What is a Single-Layer PCB?

A single-layer PCB (also called single-sided PCB) has electronic circuits on only one side of the board. Though first made in the 1950s, it’s still widely used today.

It’s the simplest type of circuit board, with two common versions:

• Rigid Single-Layer PCBs: Made of fiberglass + copper layer
• Flexible Single-Layer PCBs: Made of polyimide (PI) plastic + copper layer

Note: Flexible versions cost more to make than rigid ones.

What is a Single-Sided Flexible PCB?

It’s the simplest type of bendable circuit board, made by:

1. Printing circuits on one side of a plastic base (usually polyimide)
2. Adding a protective film layer (optional but common)
3. Etching copper traces with acid

Key Features:

• One-sided access: Parts attach only to the top layer
• Holes for pins: Small openings in the base let component legs connect
• Reinforcement: Plastic strips can be added to stiffen areas

Materials: Polyimide (PI), PET plastic, or other flexible plastics.

Why Choose It?
Lowest cost flexible PCB option
Best value when circuits fit on one layer

A single-sided flexible PCB has 3 basic layers:
1. Polyimide Film

• Acts as both base layer and protective cover (like flexible armor)
• Covers both sides of the circuit

2. Copper Circuit Layer

• Middle layer with etched wiring patterns
• Created by chemically “drawing” circuits on copper

3. Adhesive (Glue Layer)

• Bonds the copper circuits to the polyimide film

Key Differences from Rigid PCBs:

• Uses polyimide film instead of rigid solder mask
• May add reinforcement plates (stiffeners) where needed:
  • Materials: FR4 fiberglass, metal sheets, or extra polyimide
  • Attached with: Heat-activated glue or sticky tape
  • Purpose:
    • Strengthens solder joints
    • Prevents bending damage during assembly
    • Improves heat dissipation

Advantages of Single-Sided Flexible PCBs:

1. Simpler & cheaper assembly: Replaces messy wire bundles, cutting build time and costs.
2. Easy design: Simple layout = faster development.
3. Best value: Lowest-cost flexible PCB option.
4. Extreme flexibility: Bend, twist, or fold to fit tight 3D spaces (like electronic origami!).
5. Space saver: Shrinks device size/weight for portable gadgets.
6. Durability boost: Handles vibration, heat, and harsh environments better than rigid boards.
7. Better performance:
   • Cleaner signals
   • Improved heat dissipation
   • Stronger solder joints
8. Fewer errors: Reduces wiring mistakes during manufacturing.
9. Damage-resistant: Stretches or bends without breaking.