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Type: Posts; User: FvM

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    Closed: Re: Schematic circuit plot from Cadence Virtuoso

    You need to install the Microsoft HPGL import filter for word, review Microsoft help.
  2. Closed: Re: Full Bridge DC-DC Converter Operating Frequency

    For usual switching patterns (simple push-pull, phase shifted bridge), 10 kHz transistor switching results in 10 kHz transformer and 20 kHz output frequency.
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    Closed: Re: RC HPF filter noise?

    A 40 - 200 kHz HPF for an audio signal? Seriously?

    Apart from this point, it's useless to discuss noise and THD without considering the signal level. Also source and load impedance play a role.
    ...
  4. Closed: Re: How to find Inductance/length given an s-parameter of a transmission line?

    The question is somehow incomplete. What is "an s-parameter"? S11? A single frequency S11 value can be directly converted into an RL or RC parallel or series equivalent circuit. But I guess that's...
  5. Closed: Re: TRIAC Phase Firing Circuit Simulation using LTSpice

    Thanks for attaching the Ltspice file, you should also append a schematic screenshot for convenience. Current limiting resistor is surely missing.

    159690

    A zero crossing circuit like this has...
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    Closed: Re: Frequency Module IGBT

    30 kHz is no exact specification, it's an estimated value that can be achieved unter certain conditions. If you make a quick calculation of switching losses, you'll realize that 30 kHz can't be...
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    Closed: Re: Frequency Module IGBT

    Not sure how you calculate "load switching" frequency. In case of unipolar modulation scheme, output pulse frequency is double the PWM frequency. But that's not relevant for transistor switching...
  8. Closed: Re: TRIAC Phase Firing Circuit Simulation using LTSpice

    I see several issues with your simulation.
    1. The models are corrupted, You have apparently edited the subcircuit port names. I reverted to the original MOC3021 model from by Helmut Sennewald and...
  9. Closed: Re: TRIAC Phase Firing Circuit Simulation using LTSpice

    In a short MT1 and MT2 should be flipped.

    Testing and correcting your simulation setup would be much easier if you zip the *.asc and *.lib files and append it to your thread.
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    Closed: Re: Interfacing GSM Sim900a with PIC16f887

    Is the modem setup for 115k? If not, tx_str("AT\r\n") doesn't achieve autobaud, you have to send "A" and "T" with pause after each character.

    Generally, it's difficult to debug modem code sending...
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    Closed: Re: Stuck at simulations of Amplifier in LTSpice

    Capacitors are zeroed during initial transient solution, thus a SPICE simulator has no problems with large capacitors, as long as the large signal operation point doesn't differ from the initial...
  12. [SOLVED]Closed: Re: 16F877A : TMR1L/H, can not load values inside with sprintl

    I don't recognize that interrupts are ever started in the post #1 code.

    Shouldn't main() call the init functions?
  13. Closed: Re: Magnet core inductor out of TV set, what is is used for?

    Thanks, a ferrite permanent magnet glued to the top of the drum core, probably a second one at the bottom. I agree, it can be hardly used for anything besides it's original dedication.

    Expect only...
  14. Closed: Re: Magnet core inductor out of TV set, what is is used for?

    The photo in post #7 seems to show a simple coil with ferrite core. Are you sure that it involves a permanent magnet? Due to the open magnetic path, the core has only limited effect on the coil...
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    Closed: Re: Frequency Module IGBT

    I can't imagine many configurations where the switching frequency per module is higher than per transistor, anyway the datasheet specification is surely per transistor. But the number gives only a...
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    Closed: Re: Photodiode SFH205FA in PSpice

    Find photo diode models at https://www.osram.com/os/tools-and-services/downloads/index.jsp

    Basically a Si-diode + a current source to model the irradiation.

    The basic diode without the current...
  17. Closed: Re: Magnet core inductor out of TV set, what is is used for?

    "S" correction choke is a good guess, but there are many different magnetics, particularly in a color TV. It's about 20 years since I did the last CRT TV repair.
  18. Closed: Re: Huge difference between results from schematic simulation and momentum co-simulat

    I believe that you see large differences with the said "extreme" microstrip geometry. Unfortunately I can't locate a comparison of both results in your threads.

    Like Volker, I would trust the EM...
  19. Closed: Re: Magnet core inductor out of TV set, what is is used for?

    Why not show a photo?
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    [SOLVED]Closed: Re: Help for Assembler 12F675

    Sounds self-explanatory to me. It's Proteus.
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    Closed: Re: PWM Ramp Voltage of SG3525

    To calculate the modulator gain, you better refer to the typical rather than marginal threshold values, 0.9 - 3.3V.
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    [PIC]Closed: Re: Question About Crc8 Picbasic Implementation

    The answer was already given: Yes.

    That's how CRC calculation works, you initialize the CRC variable, call the routine for every message byte and have the message CRC.
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    [PIC]Closed: Re: Question About Crc8 Picbasic Implementation

    You need to review the PICBASIC manual. HEX2 means two hex digit formatting.

    In my view, the original question hasn't much to do with CRC algorithm. It's more general how to implement a specific...
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    Closed: Re: Current Density PCB track

    No. Small trace is dissipating most heat by lateral conduction, thus higher specific rating. Large plane must dissipate all heat vertically. By the way, radiation plays a minor role in heat...
  25. Closed: Re: DCDC module recovery from input overvoltage involves a time delay?

    Always a good idea to read the manual completely. Review page 13.
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