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    Help me configure Center Tap transformer in proteus,

    Isn't there a Proteus User Forum? Look at the company website, as well as at Google, Yahoo, etc. I agree, the Proteus window you linked does not seem to address a multi-winding or tapped transformer. Meanwhile, I hope the moderators don't thump you for starting multiple threads on same...
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    Help Me Understand This Inverter Circuit

    The Dropbox links worked for me. But I can't really read the text on the schematic. Are the resistors 2.2k ohms? We r do need to know more about your objectives before trying to answer your questions. See my previous questions, above. If there are no requirements at all, we could assume...
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    protection for static relay

    I have been down this road, but it's been a few years. An inductor large enough to protect your triac may reduce the load voltage too much at the normal current. There may be problems getting the triac to turn on and turn off if the overall load is too inductive. Some sort of snubber may be...
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    Help Me Understand This Inverter Circuit

    Steve is correct, the pictorial diagram omits one of the battery connections. This sort of circuit has plenty of issues, but it has been much used over the years. You can learn more by looking-up "Royer oscillator". See the Wikipedia entry. Are you building hardware, or just making a...
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    electrolytic capacitor polarity help

    Think again. If you cannot figure out how this circuit works, you might look at the voltage across the electrolytic cap with a scope. If you lack test equipment, there are free simulation packages to be found online. The circuit in the posted schematic will definitely apply reverse bias to...
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    electrolytic capacitor polarity help

    You are correct, the electrolytic capacitor does see reverse voltage for part of the time during each cycle. The maximum reverse voltage across the capacitor will be limited by the 2N3906 Vbe as this transistor begins to turn on. Under 0.7V at room temperature. During the time the NPN...
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    Design of isolated buck converter

    I believe that by definition, a buck converter provides no galvanic isolation. To get your isolation, another topology must be chosen. As soon as a transformer is introduced, it's no longer a buck converter. The problem is that in a buck converter, part of the output current is provided...
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    What diode is used in this schematic?

    Kenneth, You can use a resistive voltage divider to reduce the gate voltage to some fraction of the input supply voltage, but then the gate voltage may be too small at lower supply voltages. If you add a resistor to limit the current, and a zener diode to limit the gate voltage, the circuit...
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    Can any body help me in making dual 24 Volt 5 amp Regulator??

    Prashant, Perhaps you can do what you want with the 7824 / 7924 devices. There are some advantages, and also disadvantages to this approach. I expect you might need 8 to 10 of each P/N to supply your 5A reliably. These devices may be paralleled using balancing resistors, but the result is...
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    Replacing a 9Vdc relay with a transistor switch

    Tim, It might help us if we had a clearer version of your schematic. You might try posting a version with better resolution. I think that there is some limit to images that appear right in the post, but other threads include examples that seem much clearer. Another approach is to put the...
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    What diode is used in this schematic?

    Kenneth, The last circuit posted will apply the full Vin voltage to the gate of the AO3041. Better keep it well under the 12V maximum rating of the part. Some protection on the gate's a good idea in any case, and 20V rated parts are not hard to find and cheap enough. I'm not sure what you...
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    What diode is used in this schematic?

    Kenneth, Thanks for the link to a data sheet. For some reason it didn't work, but it did ID the manufacturer, Alpha-Omega, and I found a datasheet for the AO3401 on their site. Unless you have located a particularly handy source for these parts, you might want to consider something you...
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    What diode is used in this schematic?

    Kenneth, I said "And, if you have a link to an online schematic, that would save the rest of us some time.", when I meant to say "data sheet" for the new P/N FET! Vgs is a condition, not a characteristic of the device. The -1V figure "could" be a breakdown voltage, the voltage where the...
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    What diode is used in this schematic?

    Kenneth, It's not clear what you might intend to do with the AO3401. Perhaps you can fill us in. And, if you have a link to an online schematic, that would save the rest of us some time. Going back to the manual on / software off application, I think you can easily modify the posted...
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    What diode is used in this schematic?

    Kenneth, Have you considered using your power switch transistor to switch the power-up current? If you do this, the manual switch, and any isolation diode, need only carry very small currents. I'm reasonably sure that the processor I/O pin over and under voltage maximum current limit...
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    Looking for help in designing circuit with lnk306

    Raf, It seems that we are not being very helpful to you. I feel that I don't know enough about what you are trying to do to be able to offer useful advice. I have no idea what a light switching scenario might be, nor medium or heavy-duty switching scenarios, for that matter. You might try...
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    Newbie: Help wiring 7 segment display

    Arthur, Thank you for linking the datasheet for your display. If someone wants pictures, Amazon is selling these things. The manufacturer is Maxx Tronic in Thailand. If I understand correctly, this module consists of a printed circuit board, 73 LEDs, and some resistors. The display does...
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    Looking for help in designing circuit with lnk306

    Raf, If you can, it's helpful to provide links to information that EPF members will need to answer your questions. The person who may best be able to help you may not have time to go try to locate this information. I'll try to help with this: The Lnk306 is a product of Power Integrations...
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    Sensitive photodiode circuit help

    Rossco, +1 on the need for a schematic! And it would help if you shared some basic information, such as required response speed, light levels to be detected or measured, etc. I suspect you have a mismatch between what you are trying to do and the IC you are using. The AD8015 is all...
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    Microwave Transformer Isolation

    Most consumer microwave oven transformers follow the same plan. The primary is completely isolated from the secondary and the core. They are not autotransformers. The primary winding is a physically separate winding, with a considerable space between it and the secondary winding. The...
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