Converters & Calculators
Use the below converter to convert mils to: mm, Oz, um, inch.
Type a value in a field to convert:
mm:mil:
Type a value in a field to convert:
mil:Oz:
Type a value in a field to convert:
um:mil:
Type a value in a field to convert:
inch:mil:
Use below to calculate any control impedance conductor (if you don't see it just refresh the page):
Use below calculator to calculate trace width , and via diameter according to requested current:
This Javascript web calculator calculates the resistance, voltage drop, and power loss of printed circuit board vias.
Inputs:
| Finished Hole Dia | ||
| Plating Thickness | ||
| Via Length |
Optional Inputs:
| Applied Current | Amps | |
| Plating Resistivity | Ohm-cm |
Electrical Results:
| Resistance | Ohms | |
| Voltage Drop | Volts | |
| Power Loss | Watts | |
| Estimated Ampacity | Amps |
Thermal Results:
| Thermal Resistance | Deg. C/Watt |
Notes:
Resistance = Resistivity*Length/Area
Area = pi*(Inner_dia + Plating_thk)*Plating_thk
Resistivity = 1.9E-6 Ohm-cm (plated copper)
(plated copper is much more resistive than pure copper)
Copper Thermal_Resistivity = 0.249 cm-K/W (at 300K)
Est_Ampacity [Amps] = k*(Temp_Rise [deg C])^b*(Area [mils^2])^c
For IPC-2221 external layers: k = 0.048, b = 0.44, c = 0.725
Disclaimer:
These calculations are believed to be correct, but not guaranteed. Use at your own risk!
This Javascript web calculator calculates the trace width for printed circuit boards based on a curve fit to IPC-2221 (formerly IPC-D-275).
Inputs:
| Current | Amps | |
| Thickness |
Optional Inputs:
| Temperature Rise | Deg | |
| Ambient Temperature | Deg | |
| Trace Length |
Results for Internal Layers:
| Required Trace Width | ||
| Resistance | Ohms | |
| Voltage Drop | Volts | |
| Power Loss | Watts |
Results for External Layers in Air:
| Required Trace Width | ||
| Resistance | Ohms | |
| Voltage Drop | Volts | |
| Power Loss | Watts |
Notes:
The trace width is calculated as follows:
First, the Area is calculated:
Area[mils^2] = (Current[Amps]/(k*(Temp_Rise[deg. C])^b))^(1/c)
Then, the Width is calculated:
Width[mils] = Area[mils^2]/(Thickness[oz]*1.378[mils/oz])
For IPC-2221 internal layers: k = 0.024, b = 0.44, c = 0.725
For IPC-2221 external layers: k = 0.048, b = 0.44, c = 0.725
where k, b, and c are constants resulting from curve fitting to the IPC-2221 curves
For geometry diagrams, click on the pictures below.
Disclaimer:
These calculations are believed to be correct, but not guaranteed. Use at your own risk!
Zeev Jabotinsky St,
Bursa, Ramat-Gan, Israel
