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Suppose we have a sine signal applied to a inductive load. Is the inductance of the load changed if the frequency of the signal is changed?
In monostable multivibrators we use a trigger signal applied to the base of the transistor which is usually off to enter the astable region Can we instead have a pin which is connected directly ...
Is it possible to drive a PMSM motor - here I am referring to an AC motor with permanent magnets(stator wounded, rotor with PM) - in a way that there is no externally mounted rotor position sensor(...
Assuming we have a voltage regulator : Why do we have to ground Vin and Vout using 2 capacitors just like that?Co could be to provide a low resistance path to GND at high frequencies but what is...
Hello everyone, I have a simple circuit in which I control some LEDs via an MCU and DMG2302UK ( N-channel MOSFET ) The EN pin is connected to an MCU gpio pin that works at 3.3V. The circuit wo...
In this datasheet it says that the minimum resolution is 0.1uA for the 10mA range.What is this minimum resolution?Is it the sensitivity of the multimeter for the 10mA range?
I saw that equation of reactance is written like this $$I=\frac{V}{|R+X_L j|}$$ $$I=\frac{V}{|R-X_c j|}$$ When there's capacitor and inductor in a single circuit then it is written like : $$I=\...
I've seen a few different circuits (a) (b) (c) (d) described as "an O-ring circuit" or "an optimal O-ring circuit". What does the "O" and the "ring" refer to in such circuits? How do "O-ring circ...
If we have the transfer function of a LC high pass filter: $H(s) = \frac{sL}{sL+\frac{1}{sC}}$ If we want to find the pole of that filter in the end we get: $s = \frac{j}{\sqrt{LC}}$ and for a ...
I am trying to find the AC analysis of a BJT Hartley oscillator but I cannot continue. How do I find the voltage gain? When no feedback is there, we just find the output resistance and the current...
I have been trying to model this oscillator I was wondering if we can somehow predict the frequency of the oscillations.For small currents inside a diode from the Shockley diode equation $$ e^{x...
I am studying for a test in control systems and we have a practical part which is to program a analog computer. Here is a picture of the analog computer: The variable resistor is basically a vo...
This picture describes the behaviour of a single phase transform under resistive,inductive and capacitive loads(from left to right) How what exactly is $V_{1}$ ?Is it the voltage at the primary ...
I have been reading about thermal noise in resistors and I have a question: Suppose we have this circuit: Is C2 here to protect the voltage source from thermal noise?
I have a MOT that is rated 220V-50Hz only and i need to know its maximum operating power i tried to google the reference number but unable to find anything about its power, so how to figure out the...
Why can the channel capacity C of the additive white gaussion noise (AWGN) channel be denoted in different ways and how do they relate to each other? Examples: C = (1/2) * log2(1 + SNR) [bit?] ...
I have a HANTEK 6022BE oscilloscope and I'm monitoring three signals with it: FS (Frame sync clock). Pulse. Transfer complete. I'm using two channels of the scope to monitor a pair of these...
Hello,I want to simulate a delayed pulse going from 74ABT04 to the load which is UCC5304 where load with 400K i think. but my pulse source 74ABT04 is not an idial voltage source as shown in the s...
I’d like to create a stable IR LED light source. I’ve read that LED efficiency changes with temperature. I’ve seen two designs which used feedback through light to correct the LED temperature dri...
I would like to convert 5V rail I have on PCB to ±12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirem...
I got a vintage ('64) hifi sideboard for Christmas! It's super awesome. However, I don't understand the grounding. It has two female inputs on the backside that are labeled as "Grounding". There w...
How to find the equation of voltage of the top common node of R1,L1 and C1 after the switch is moved?
I recall vividly a story told by my grandfather who worked with high voltage power lines. A worker drove heavy machinery into 700kV line and then jumped out of the truck, instantly combusting upon ...
In the past, a large number of new active building blocks have been proposed and published by many researchers all over the world. In most cases, these new building blocks were used for realizing n...
I have a question about this circuit:(critically damped oscillation) For a critically damped oscillation for a series RLC circuit the equation of current has this form I(t)=D1te^(-at)+D2e^(-at) ...
How to find the equation of current of the RLC circuit after the switch is moved?
Assume a app generates a message (stack on computer).Each layer of the sending entity will put then control information in the data depending on the protocol and transmit the data to the next lowe...
Suppose we have this graph: How can we find the operating point (Q)?In common emitter collector we just draw a line from the vertical axis (Ic) at the point (0,VCC/RC) to the horizontal axis a...
I have here an acre-counter or crop counter device like the lykketronic shown below, using two AA batteries. It arrived without working. Upon opening its case, I found that the PCB is missing tw...
I was analyzing the design a hazard warning light.The spec of the light turn on off is given below. The flashing-light frequency shall be 90+/-30 times per minute. May I know in this case the...
Hello,i need to drive 5 mosfets as shown below. Each mosfet draws 15A when the pulse opens the mosfet. My power supply is gives the 48V but only 3.3A,If I understand correctly I need to put very...
Hello, I want to understand the math of the phenomena of capacitor as temporarary means of increasing the current supply. First I have created a current limited voltage source which give me 45V a...
May I know how to calculate a signals rise time from it's frequency. I found this article for the same. The formula given is Tr = 1/f*π. May I know is this applicable for PWM also.
I am currently learning amplifier design, after constructing the unity gain amplifier(which is a differential-input single-ended-output amplifier) in the unity-gain feedback configuration I have pe...
I want 3 SMPS (AC-DC) : Vout/Iout - 5V/20A , 12V/75A , 24V/30A Vin (AC) ~ 220V/50Hz I want it such that I can use Hard & Soft Kill Switches for turning off. Can you help me with the same. I tho...
Currently, I enrolled myself in a master's course this fall in the field of Computer Engineering. I am excited to create my microcontroller projects. I want to understand how much complexity is exp...
Hi guys, Can anyone help me please replace the NE555 IC in this circuit by MIC1555. I need to modify also the Voltage to 18v thank you. MIC1555 datasheet NE555 datasheet Edit: The circuit a...
I'm designing a PCB for a project. 12 volt input power supply is provided externally, so the user will buy a power adapter, so putting a popular DC jack on the PCB is the best choice.
Suppose we have this stream of data.Let's assume the data stream lasts 1 sec. How do we find the bandwidth of the data?Do we Fourier transform the signal in order to find its components in the ...
In a previous question we found that for a critically damped oscillation: $$ I(t) = 2 t e^{-0.5 t} $$But if we integrate to find the voltage through the capacitor: $$ V_{CO} + \frac{1}{C} \cd...
What is a typical value for capacitance of a real inductor? Does this internal capacitance exist only under AC and not DC?
I recently started working at a construction office in another country. I usually listen to music when working, and I saw a headphone jack in the wall, so I thought it is radio or something, I plug...
I was studying the Re model of a transistor: But the Re model for 2 different configurations (common emitter and common base )turns out to be the same! I don't know why I am really confused.How...
I am designing a low-pass filter with cut-off frequency = 100Hz and after the cutoff frequency from -3dB to -10dB the average decrease in db/Hz = -0.1 db/Hz.I know how to design a low-pass filter ...
Suppose we have a RC low pass filter of 1st order. If we add multiple stages every time we add a RC stage identical to our original does the slope of the curve in the bode plot db/Hz becomes wild...
The small signal analysis of a BJT when the BJT is in amplification mode: is easy.However what happens when the BJT is in saturation mode? Can we replace the dependent current source with a r...
Mini-circuits LNA PHA-LN13+ has suggested: Eval board Layout Eval Gerber The image took from the Gerber file (3rd ref.) (Though all 3-reference mentioned containing it): There I have som...
I've tryed to implement a local ground concept told by Olin Latrop here : He have told: (What I've perceived)You should not connect every gnd point instantly to gnd plane, since it can inject HF ...
The output collector-emitter part of a transistor can be thought of as a 2-terminal SPST switch controlled by the input base-emitter voltage or base current. So this transistor switch can control o...
Im designing a Hartley oscillator this time with a opamp providing the open-loop gain.I have tried drawing the small-signal analysis of my circuit to use KVL and KCL to find the conditions of opera...
