Contents
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Microstrip Trace Calculations......................................................................... 6-2
Embedded Microstrip Trace Calculations....................................................... 6-3
Centered Stripline Trace Calculations ............................................................ 6-4
Asymmetric Stripline Trace Calculations ....................................................... 6-5
Dual Stripline Trace Calculations ................................................................... 6-6
Microstrip Calculations................................................................................... 6-8
Embedded Microstrip Calculations................................................................. 6-9
Centered Stripline Calculations ...................................................................... 6-11
Asymmetric Stripline Calculations ................................................................. 6-12
Chapter 7
Autorouting and Autoplacement
Autoroute Menu Items................................................................................................... 7-1
Autoplacement of Parts ................................................................................................. 7-2
Pre-Placing Parts ............................................................................................. 7-2
Understanding How the Autoplacer Works .................................................... 7-2
Running the Autoplacer .................................................................................. 7-3
Controlling the Autoplacer ............................................................................. 7-3
Strategies to Achieve Better Part Placement................................................... 7-5
Understanding How the Autorouter Works .................................................... 7-6
Understanding the Four Fundamental Routing Functions .............................. 7-7
Router Preprocessing ........................................................................ 7-7
Initial Routing................................................................................... 7-7
Rip-up and Retry Routing................................................................. 7-7
Optimization ..................................................................................... 7-8
Autorouting buses ........................................................................................... 7-9
Placing Automatic Test Points ........................................................................ 7-10
Controlling the Routing Functions.................................................................. 7-11
Routing Options: General Tab.......................................................... 7-11
Routing Options: Cost Factors Tab .................................................. 7-12
Routing Options: Rip-Up Tab .......................................................... 7-14
Routing Options: Optimization Tab ................................................. 7-15
Routing Options: Bus Autorouting Tab............................................ 7-16
Strategies to Achieve Better Routing Results ................................................. 7-17