PCB EMI Shielding Calculator
Calculate electromagnetic shielding effectiveness for PCB designs.
Shielding Analysis:
About PCB EMI Shielding Calculator:
This calculator helps determine the electromagnetic shielding effectiveness for PCB designs based on material properties and design parameters. Essential for PCB design and PCB layout optimization of flex circuits.
Formula Used:
- Total Shielding Effectiveness (SE) = Reflection Loss + Absorption Loss
- Reflection Loss = 168 + 10 * log10(conductivity / (μ0 * f))
- Absorption Loss = 131.4 * thickness * sqrt(f * μ0 * conductivity * permeability)
- Skin Depth = sqrt(2 / (2 * π * f * μ0 * permeability * conductivity))
- Where:
- f = Frequency in Hz
- μ0 = Permeability of free space
- ε0 = Permittivity of free space
- Conductivity = Material conductivity in S/m
- Permeability = Material relative permeability
- Thickness = Shield thickness in meters
Example Calculation:
For a copper shield with:
- Frequency = 1 GHz
- Thickness = 0.1 mm
- Distance = 10 mm
Reflection Loss = 168 + 10 * log10(5.96e7 / (4π * 1e-7 * 1e9)) = 168 + 10 * log10(1.57e-2) = 168 - 13.0 = 155 dB
Absorption Loss = 131.4 * 0.0001 * sqrt(1e9 * 4π * 1e-7 * 5.96e7 * 0.999994) = 131.4 * 0.0001 * sqrt(1.57e-2) = 131.4 * 0.0001 * 0.125 = 0.16425 dB
Total Shielding Effectiveness = 155 + 0.16425 = 155.16425 dB
Skin Depth = sqrt(2 / (2 * π * 1e9 * 4π * 1e-7 * 0.999994 * 5.96e7)) = sqrt(2 / (2 * π * 1e9 * 4π * 1e-7 * 0.999994 * 5.96e7)) = 0.000125 mm
Design Guidelines:
- Higher frequency requires thicker shield
- Thicker shields provide better shielding
- Distance from source affects shielding effectiveness
Professional PCB design and PCB layout require careful consideration of electromagnetic interference (EMI) constraints, especially for flex PCB fabrication. This PCB EMI Shielding Calculator is essential for flex PCB manufacturing, ensuring reliable circuit board design that meets IPC standards. For comprehensive PCB assembly and PCB prototyping, consider using our suite of PCB design tools: the PCB Trace Resistance Calculator for power integrity, PCB Via Size Calculator for multilayer PCB design, and PCB Impedance Calculator for high-speed PCB layout. Advanced PCB manufacturing requires precise differential pair impedance control and proper solder mask expansion. For thermal management in PCB assembly, use our PCB Heat Dissipation Calculator. These PCB design software tools support both rigid and flex PCB manufacturing processes.
Example PCB Design Case:
Consider a flexible PCB design for a wearable device requiring a 90-degree bend. Using polyimide material (common in flex PCB manufacturing) with 0.1mm thickness:
- Input board thickness: 0.1mm
- Select material: Polyimide
- Enter bend angle: 90°
- Choose bend type: Dynamic (for repeated flexing)
The calculator determines a minimum bend radius of 0.6mm for reliable PCB fabrication, ensuring your flex PCB design meets manufacturing requirements and maintains long-term reliability in the final PCB assembly.
