Free online calculator
LC resonance calculator

Example Resonant frequency: 5.033 kHz
At that frequency the two reactances are equal — — and the branch currents cancel, so this parallel tank presents its highest impedance.
What you enter
- L
- C
Free online calculator

Example Resonant frequency: 5.033 kHz
At that frequency the two reactances are equal — — and the branch currents cancel, so this parallel tank presents its highest impedance.
What you enter
LC tank energyEnergy sloshing between coil and capacitor while R taxes it away.
NE555 timerFully wired timing network — pins are grouped by function, not physical DIP order (see the 555 timer entry in Pinouts for the real pin layout). RST is…
RC filter— the −3 dB point, where the output has fallen to 70.7 % of the input. R in series, C to ground: C’s impedance falls as frequency rises, increasingly…
Reactance (capacitive / inductive)Capacitive: — reactance falls as frequency rises, so a capacitor passes high frequencies.
Sallen-Key filterA unity-gain second-order low-pass: sets where it turns, sets the shape. Q is peaking, not frequency — 0.707 is flat to the corner, below that the…
Time constantRC: — RL: — one time constant is how long the circuit takes to cover 63.2 % of the remaining gap to its final value.
LED series resistorNobody wires just one LED. Each string is its own series chain of LEDs behind its own resistor — stringing more LEDs raises the headroom the resistor has…
MOSFET gate driveA MOSFET draws no steady gate current, so holding it on is free — but every edge has to shovel the whole gate charge in and back out again, and is real…
NTC thermistorBeta-model resistance of an NTC at any temperature (T in kelvin), plus the divider voltage an ADC would read.