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    Project design help (gates, d-latch questions)

    Maybe there is a different way to look at this problem. We have the occurrence of a sequence of logic signals and need to reach the end of the sequence without an error condition. I would propose a functional device, call it an Error Sequence Block, that can be wired in sequence to search for...
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    MOSFETs that make you scratch your head..

    While it is possible to have damaged the MOSFET gate during assembly of that rat's nest of wiring, what happens if you connect the gate and source together directly? If that causes a complete shutoff then the MOSFET is probably OK. In that case use a voltmeter to measure the signal voltage...
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    Calculating voltages help

    Sometimes it helps to redraw the circuit in a more familiar orientation..... If you have learned about voltage dividers, now may be the time to divide some voltage!
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    require help in wave theory

    The other moderator might be more understanding! i.e., Harald Kapp (Germany; Europe; Earth; Sol System; Milky Way; Laniakea)
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    Capacitive Reactance Circuit

    What should be obvious is that the reactance of Cin will always be ten times less than the added shunt capacitor at any frequency, so that the greater part of any transient will always flow through Cin. If you need transient protection then add some inductance in series with Cin (possibly a...
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    Capacitive Reactance Circuit

    So do a progression: What would be the reactance of each capacitor at 120Hz? 600Hz? 6kHz? 60kHz? At what point would the 47nF capacitor overpower the the 0.47µF capacitor?
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    Capacitive Reactance Circuit

    So essentially what you did was to add a 0.047µF capacitor in parallel with a 0.47µF capacitor and expected to see a large effect. If you added a 0.47µF capacitor instead, then I would expect to see ~6dB attenuation of the disturbance.
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    random signal generator

    A microcontroller would be a good approach if you are proficient in that area or wish to become proficient. Otherwise, a 4-bit binary counter and 4-to-16 line latched decoder (CD4514) is fairly simple. Running the counter from a high speed clock and latching the count with a pushbutton will...
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    require help in wave theory

    If a physical particle were to be held by a wave, then the particle would travel at the same velocity as the wave. Can you see any problems with that concept? What is the energy required to propel a particle with mass to the speed of light? A wave can travel through material with some degree...
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    Theory of operation of MS3110 high resolution capacitive sensor

    As you know the available explanation of the MS3110 theory of operation is rather sparse. But it does refer to a capacitive trans-impedance amplifier, although it is not clear how switching the voltage polarity across the sense capacitor is current-limited. What is not clear is how timing...
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    Theory of operation of MS3110 high resolution capacitive sensor

    Here is the portion of the datasheet block diagram with the switching portion highlighted. On the physical package there are multiple pin-outs for VNEG shown which suggests that VNEG is the system ground.
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    Theory of operation of MS3110 high resolution capacitive sensor

    I don't believe you are given enough information to derive the transfer function. The input is a change in capacitance and the output is a voltage. But this is a switched capacitor circuit where the capacitors are switched between Vneg and a 2.25V reference voltage under some sort of timing...
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    Capacitive Reactance Circuit

    I tried calculating the power in R1 the old-fashioned way with phasors, assuming that the diodes provide an AC short circuit and R2's effect is negligible. So the circuit reduces to XC1 & R1. The phasor angle is atan(-5644/470) = -85¼° so the RMS voltage across R1 is 120∙cos(-85¼°) = 9.96V...
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    AC analysis of common base BJT

    Here is my attempt at analyzing the common-base amplifier using the simplified hybrid-pi model. I don't remember ever having done this before as common-base is rarely used except for high-frequency RF circuits. Initially tried using Vπ from the model in the node equations but switched over to...
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    require help in wave theory

    Given the quantum mechanics principle of wave-particle duality, it might first be appropriate to consider when a wave is a particle, and when a particle is a wave. Much interesting reading can be had by searching for "electromagnetic wave particle interaction".
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    Help with De Morgan's theorem

    Here is a simple example of how to visually modify a logic circuit. The portion highlighted in red shows the substitution from AND gate with negated inputs to OR gate with negated output, as derived from DeMorgan using double negation. I believe the visual method is best to get from /(/A./B)...
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    Help with De Morgan's theorem

    I don't quite understand how a track sensor is able to turn another track sensor ON or OFF. Is this a combinational logic or a sequential logic problem? If it is combinational then you should generate a truth table. If it is sequential then you should generate a state diagram or next-state...
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    AC analysis of common base BJT

    Remember when you learned about imaginary numbers, how to perform manipulations in complex algebra, and how to calculate the magnitude and phase of complex variables? Well, a problem like this is where you use all that learning. Start by representing the capacitance and inductance as imaginary...
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    Help with De Morgan's theorem

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    School Project : Weighted Timing Controller

    Is the MAX/MIN OUTPUT a transient that needs to be latched, or is it permanently set while the counter output is all ZERO (while in down-count mode)? It does not seem that the counter would stay at any non-zero value until the next load signal. Also, if using CTEN` to start/stop the down...
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