Questions tagged [filter]
A filter selectively processes input signals in frequency- or time-domain.
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How much power passes through the shunt component of a high-pass Pi or Tee filter?
I would like to send ~100W through an RF filter. Can you estimate the current passing through the shunt component without a circuit simulation assuming a reasonably high S21 value?
MLCC's are cheap, ...
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RC series circuit [closed]
I wanted to know what is the difference between these two circuits when they have the same output
I Need them as inpute for calculating an ADC
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What's the purpose of the band-pass filter in an RF transmitter?
What is the purpose of the marked band-pass filter?
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Relation between signal mixer and filters
Mixer output shown as red wave:
Can a band-pass filter be used to remove the low frequency shown as a blue sine wave and leave the rest high frequency just like the frequency shown as a green sine ...
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Do active filters exist that don't cause a voltage drop?
Pretty much all filters I have come across always cause some sort of voltage drop. A passive example is the classic RC filter, an active example is the capacitance multiplier (which is basically just ...
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Implementing an IIR filter for FPGAs [closed]
I need to implement an IIR filter in a Xilinx FPGA (preferably Verilog). I noted that there is an FIR compiler for FIR filters but no similar IP for IIR filters. So what is the most fast and efficient ...
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What all circuits can be considered as LC ladder filter?
I'm new to filter design. I read that the sensitivity of lc ladder circuits to component variation is less. The IEEE paper titled "Class-J SiGe X-Band Power Amplifier Using a
Ladder Filter-Based ...
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replace attenuators in filters with changing gain of each filters?
I have multiple filters that are all the same gain that are all attenuated differently with the same attenuator circuit. Is it possible to replace the attenuators with just changing the gain of each ...
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Do active filters count as amplifers?
Can we consider active filters to be amplifers?
If we use the folowing active filter design, and adjust R1 and R2 correctly that the gain is set to 10 for example, does the output signal comes out ...
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What is this component in a power supply?
We bought a Cisco 6500 series 6 kW PSU and took it apart. This is a module connected immediately to the inputs of the power supply unit. Does anyone know what it does?
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Pi Filter Design
I'm new to design, all the help is appreciated.
I'm drawing VCC12V from a external board for this application. I'm facing issues of EMI/EMC and voltage level of VCC5V is not that stable as expected to ...
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2nd order Butterworth Low-pass Filter [duplicate]
I updated my old filter with this, shown in the picture but I am not so sure it is correct. I guess the graph should have look like more low-pass filters graphs. The values and the circuit elements ...
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OpAmp filter drive capabilities
My application requires a high input impedance. Therefore I am using 2 x TLV313 OpAmps as unity-gain buffers for my ADS1296. They also provide an adequate common-mode output voltage (2.5 V) for my ADC....
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Designing 2nd order Butterworth low pass filter [closed]
I designed a 2nd order Butterworth low-pass filter, but it did not work correctly. What is the mistake in this filter?
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Op Amp diminishing rather than amplifying, but only inside the cutoff frequency of the filter it follows
I have a 7 stage passive Chebyshev filter designed to attenuate signals outside of a ~1MHz bandwidth centered around 50MHz in order to protect a clock input from frequencies that are too high or low. ...
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How to calculate cut-off frequency of an RC High Pass filter with two resistors?
Please consider the attached circuit. How would I calculate the cut-off frequency here? Should I treat resistors as attached in parallel? This is an actual circuit of an existing device, I cannot ...
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AD9361: how to compute datarate and configure filters
I will use AD9361 as a transmitter of a modulated baseband signal. The modulated baseband signal is implemented in FPGA/SDK.
AD9361 has real-time bandwidth of 56MHz but we have maximum 61.44 MSPS data ...
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Finding the frequency of a RC network pole given the relative gain at a frequency
In the Texas Instruments application note "Single-Supply, Electret Microphone Pre-Amplifier
Reference Design", the following circuit is discussed in section 2.1:
simulate this circuit &...
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Are T-parameters the same thing as ABCD parameters?
S-parameters can be converted to either T-parameters or ABCD-parameters, and both are considered a "transfer matrix". The conversion from S-parameters to T- or ABCD-parameters are defined ...
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Can admittance (Y) be used to calculate reactance when L and C values are calculated from the Y12 and Y11 parameters like normal as X=XL-XC?
My original question sought to understand the relationship between S-parameters and reactance. In the process of trying to figure that out, this second question arose. The actual question is at the ...
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Hardware debounce using RC filter and correct GPIO configuration on MCU side
I need a quick way of adding some de-bouncing to a button in hardware. I am aware that ultimately the software should really do it, but for now I came up with this, saw it somewhere on internet:
Does ...
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Second order active high pass filter
I am trying to design an active filter, which I assume is an active high pass filter according to what I see from the Bode plot.
I can get the transfer function from this plot and then I need to ...
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Second order low pass filter: two 1st order filters not-immediately cascaded
A second order low pass filter (LPF) can be made by cascading two active LPF (an RC network + opamp.) What happens if, instead of immediately cascaded, an active LPF acts at the input (buffer) of a ...
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How are S-Parameters and Reactance related, can one be calculated from the other?
I know that, for example, \$X_L=2\pi f L\$ will calculate reactance of an ideal inductor, but can this be calculated for a real component model? Given the S-Parameter values at some frequency from an ...
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How is this possible: Crystal filters for FM signals?
I am trying to make my own superhet reciever. I have achieved downconversion and I am trying to build a crystal filter that will only allow the crystal's resonant frequency through. In doing so, I had ...
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Confusion In RC circuit
I want to calculate voltage across the resistor.
I divided the circuit into two parts:
Charging=0<t<1, 2<t<3, 5<t<6(ms)...
Discharging=1<t<2,4<t<5,7<t<8(ms)...
$$...
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Microstrip on FPC board
Do anyone know, what is the strange track on FPC board on image below?
My guess is, it is something like a microstrip track.
The image is for a FPC board, that measure cell voltage of batteries.
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Power supply overload protection work around
I have the following power supply here
I need to switch on a contactor that uses around 3.2A inrush current for around 20ms (I cannot find the datasheet for this).
Now the power supply breaks down the ...
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Electret microphone to speaker noise
I have been working on a circuit where part of the work involves an electret microphone that gets the input signal and outputs it through a speaker. It happens to have noise emanating from the speaker....
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Passive equalizer design
I have circuit feeded from a 3.5 mm jack through a JFET common-drain buffer then i need the filter this audio input to pass bandwith 400-19600 Hz. I can do this with RC bandpass filter but then I need ...
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Can you cascade simple wideband bandpass active filters?
Can you cascade this type of active bandpass filter?. The bandpass filter type in the picture below seems to be the simplest type of an active bandpass filter. I am wondering if they can be cascaded ...
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Making a voltage range filter (or a voltage bandpass filter)
I have been trying to hack together a voltage range filter that will pass voltage to a load only when the input voltage is between 1-2V. My input source can range from 0-3V. (I don't want to scale the ...
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Bandpass filter doesn't work when implementing PCB
I have been trying to make a 5th-order Chebyshev filter going from 500 MHz - 570 MHz and a 3rd-order Chebyshev filter going from 500 MHz - 540 MHz. This is my first time making a filter into a PCB.
No ...
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Help Understanding Opamp Topology (Infinite Gain Multiple feedback with Resistor to Gnd?)
I ran across the following band-pass circuit and I'm not entirely sure what R14 is doing here. The following is a screenshot:
For some context, the supply is a ...
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Which of the following is LC lossless function?
Which of the following is LC lossless function and why? Pick one of the valid LC lossless functions and realize it using Foster-I and Cauer-I form.
I have been trying to solve this question for ...
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Digital Signal Processing vs. Analog Signal Processing for 100kHz DAQ project
I have a dumb question to ask (for a lot of you) but it has been bugging me for a while and I need someone who can give me a clear answer... (I'm a second-year in electrical engineering)
So, I am ...
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RC filters in JFET negative feedback
I saw a useful answer about JEFT negative feedback here and so I thought I'd ask for some help too!!
I'm attempting to create a JFET gain stage that uses a filter in a negative feedback loop to boost ...
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Confusion with determining lossless function
Why is not a valid lossless function?
Below condition 1, 2, 7 or 8 constitute the sufficient conditions for being a lossless function, but I am confused why is this not a valid lossless function. ...
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Receiver circuit design testing
I am trying to make a receiver circuit that is able to receive an LED input (further down the line receiver input from a laser).
Firstly, I am trying to test the photodiode that will be used. I am ...
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Sanity check on this DAC reconstruction filter design
I've altered a reconstruction filter circuit to use the LTC728XT instead of the AD8608 op-amp used in the example circuit below. Is anyone able to see any issues with my attempt? This is being used as ...
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Spark plug noise on power supply
I am working on a motorcycle diagnostic tool. Everything works fine except for the fact that when the engine is turned on, in some motorcycles spikes start appearing all over the circuit, and the ...
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Filter signal on oscilloscope using math functions
Is there a way to do a time domain low pass filter, in software, on a Siglent SDS2000X Plus series oscilloscope using these math functions?
The ones that stand out the most are ...
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Best way to decompose addition of waveforms?
I am searching for a way to decompose the exact components of additions of known waveforms.
For example, lets say there is a waveform that is sum of multiple sinc functions.
The sinc function's ...
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Bandpass filter test results not same as simulated results
I am designing a 40 kHz bandpass filter for a university project involving a portable ultrasonic device.
I have designed a 40 kHz filter using the Linear Technology Filter Design Tool with a single ...
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Keep "in voltage" stable of switching regulator
I powered a Raspberry Pi pico (RP) from the Atari Joystick port of a Sega Master System (SMS) (it should be able to supply 5 V and max 100 mA).
RP using RT6150B buck-boost like this (+5 V from ...
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Transfer function for Sallen-Key notch filter
How can I find the transfer function H(s) of the following circuit by using impedance of the circuit?
Should I instead do it by nodal analysis?
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Band pass filter with single-supply op-amp not filtering
I am working on a university project that requires me to build a 40kHz band pass filter for receiving an ultrasonic signal.
The filter is to be implemented into a portable device powered by a 9V PP3 ...
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Multiple Feedback Band Pass Filter Noise
I designed a multiple feedback filter using the analogue devices filter wizard. I have never designed this type of filter therefore I followed up by reading about it and manually calculating the ...
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LC filter for inverter
I am designing a 1500W inverter. With 24VDC input source and 220VAC 60Hz output voltage.
I currently have the topology shown in circuit 1. This results in a square wave at 60Hz. But I need the output ...
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My Chebyshev filter band pass filter produce tiny values
I am using a Chebyshev band pass filter:
Fs = 50
wc =[0.1,0.9]
Ap = 0.025
filter_order=2
z, p = signal.cheby1(filter_order,Ap, wc, 'bandpass',analog=True)
The ...
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