Interdigital capacitor calculator

Interdigital capacitor calculator calculator can be used to calculate the capacitance of an interdigital capacitor based on its physical parameters.

Input Parameters

Calculation Results

Calculation Formula

Capacitance (C) = (ε * N * w) / (π * ln((8d/w) + 1))

Where:
C = Capacitance (F)
ε = Dielectric constant
N = Number of fingers
w = Finger width (μm)
d = Gap distance (μm)

Interdigital capacitor calculator Calculator Usage Guide

Learn how to use the Interdigital capacitor calculator calculator and its working principles

How to Use the Calculator

  1. Enter the gap distance (d) in micrometers (μm).
  2. Enter the finger width (w) in micrometers (μm).
  3. Enter the dielectric constant (ε) of the material between the fingers. For vacuum, it is approximately 8.854 × 10-12 F/m.
  4. Enter the number of fingers (N) in the capacitor.
  5. Click the "Calculate" button to compute the capacitance.
  6. The result will be displayed in farads (F) in scientific notation.

Working Principle

An interdigital capacitor consists of two parallel plates with interleaved fingers. The capacitance of such a capacitor depends on the gap distance between the fingers, the width of the fingers, the dielectric constant of the material between the fingers, and the number of fingers.

The formula used to calculate the capacitance is derived from the parallel plate capacitor model and takes into account the geometry of the interdigital structure.

Applications

Interdigital capacitors are used in various applications, including:

  • RF and microwave circuits
  • Filter design
  • Capacitive sensors
  • Integrated circuits