Module placement 

Phase 4: Vertical placement within columns.

Places components within each column following electrical convention:

• VCC rail at top (5% from top)
• Supply-connected components (plate loads) extend upward
• Signal path on the horizontal center line (50%)
• Ground-connected components (cathode bias) extend downward
• GND rail at bottom (5% from bottom)

Functions

place_components

Place all components and produce the initial layout.