Skip to main content

Questions tagged [filter]

A filter selectively processes input signals in frequency- or time-domain.

Filter by
Sorted by
Tagged with
1 vote
3 answers
73 views

Filter on SEPIC architecture output for making +/- 60 V from 11 V input

I'm working on a LM5155 Boost/Flyback/SEPIC controller reference design PMP40488 from TI. The goal of the design is making variable output (maximum +/- 60 V) from 11 V input. My question is related to ...
Andromeda's user avatar
  • 511
0 votes
2 answers
53 views

Active Bandpass with "Tunable" F Using Potentiometer

I'm trying to construct a simple bandpass filter circuit using the multiple feedback topology with one op-amp (I'd like to leave out a dual-opamp approach for now). I'd like the center frequency to be ...
Nils L's user avatar
  • 103
0 votes
2 answers
51 views

capacitive filtering of power line transients without power loss

I've been researching so-called "surge capacitors", which are claimed to augment surge protection devices (SPDs). The claim is that SPDs usually have at least a 5-10 ns response time, and ...
Special Sauce's user avatar
0 votes
1 answer
46 views

Second order low pass filter cut off frequency calculation

I found this circuit which filters an incoming pwm pulse train from a Delta-Sigma ADC to an analog value. The PWM pulse has an amplitude from 0 to 5 V and duty cycle varies from 10% to 88%. And the ...
AK47's user avatar
  • 99
0 votes
1 answer
64 views

Part name of this IC - "LLA#537"

I want to know the part numbers of the components marked as shown in the attached image.
Bang Duong's user avatar
4 votes
1 answer
188 views

Part name of this IC - Analog Devices, 8-pin, "S 6B" A 06" "C 42"

I want to know the part numbers of the components marked as shown in the attached image.
Bang Duong's user avatar
2 votes
1 answer
79 views

Pi-Filter Simulations Comparison

I am trying to simulate the filter impedances on LTspice. There are two images of the simulation results of the same pi-filter on LTspice and Redexpert. Although I am not sure the parameters are ...
mocal_381's user avatar
1 vote
2 answers
106 views

Why don't we use an integrator as the loop filter of a PLL?

In a book on phaselock that I was reading, it mentioned that ideally, one would use an ideal integrator as the loop filter of a PLL. Since we can implement integrators with op-amps, why don't we use ...
Arthur Prudius's user avatar
0 votes
1 answer
90 views

Why is the filter capacitor (used to filter pulsing DC) overheating MOSFETs in a buck converter?

I am trying to create a microcontroller (Arduino) based DC to DC buck converter with CC and CV features. For now, I am using a 20 V 5 A input source. Output voltage (target voltage) is settable by the ...
irshukhan's user avatar
0 votes
1 answer
95 views

How to calculate a differential + common mode LPF circuit?

I'm trying to validate my understanding of a differential + common mode LPF circuit using the AK4499EX datasheet (019001308-E-00 2022/07 version, p. 47). It presents the following circuit: and its ...
Alexander Abakumov's user avatar
0 votes
0 answers
59 views

How do data acquisition systems work?

This is a theoretical question. All the signal processing electronic systems I have developed up to now have customized electronics to filter out unwanted noise. Because their electronic filters are ...
Iskander's user avatar
2 votes
1 answer
83 views

Filtering noise with low pass filters

If I have a signal that looks like v(t) in the image. The signal is a high frequency noise at frequency f1, that repeats with a a lower frequency of f2. If a low pass filter is applied that attenuates ...
AlfroJang80's user avatar
  • 3,145
0 votes
2 answers
71 views

Coupling LNA and Band-Pass Filter Properly

I am planning to use the BPF-A127+ band-pass filter with the GALI-74+ low-noise amplifier, which are from Mini-Circuits. The datasheets are provided below: BPF-A127+ Datasheet GALI-74+ Datasheet There ...
Karakoncolos's user avatar
-1 votes
1 answer
78 views

Butterworth Filter for SMPS

If the performance of a Butterworth filter is dependent on the load impedance how do high voltage high power 1kW+ SMPSs manage to achieve smooth output ~100mV peak to peak across wide ranges of load ...
beardeadclown's user avatar
0 votes
4 answers
134 views

Average filter of a signal in C

I'm having troubles designing a code for an ADC measurement, I'm trying to read a signal that comes from charging a battery with pulses, so the signal will be something like the photo uploaded. ...
samuel mattio's user avatar
0 votes
0 answers
54 views

3-band Equalizer circuit

Hello, I'm working on my pcb project-3 band equalizer. This is my circuit so far, it has 100Hz LPF, 1kHz BPF, and 4kHz HPF in parallel. While it works well by passing the frequencies I want when I ...
GL Park's user avatar
  • 31
-2 votes
1 answer
74 views

Equalizer circuit using low pass filter

I'm working on my circuit theory project. My goal is to make a simple 3-channel equalizer using 1 low pass filter and 2 band pass filter. Here is my circuit. Problem is, the 8kHz passive low pass ...
GL Park's user avatar
  • 31
1 vote
1 answer
48 views

What happens when the value of resistances used in a differential input filter for a current sense amplifier circuit is too small?

I am working on a current sense amplifier circuit with the following configuration: While the circuit works, the filter is not performing as intended. Specifically, it should act as a low-pass filter ...
Zhi's user avatar
  • 41
0 votes
2 answers
40 views

Rotary encoder filter schematic unclear

I have a PEC11R-4215F-S0024 rotary encoder and want to build a filter circuit but I do not understand which parts of the schematic are connected to their respective pins. Additionally I only see 4 ...
Sandvall's user avatar
0 votes
1 answer
51 views

Mutliple series inductors instead of single inductor

For the larger package size and slightly better SRF and Q I would prefer to use 3 series SMD inductors instead of the only 270 nH SMD I can find with the required Q. Also I would avoid winding my own ...
kellogs's user avatar
  • 1,061
0 votes
0 answers
55 views

Proof of ripple voltage of capacitor filter?

From Electronic Devices and Circuit Theory by Robert L. Boylestad: To get an equation for ripple voltage, the book wrote, $$\frac{V_{r(p-p)}}{T_1}=\frac{V_m}{\frac{T}{4}}$$ How did they come up with ...
Plague's user avatar
  • 1
0 votes
2 answers
55 views

Can the impedance of the source affect the response of a high-pass filter?

Having a simple RC high-pass filter, can a high signal impedance change the cutoff frequency response? Or more practically, should a resistor before the capacitor be included in the calculation for ...
boromyr's user avatar
  • 53
0 votes
1 answer
45 views

Ignoring current spikes

I have a circuit which measures a current draw going to System A, waits for it to rise from 0.24A to 0.26A, then has a 30s delay before supplying power to System B. If the current drops below the ...
InBedded16's user avatar
0 votes
2 answers
111 views

LC filter design

I'm trying to design a simple functioning LC filter. My input signal is a square wave with a maximum value of 230 V, a minimum value of -230 V, and a frequency of 50 Hz. I want to convert this to a ...
Serkan Kaya's user avatar
0 votes
2 answers
64 views

What happens if a low-pass filter and a high-pass filter are interchanged in a band-pass filter?

what happens in this circuit if I interchange the highpass filter and lowpass filter how does it affects the gain and phase shift
serkan's user avatar
  • 33
1 vote
1 answer
57 views

Common mode and differential mode filters order

In power supplies input filters the common mode block (typically a common mode choke) is usually placed first, and then the differential mode block follows. The image shows this structure. Is there ...
Isacco's user avatar
  • 89
3 votes
4 answers
1k views

Why is my band pass filter giving a gain of 0.5 in the -3 dB gain region?

I designed a band pass circuit but it gives me a gain of 0.5 in the band region. Shouldn't it be 0.707?
serkan's user avatar
  • 33
0 votes
1 answer
41 views

Setting 'H' in the Chebyshev approximation

For the Chebyshev approximation, \$ \frac{V_0}{V_{in}} = \frac {h}{D_n(s)} \$, and I was wondering how you actually set \$h\$. I know that \$h\$ is chosen to so that: \$ \frac{V_0}{V_{in}} = 1 \$ for \...
5eamus's user avatar
  • 5
1 vote
3 answers
86 views

Full wave bridge rectifier with Pi or T filter simulation won't converge

I'm designing a full wave bridge rectifier and want to compare a pi filter and T filter after the rectification. I intend to add a transformer at the input and a buck-boost converter on the output. ...
BTB18's user avatar
  • 13
0 votes
1 answer
50 views

How can I do inverse Laplace of this transfer function to get the step response of the RLC circuit?

I have found this to be my transfer function for the circuit. I have tried doing partial fraction decomposition, but I end up with an s on top which I don't understand what to do with.
Even's user avatar
  • 1
2 votes
1 answer
71 views

understanding the recommended impedance match for a SAW filter

I'm trying to understand the recommended impedance match for a TA0168A SAW filter input. The datasheet is https://www.rfmw.com/datasheets/taisaw/ta0168a%20_rev.2.0_.pdf In my first circuit I'm trying ...
TvE's user avatar
  • 286
0 votes
0 answers
49 views

Fan noise due to Harmonics while running on UPS?

When mains is not available, ceiling fan will run on UPS and create a different sound/noise. I know that it is due to harmonics. But how can we remove this noise? By getting a high quality inverter, ...
DSP_CS's user avatar
  • 1,219
0 votes
1 answer
161 views

Wideband Impedance Matching for Inductive Source/Load

I'm designing the frontend of a receiver and I want the output impedance to be 50Ω so that I can get as much power into the mixer. I tried placing a bandpass filter (image filter for 88-108MHz) in ...
TheButterMineCutter's user avatar
0 votes
1 answer
81 views

How to design a 2nd order low pass filter [closed]

I have a question about second order low pass filters. I have a DC/DC power supply at 3.3 V and I would like to filter this signal to address any disturbance from 50 Hz (ideally only keep the DC ...
MisterElec94's user avatar
3 votes
1 answer
266 views

Anti-aliasing filter for 3.3 V ADC at 1 MHz

I am designing an anti-aliasing LPF for a 16-channel ADC on a custom STM32F415-based board. This design will ultimately be put on a car and used as a DAQ. I am planning on running the ADC with a 30 ...
ABashara's user avatar
1 vote
2 answers
102 views

Filter design according to harmonics in an inverter

According to the Fourier series, when AC waves of different frequencies are added to the fundamental frequency, we can obtain waves such as square and sawtooth. When we filter out the harmonics in ...
Mhan's user avatar
  • 377
1 vote
2 answers
91 views

Avoiding upstream resonances with harmonic filters

I've got quite a few issues with harmonic currents on a VFD so I designed a (fat) harmonic filter. It's single phase so it's designed to block the third and the fifth harmonic (150Hz and 250Hz, here). ...
Lorenzo Marcantonio's user avatar
1 vote
2 answers
121 views

RC or RL high pass audio filter?

Some bass guitars from the 60s, namely Gibson and Guild, used RL, LC, or RLC high pass filters to reduce bass frequencies if desired. The control for these switches was commonly referred to as the &...
Scoid's user avatar
  • 13
0 votes
1 answer
53 views

Specific frequency filter

I want to use an insolation monitoring system that outputs different frequencies for every state. Exactly 0, 10, 20, 30, 40, 50 Hz but I want to use the 10 and 50Hz only. Is it possible to build a ...
NIKOLAOS PASCHALIDIS's user avatar
7 votes
5 answers
3k views

Do faster responding low-pass filters exist compared to a traditional RC filter?

Lets say you have a very short DC pulse that has some sinusoidal noise in it. But the duration of the pulse is very short...maybe 0.5 µs. For an RC lowpass filter to respond quickly enough to begin ...
BobaJFET's user avatar
  • 1,012
1 vote
1 answer
67 views

PI filter for two buck drivers for a low-emi solution

I'd like to save space on a circuit that uses two buck LED drivers. The circuit is designed for a low EMI solution and there are two separate PI filters on each Vin pin (recommanded on the datasheet). ...
msch's user avatar
  • 83
0 votes
0 answers
74 views

Determine the transfer function for the Butterworth bandpass filter? (At the Transfer Function Factoring and Sp Substitution stage)

The Parameter $$a_{pass} = - 1dB$$ $$a_{stop} = - 20dB$$ $$f_{pass1} = 10kHz$$ $$f_{pass2} = 30kHz$$ $$f_{stop1} = 5kHz$$ $$f_{stop2} = 60kHz$$ A. Approximate Low Pass Filter Filter Ordo $$n_B = 4.29$...
SKevinAR18's user avatar
1 vote
0 answers
47 views

How to read graphs for a simulated EMI filter

Hello everyone, I'm in the process of designing an EMI filter for a charger that is meant to connect to a trucks 12 V output. I've based the design of the filter off of the MAX17703 evaluation kit (...
Trynabal's user avatar
1 vote
0 answers
61 views

How to determine the transfer function of this pi filter?

I have this pi filter, I wonder how do i determine the dynamic model and the transfer function of this filter?
Kuuhaku's user avatar
  • 11
0 votes
1 answer
86 views

Why is there a shift in cutoff frequencies of filters, and how to fix it?

I am doing a project where I am designing my own EEG circuit. I aim to keep it fairly simple and essentially design my circuit to do two things: Amplification Filtering I want to design the circuit (...
Soumil Gupta's user avatar
2 votes
2 answers
85 views

Finding transfer function of high-pass circuit

I've already done the calculations myself, but I am getting a completely wrong answer for the poles and zeros. I'm not sure what I am doing wrong. If someone could point out my mistake please I would ...
MXVG's user avatar
  • 69
3 votes
2 answers
80 views

Current peak on a low EMI buck LED driver

I'm designing a buck LED driver using the LT8376 and I'm following the typical application for a low EMI solution (page 26). On the output, the schematic proposes a 100 nF capacitor in parallel with ...
msch's user avatar
  • 83
0 votes
2 answers
78 views

Understanding Legacy Hardware Filter

I'm working with a schematic of a legacy signal filtering hardware my company is using and was wondering if anyone can understand/explain what the sections of opamps are doing. I plan on modifying it ...
Aaron's user avatar
  • 3
0 votes
2 answers
128 views

Can I make an extremely sharp filter?

I am asked to design a circuit to measure certain signal in range of about 100 kHz, while interference that may appear can be about 150 kHz. Is it even possible to split the two? What needs to be done ...
TQQQ's user avatar
  • 1,357
0 votes
0 answers
48 views

Low noise high voltage gain amplifier

I have a very small voltage output in microvoltage range. I want to amplify it to atleast milivolt. So a voltage gain of 10^4 is required. Can anyone suggest any suitable amplifier for that?
Brishti's user avatar

1
2 3 4 5
50