect the damping is desired for more than start up transients. Simulate their network and see how the bode plot looks.

    To damp transient and fault scenarios I’ve clamped inductors with...
  2. Closed: Re: Phase detector with synchronous logic (FPGA)

    I'm familiar with doing phase detection in FPGA's (DFT or 'sin correlation') as suggested. The math is easy (multiply and accumulate versus sin and cos, do some algebra with the accumulator...
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    Closed: Re: Circuits for P, PI and PID controllers

    P is just a gain stage
    I is an 'integrator' google for examples of opamp integrators
    D is a 'differentiator' google for examples of opamp differentiators


    Also understand how PID maps to common...
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    Closed: Re: Fast amplifier using one stage OP AMP

    Great problem to explore in a simulator like LTSpice which has good models for almost all Analog devices (Linear) opamps covering all types and bandwidths.

    There you can see how well they can...
  5. Closed: Re: The "cheap, quick and easy" way to do high power SMPS's?

    Ok then.

    Ideally you’d phase shift them for interleaving.
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    Closed: Re: Recommendations for Beginner

    I don't think there is a big difference in price between similar Xilinx/Intel parts.

    On the other hand Xilinx doesn't compete on the low end against Max10 (intel) or MachXO (lattice)

    I've used...
  7. Closed: Re: Heatsinking for Vicor DCDC modules on a test PCB?

    Vicor sells heatsinks for its packages:

    http://www.vicorpower.com/accessories/thermal-management
  8. Closed: Re: The "cheap, quick and easy" way to do high power SMPS's?

    My starting point would be to choose a current mode controller/topology and, as we've discussed elsewhere, you can then have one voltage loop driving as many inner current controllers as you want. ...
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    Closed: Re: Bias current sensor for floating earth

    Think of it this way: There is no such thing as 'floating'. Any two points on earth have some amount of resistance and capacitance between them.

    And all isolated power supplies have R and C...
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    Closed: Re: Bias current sensor for floating earth

    So you're looking to detect a ground fault where either your DC link positive or negative is shorted to earth?

    You can directly measure the voltage of either node to Chassis and see if one is...
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    Closed: Re: Off-line Power factor correction

    I'd just understand it as a general problem where the system has a step change in its performance on the boundary between CCM and DCM.

    Although feedback loops theoretically solve this in real...
  12. Closed: Re: Silicon carbide FETs best for Phase shift full bridge?

    I haven't seen any PSFB design, demo or reference that fully ZVS's at no load. I think you have to be able to tolerate hard switching. If you use GAN or SiC its no problem.

    This infineon talks...
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    Closed: Re: Vicor Bus Converter module

    One major question: Why parallel all of them when you probably have 4 or more motors? Give each motor its own bus rather than sharing a single gigantic one.
  14. Closed: Re: Charge injection in chopper-stabilized opamps.

    I had TI in house talking about this stuff a few months back and they think you should still be careful but that modern parts like OPA189 have almost solved these problems. The 189 spec says:
    ...
  15. Closed: Re: Silicon carbide FETs best for Phase shift full bridge?

    I don't understand how PSFB is more vulnerable than standard full bridge. What I think is you see articles say "watch out for RR!" because you might otherwise forget in a PSFB. I said exactly that...
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    Closed: Re: Vicor Bus Converter module

    Call Vicor and let us know. I've talked to them about paralleling although I hadn't latched onto this particular spec to ask about specifically (my mistake).

    As mentioned I recall finding...
  17. Closed: Re: Precision op amps - is 1 microvolt offset believable?

    Yes, in a chopper or zero drift opamp. They use various switching architectures that can theoretically cancel all offset and drift. The switching comes with some downsides however - usually...
  18. Closed: Re: Intrerleave wind transformer on Phase Shift Full Bridge converter?

    Makes sense to me. External inductance allows the clamping diodes, it's also easier to control and modify if its separate. Note that it gets wacked with both high voltage and high ripple...
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    Closed: Re: Vicor Bus Converter module

    Ok fair but consider the same thing is true for any mosfet yet we parallel them all the time with the expectation of better than 2:1 sharing. Steep Rdson thermal gradients are one reason this works....
  20. Closed: Re: Phase shift full bridge controller datasheet gives misleading info?

    Additional parallel or series inductance? Only parallel inductance could ensure ZVS at very light or no load (while adding circulating current losses).

    Gan or SiC is helpful to deal the light...
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    Closed: Re: Vicor Bus Converter module

    No, that's likely thermal variation just as a mosfet has widely varying Rdson yet is widely considered appropriate for paralleling.

    You're citing a Vicor document which details how to parallel...
  22. Closed: Re: Phase shift full bridge controller datasheet gives misleading info?

    Adaptive delays help you balance ZVS operation with dead time diode conduction losses.

    On a super quick look they tie the ADEL (adaptive delay) pin to the current sense so dead time can change...
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    [SOLVED]Closed: Re: Auto oscillating DC-DC converter

    I think its still common for small isolated DC-DC's like this 1W part:

    https://www.digikey.com/product-detail/en/murata-power-solutions-inc/NXE1S0505MC-R7/811-3040-1-ND/5047366
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    [SOLVED]Closed: Re: Auto oscillating DC-DC converter

    Also "Royer oscillator"

    https://en.wikipedia.org/wiki/Royer_oscillator
  25. Closed: Re: Vicor Power Module to power a BLDC & inverter.....inrush at startup?

    I might expect intelligent brushless controllers can limit start up current.

    I see a 40A pulsed current rating.

    Output filter design can also help, but see the 450U C limit.

    I can speak...
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