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LC High Pass Filter Equation:
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An LC high pass filter is an electronic circuit that allows signals with a frequency higher than a certain cutoff frequency to pass through while attenuating signals with lower frequencies. It consists of an inductor (L) and capacitor (C) arranged in a specific configuration.
The calculator uses the LC high pass filter equation:
Where:
Explanation: The cutoff frequency is inversely proportional to the square root of the product of inductance and capacitance.
Details: The cutoff frequency determines the point at which the filter begins to attenuate signals. It's a crucial parameter in filter design for applications like audio processing, radio communications, and signal conditioning.
Tips: Enter inductance in Henrys and capacitance in Farads. Both values must be positive numbers. For practical circuits, typical values might be in millihenries (mH) and microfarads (μF).
Q1: What's the difference between high pass and low pass filters?
A: High pass filters allow frequencies above the cutoff to pass, while low pass filters allow frequencies below the cutoff to pass.
Q2: How does component tolerance affect the cutoff frequency?
A: Component tolerances can significantly affect the actual cutoff frequency, especially since the calculation depends on the square root of the product of L and C.
Q3: What's the roll-off rate of an LC high pass filter?
A: A basic LC high pass filter has a roll-off rate of 12 dB per octave (or 40 dB per decade) above the cutoff frequency.
Q4: Can I use this for audio applications?
A: Yes, LC filters are used in audio applications, though active filters might be preferred for some applications due to size and cost considerations.
Q5: What happens at the cutoff frequency?
A: At the cutoff frequency, the output signal is attenuated to -3dB (about 70.7%) of the input signal level.