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    Electrical circuit Analysis

    I am trying to understand the below circuit My analysis of the circuit is since 5V is connected to both ends of the circuit there will be no current flow. Is it correct? Anything more i can understand from this circuit, this circuit is created by me to analyze different ways.
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    Power Calculation

    Consider a simple switched circuit VDD = 600V RL = 100 Ohm. The on-state resistance of the switch, Ron = 2Ohms. What is the magnitude of the power in kW, provided by the source when the switch is closed? Power = V^2/R = 600 * 600 / 102 =3.52kW. The calculations are ok?
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    Opamp Filter circuit

    Another Opamp filter circuit, this is the recommended filter circuit from ST micro ST datasheet on page 13. I tried to simulate the circuit using Ltspice but i do not see any gain I have not yet verified the filtering. But why there is no gain?
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    Noise and Glitches

    I am struggling to understand and fix the issues of noise and glitches, it is motor controller application with frequency switching of 20KHz, what is the impact of this kind of pwm switching. What exactly happens in this kind of application, does it impact PCB, signals everything? How do i know...
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    Opamp + capacitor gain circuit

    Trying the impact of capacitor in the opamp circuit as below The equations of the opamp are V1 - i1R2 -i1R1=Vout -> 1 The voltage at inverting input is same as non inverting input V1 - i1R2 = 1/Cic dt -> 2 But there is no current in positive terminal as high impedance of the opamp, so i assume...
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    Inductance circuit

    I want to simulate a condition and verify the current behavior in Inductor. The below is the circuit The response of the circuit is I want to simulate a case where my input is off pulse goes to 0V, then the current shall flow for certain time in the same direction. I think that is the nature...
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    Oscilloscope always showing Sine Wave

    I have a real problem with my scope for any signal i connect it only shows sine wave, even if i connect with some DC source of 12V it only shows sine wave, not sure why. I tried all the methods but of no use.
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    Opamp circuit clarifications

    I am trying to solve the opamp circuit as below (V2 - Vopamp)/1.5e3 + (3.3 - Vopamp)/22e3 = Vopamp / 2.2e3 + C1 * dVopamp/dt ->1 V2 - pulsed input C1 - 14e-9 F 0.66*(V2 - Vopamp) + 0.045*(3.3 - Vopamp) = 0.45*Vopamp + 14e-6*dVopamp/dt ->2 0.66V2 - 1.155Vopamp + 0.1485 = (14e-6)dVopamp/dt...
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    Basic Circuit Analysis

    I am trying to solve the basic circuit but struggling to get the result. I get 0.33A and 2.33A but the result from simulation is I1 = 1.33A I2 = -0.66A. What is missing?
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    Digital Input output observing rise and fall time

    I am toggling a port but i observe a rise and fall time in digital output the micro used is ST and it is custom board. How do i rectify the issue? The switching is done at every 10KHz. Does it mean the PCB is not proper and has high capacitance?
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    LR circuit for PWM Input

    If i give a pwm signal for the LR circuit with 50% duty cycle, during on the ON time the current will increase and during the OFF time does the current decreases and reverses its direction during the OFF period or it only decreases. My question is mainly on why the current does not reverse?
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    Back Emf Waveforms

    This is the back emf waveform from motor data sheet I can understand the back emf as A, B and C. But what does C+ A-, A+ B-, B+ C- mean?
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    Flow of Phase currents

    I am really confused with phase currents direction of flow, please help to understand i am referring to the below link phase current flow and referring to the diagram and i am using the 3 shunt topology, my main question is if you are using the FOC and SVPWM used we will be imposing the sine...
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    Phase current calculation

    I have seen a 24V PMSM motor specifications and it shows the line - line resistance of 0.57 ohm and L-L inductance of 0.64, suppose i apply an algorithm (sinusoidal etc) and a voltage of 11V RMS at the inverter side, the current that would be flowing is 11/0.57 = 19.29 Amps. It is a small motor...
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    Inverter Leg Current Sensing

    Please clarify me on the below doubts There are 3 methods of current sensing 1. Inline current sensing 2. Inverter leg current sensing 3. DC Bus current sensing In the Inverter leg current sensing suppose i sample the currents at every 50us for FOC (field oriented control) the currents will...
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    PWM with 50% duty cycle

    I keep getting questions on how inverter works for different duty cycles. Suppose the inverter has 3 half bridges with 6 switches. If i apply 50% duty with center aligned mode. Then 50% of time in 20KHz the upper switches will be ON and 50% of the time the lower switches and the net result is 0...
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    Power Isolation

    I have the following board As shown the board is a single board with some part for microcontroller powered by 5V, there 3 ICs for gate driver which are powered using 12V supply. It works well as long as i do not switch on PWM, but once PWM is on a huge current is drawn from 5V supply and micro...
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    Hardware issues

    I am basically a firmware engineer but presently i have an emergency where i need to debug the hardware issues. 1. I am seeing several micro controller failures, i reached this conclusion as i could not flash the microcontroller. I wanted to know if i probe the micro controller pins using the...
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    Testing of currents

    I planned to test the phase currents i have board which is partially populated, need to confirm if the firmware is reading the currents properly The Red section is a microcontroller and has in built Opamp which will amplify the signal and then connect to ADC (internal to micro). I created the...
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    Linear Regulator Clarifications

    I want to convert from 5V to 3.3V using LT1117-3.3 IC, the data sheet is Linear Regulator. I have attached the LT spice model, few questions are, do i need to use resistor or not at the output side, i get 3.3V output in all cases. In the data sheet resistors are used. Please advise.
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