Free Tools for  Board & PCB Designers

Control Impedance  Calculators

• PCB Impedance Calculator

• Microstrip
• Embedded Microstrip
• Symmetric Stripline
• Asymmetric Stripline

• Wire Microstrip
• Wire Stripline
• Edge-Coupled Microstrip
• Edge-Coupled Stripline
• Broad-Coupled Stripline

• Trace Width Calculator
• Internal Trace
• External Trace

• Trace Current Calculator

• Internal Trace
• External Trace

• Trace Resistance

Toolkit of Saturn

http://www.saturnpcb.com/pcb_toolkit.htm

Viewers for PCB Layout Design SoftWare

http://www.cadence.com/products/pcb/Pages/Downloads.aspx

OrCad Light Schematic Capture Tool

http://www.orcad.com/buy/try-orcad-for-free

Gerber Viewer Free Download

http://www.wssi.com/index.php?option=com_content&task=view&id=212&Itemid=213