# ppCap(area, thickness, Er)

Calculates Parallel Plate Capacitance

### Syntax

o_ppCap(a,b)
  area: scalar Real - area in mm^2
  thickness: scalar Real - thickness in mm
  Er: scalar Real - relative dielectric constant (unitless)
  return: Real - capacitance in Farads

### Usage

Given an area and thickness plus the dielectric constant, basic physics provides the equivalent DC capacitance for two parallel conductors separated by a fixed amount.

### Location

menu: veeos ==> Engineering Calculations ==> ppCap

library: eeLib

### Example

A 1mm square pad on 10 mil high density alumina has an equivalent capacitance of o_ppCap(1, 0.25, 9.9) = 0.35 pF

### Notes

This function calculates C given the formula C=EoErA/d, which determines the classic DC parallel plate capacitance without taking into account any fringing effects. For capacitors whose electrical aspect ratio is small (very wide compared to thickness) this is a good approximation since fringing is minimal. For other capacitors one should start looking at EM techniques for a better answer.

### Reference

- One source is GSU Physics Department, although any beginning electrical field text will have this also.

### Supported On

VEE 7.0+, All platforms.

### See Also

© 2015-2021. All Rights Reserved. Stan Bischof (stan@worldbadminton.com). Last updated 09 August 2021 18:24.