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Tagged with low-pass or low-pass-filter
667 questions
0 votes
1 answer
114 views
Malfunctioning Low Pass LC Filter at Class D Amplifier Output
I have an LC filter at the output of my class d amplifier. It uses a 47uH inductor and 1.5uF capacitor with a 4700uF ac coupling capacitor and fuse connected to the input of my speaker.This is the ...
- 75
0 votes
2 answers
107 views
Review my 5-37Hz filter and amplifer. Will it work? Am I missing any other simulation. (Made in LTspice)
Context. I am using this filter and amplifier to detect Schumann resonances. These are EM modes of very low frequency (7,14,20,28,33) of pT range. My goal is to use a copper coil sensor. These are AC ...
- 49
0 votes
3 answers
240 views
Op-amp biasing not working as intended
This is regarding the biasing of a second order Sallen-Key low pass filter. The filter seems to work fine when I use a sinusoidal input in LTSpice and produces an output centered around 1.65 V. ...
- 11
0 votes
5 answers
149 views
Can I use OPA2227 to Make Low Pass Filter and Amplifier with Gain of 50~100
I am looking for low noise opamps and the one that caught my eye was OPA2227 and is available locally. Its a dual opamp and was wondering to use it for the as low pass filter with cutoff of 38 Hz and ...
- 49
1 vote
1 answer
95 views
Why does a T-filter simulation cut off frequency differ significantly from calculation?
I’m replicating a circuit design of a T-filter to filter out noise in a 12 V power line rail to try an test and measure the T filter's bandwidth from its cut off frequency. The filter components are: ...
- 411
0 votes
3 answers
118 views
How can I bias this low pass op amp filter circuit?
How can I provide a DC bias to my low pass op-amp filter? I would like the input signal to be centred around 1.65V. My first idea was to use a 3.3V supply, use a voltage divider and then tap off from ...
- 11
-2 votes
0 answers
58 views
Filter Design on Cadence AWR
I have been trying to implement an order 5 Chebyshev LPF by using Kuroda's identity and Richard transformations to convert the standard circuit to microstrip lines and open stubs. This is the design I ...
- 1
1 vote
0 answers
53 views
RC filter for a fast delayed ramp
Consider simple RC networks with 3 external terminals (GND, IN, and OUT) and, at most, 4 total components. To be clear, each component is either a resistor or a capacitor. For a 1V voltage step on IN, ...
- 916
4 votes
2 answers
452 views
Low pass filter output stuck at supply voltage
The schematic shows 2 transimpedance amplifier circuits on the first stage, for reference and sample photodiodes. The outputs are then connected to sallen-key butterworth circuits for low pass ...
- 41
6 votes
4 answers
700 views
Amplifying signal post low pass filter
I’ve designed an elliptic low pass filter with a very steep roll-off around 18–20 MHz. The filter’s response is close to what I need, and the cutoff behavior is critical, so my goal is simply to shift ...
- 99
1 vote
1 answer
168 views
Should I add an RC filter to the analog input pin (STM32F103 ADC) for a triac light dimmer application?
I'm designing a custom PCB using an STM32F103 microcontroller to control a triac-based light dimmer. The firing angle for the triac is determined by reading the voltage from the potentiometer. The ...
0 votes
1 answer
135 views
Proteus won't simulate my RC circuits (low-pass and high-pass filters)
I have a bigger project where I need this two signals, a ramp and a pulse. Basically, one that starts at 0V and goes up to approximately 5V and stays there, and another one that does the opposite (...
7 votes
4 answers
1k views
Low Pass Filter not having expected response
Trying to build a chebyshev low-pass RF filter to attenuate anything above 24MHz, however am not able to get a continuous drop-off in the pass band. It goes down to -20 dB and then just flattens out. ...
- 181
5 votes
1 answer
376 views
Why the 5kHz low-pass filter is not working in my simulations in LTSpice?
The circuit I'm trying to simulate is shown in Figure 1 below. SOURCE: Tools for physiology labs: an inexpensive high-performance amplifier and electrode for extracellular recording. Land BR, ...
0 votes
0 answers
49 views
Unexpected noise in cell voltage readings from AFE with sigma-delta ADC – RC filter cutoff frequency or resistor drift?
I'm working on a battery management system for an EV motorcycle. My setup includes an AFE (BQ769x2) with an internal sigma-delta ADC for voltage sensing. Each cell voltage input has a dedicated RC low-...
- 67