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  1. D

    Question about op amp dual supply circuit...

    CMRR=20log10CMR Either will suffice for the discussion. Actually CM as a problem is point of discussion, the above of course actual measurements.
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    Power on a different board vs same board

    Tradeoffs, always tradeoffs : https://www.analog.com/media/en/training-seminars/design-handbooks/Practical-Power-Solutions/Section1.pdf Regards, Dana.
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    Opamp circuit clarifications

    There is a problem attaching a large cap directly to an OpAmp input, depending on OpAmp architecture. That is discharge of the capacitor when supplies are removed, can cause input stage damage, such as leakage current in jfet input opamps, and or damage in ESD protection diodes internal to...
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    Question about op amp dual supply circuit...

    CMR (and CMRR) is Common Mode Rejection and Common Mode Rejection Ratio : https://www.analog.com/media/en/training-seminars/tutorials/MT-042.pdf Item 3, Post #6 (stability) : https://www.analog.com/media/en/technical-documentation/application-notes/an-257.pdf...
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    Battery Protection from alternator.

    Of course jump start can also be an issue : https://m.littelfuse.com/~/media/electronics_technical/application_notes/varistors/littelfuse_suppression_of_transients_in_an_automotive_environment_application_note.pdf Regards, Dana.
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    Question about op amp dual supply circuit...

    I am thinking that circuit has some major problems : 1) Inputs are violating CMR for that particular OpAmp over significant ramp up[ of input power. 2) Output 22 uF sure to put it into oscillation depending on what other load is present. ua741 not known for driving any significant C load. 3)...
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    Battery Protection from alternator.

    The over voltage condition, is it pulse or more of a DC condition ? If pulse any details, like timing limits...... Pulse conditions possibly : https://www.littelfuse.com/products/tvs-diodes/high-power.aspx https://www.mouser.com/new/bourns/bournsPTVS/...
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    Basic Circuit Analysis

    Take equation 1, you are mixing current and voltage as terms and adding them together, eg. -3 + I1, you added a V to a current : You cant do a V loop on all outside branches because one branch is a current source and you cannot determine directly what its V to gnd is. So correct dual symbol I1...
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    Resetting Latching Relay with Momentary Button

    https://uk.rs-online.com/web/p/power-relays/5111098 ? Regards, Dana.
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    Output voltage higher than expected

    The PBSS306 on your schematic, is shown as NPN, yet the 306 is PNP ? The transistor should be NPN..... https://assets.nexperia.com/documents/data-sheet/PBSS306PZ.pdf Regards, Dana.
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    Output voltage higher than expected

    As Ib drops so does Vbe and as previously stated Vout = Vz - Vbe, so we have Vout rising : Regards, Dana.
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    Output voltage higher than expected

    Output is classic series regulated, and its open loop, so Vout = Vz - Vbe. Principal problem, as an aside, occurs at very high loads where R1 starts starving the pass transistor for base current and zener drops out of regulation. Note I cannot tell from schematic if there is fdbk from one of...
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    Laptop power supply's capacitor burnout

    Output C considerations : https://www.microchip.com/stellent/groups/sitecomm_sg/documents/training_tutorials/en528035.pdf Output and Input considerations : https://www.analog.com/media/en/training-seminars/design-handbooks/Practical-Power-Solutions/Section4.pdf Regards, Dana.
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    Input Hum - Yorkville Amplifier

    Curious, was OpAmp socketed ? Usually they do not fail. So asking maybe input pin was in poor contact with socket.... Regards, Dana.
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    How to use an H11AA1 optocoupler to make a missing half sine wave mains detector

    Using an opto coupler as a zero cross detector, stated another way when zero cross no longer occurs of line there is a power outage. Use that as an interrupt to signal line loss...
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    Education & Jobs in Electronics

    One excellent way of getting info like this is for the city/area you are interested in find local news paper, facebook groups, and see if their want ads are online. Of course you can always browse the myriad of job websites now present. This way you can see what qualifications are required...
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    DIY Kindle Remote Page Turner

    Here is a simple design where i had to control a remote hotspot by pressing its button remotely with a servo to bypass a blocking menu item. ESP8266 Nodemcu primary HW. And a servo connected to it. Code done in block language, Tuniot...
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    Protection of my loads (batteries + equipment) from alternator

    GE Scr Manual for crowbar circuits, section 8. https://archive.org/details/bitsavers_ge1972GESC_44892955 Regards, Dana.
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    Protection of my loads (batteries + equipment) from alternator

    Load dump in vehicles : https://www.ti.com/lit/an/snva681a/snva681a.pdf?ts=1689331020836&ref_url=https%253A%252F%252Fwww.google.com%252F...
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    Input Hum - Yorkville Amplifier

    If you touch a cap to either OpAmp output or its inputs, the other side to ground or supply V, good chance the OpAmp becomes an oscillator due to loss of phase margin. Regards, Dana.
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