Calcolatore Larghezza Pista PCB
Calcola la larghezza minima della pista del circuito stampato per la corrente richiesta.
Minimum (Nyquist) Rate
40.0 kHz
Minimum (Nyquist) Rate vs Maximum Signal Frequency
Formula
Nyquist-Shannon Sampling Theorem
Formula
f_sample >= 2 x f_max
The minimum sampling rate must be at least twice the highest signal frequency to avoid aliasing. In practice, sample at 2.5x or higher and use an anti-aliasing filter.
Esempio Risolto
Audio signal with 20 kHz maximum frequency, 2.5x oversampling.
- 01Nyquist rate = 2 x 20 = 40 kHz (minimum)
- 02Practical rate = 2.5 x 20 = 50 kHz
- 03Sample period = 1000 / 50 = 20 us
Domande Frequenti
What is aliasing?
When sampling below Nyquist rate, high frequencies fold back as false lower frequencies, corrupting the signal irreversibly.
Why oversample?
Real anti-aliasing filters cannot have infinite roll-off. Oversampling provides margin for the filter transition band.
Why is CD audio 44.1 kHz?
Human hearing extends to ~20 kHz. Nyquist requires 40 kHz minimum. The extra 4.1 kHz provides margin for the anti-aliasing filter.
Impara