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  1. C

    Diode Characteristic Graph

    As implied by the question and understood but, as mentioned, this is where I am totally stuck and looking for some assistance...
  2. C

    First order filter help

    Looking at the section of your link called "What is an example of 3 dB bandwidth estimated from rise time?" I believe that if I calculate my rise time, which is the time to go from a magnitude of 0.1 to 0.9, then I can relate this to my corner frequency (f3db). My rise time I calculate as...
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    Diode Characteristic Graph

    I wouldn't do this as the question is specifically telling me to use a diode.
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    Diode Characteristic Graph

    Then why am I being asked to use a diode as per the graph if I'm not supposed to be selecting component sizes? What I am getting at is... the question infers "use the graph" in my answer, but I am not using the graph because I don't understand how to relate the information of the graph to my...
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    Diode Characteristic Graph

    Without trying to sound ungrateful for the help, it isn't the circuit design I am struggling with. I have a circuit which works - perhaps by chance?! But what I am struggling with is that the question has asked me to use a diode which is characteristic of the information in the graph, but I am...
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    Diode Characteristic Graph

    Hi - Thanks, what I don't understand though is how that graph is telling me the diode size?
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    First order filter help

    Hi - thanks for the reply but I don't follow. The reason the 2.25 is divided by 10^-6 is so that it is in uS and balanced to the MHz side.
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    Diode Characteristic Graph

    Hi, I have a question on my course which is: 1) FIGURE 3 (on page 7) shows a PIR (passive infra-red) detector and its associated amplifier, as used in burglar alarm systems1. a. The detector is powered from a 12 V unregulated supply that needs to be stepped down to 5 V. Design a...
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    First order filter help

    Hi, I have the following question: FIGURE 2 shows the response of a first-order filter to a step input. Estimate the half-power cut-off frequency of the filter and sketch its frequency and phase response. My attempt at the answer is: The half-power cut-off frequency is when the voltage is at...
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    Sallen and Key Bandpass filter

    Hi, I have the following question, which I need some fundamental help with to get going: Design and PSPICE model a bandpass filter of ‘Sallen and Key’ topology and having the following characteristics: fo ~ 3.3kHz, Q ~2.2. Verify your design by means of a Bode plot. From my learning material...
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    Op-Amp Gain

    I have a question in which I have to compare the specs of two op-amps in a table to text descriptions and match them together. My question is, one of the descriptions states that the gain is 112dB. I believe this to be Op Amp A, as the description also states the PSRR is 120dB. How do I...
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    Op amp max frequency based upon slew rate and gain

    Thanks for the reply - I think I may have worded my question poorly. I have a given slew rate for my op-amp, I need to calculate the maximum frequency (power bandwidth) of the amp. The equation I want to use is: Fmax (Hz) = SR / (2 . Pi . V) This is where I'm struggling to find out the...
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    Op amp max frequency based upon slew rate and gain

    Hi, I have the following question in my HND... Estimate the maximum frequency of a sinusoidal input signal of 10 mV peak, for distortion-free output, when applied to an op-amp circuit of closed-loop gain of 100. I have searched all through my course material, online for ages and have only...
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    Calculating an single output from two inputs...maths help!

    No, the X values do change. Both the X and Z values will change when the arm only moves in one plane. Therefore: If the arm moves only in the X plane, this will alter the X and Z values. If the arm moves only in the Z plane, this will alter the X and Z values. Example: The arm is at 20...
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    Calculating an single output from two inputs...maths help!

    Ok, it is quite hard for me to explain but I will try a bit more. Fundamentally my device operates in two planes, X and Z. Where X is left to right and Z is up and down. It pivots in both the X and Z planes from a single point, imagine holding the end of a pen in your fingers, with your fingers...
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    Calculating an single output from two inputs...maths help!

    Hi, I have an application where I am using two devices: 1) Absolute Encoder 2) Inclinometer What I am doing is measuring the angle of a device in a single plane. My device is a pivoting arm which can move left/right and up/down. However, due to the mechanical setup, when the arm moves left...
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    Graph/Error correcting - maths formula NOT homework

    I only did this to check my method for the first section. Reason being is that my answers come out widely inaccurate. For example: When X is 20: 5th degree = 2951.85... 4th degree = 7298.71... 3rd degree = 5895.31... 2nd degree = 1604.61... 1st degree = 258.14... + 99.97... Brings my Y out...
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    Graph/Error correcting - maths formula NOT homework

    Sorry, I meant ^5 not ^2. Typo! :mad: So looking at the 5th degree: If my input value (x) was 10 for example, it would be (0.00092245...) x (10^5) = 92.25 Thanks
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    Graph/Error correcting - maths formula NOT homework

    Thanks - when I try and use the polynomial, the graph looks good but when I try and calculate off of the equation I get a very strange output. Would I be correct, that the element of the equation for the 5th degree is: If my input value (x) was 10 for example, it would be (0.00092245...) x...
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    Graph/Error correcting - maths formula NOT homework

    Hi, I hope this is in the right part of the forum. I'm working on a problem at the moment where I am measuring an angle across 180 degrees using an inclinometer, however for my application I consider this -90 to 0 to +90. From working out the mechanical position of my inclinometer, I am going...
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