How to do wiring for shield board for Arduino Nano in KiCad?

Think of an Arduino Nano shield PCB in KiCad as:

A board with two rows of female headers that match the Nano’s pins, plus whatever parts you want to connect to those pins.

“Wiring” is really just connecting Nano pins (on the schematic) to your parts, then routing those nets on the PCB.

I’ll walk you through it step-by-step.

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1. Decide what the shield should do

Before KiCad:

• Which Nano pins do you need? (D2–D13, A0–A7, 5V, 3V3, GND, VIN…)

• What will you connect?

  • e.g. joystick module: X→A0, Y→A1, SW→D2

  • LEDs on D3/D5

  • I2C connector on A4/A5, etc.

Write this mapping down; you’ll literally implement that in the schematic.

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2. In the schematic: use Nano symbol as the “connector”

Assuming you already have an Arduino Nano symbol (from previous step / library):

1. Create a new KiCad project for the shield.

2. Open Schematic Editor.

3. Place the Arduino Nano symbol

   • This symbol represents the female headers where the Nano will plug in.

   • Its pins D0, D1, 5V, GND… are your interface to the rest of the shield.

4. Add your shield components

   • Connectors (screw terminals, JST…), sensors, joystick module header, LEDs, resistors, etc.

5. Draw wires from Nano pins to your parts
   Example (joystick shield idea):

   • A0 → label net JOY_X → goes to joystick VRx pin

   • A1 → label net JOY_Y → goes to joystick VRy pin

   • D2 → label net JOY_SW → goes to joystick SW pin

   • 5V → to joystick VCC, other 5V stuff

   • GND → to all grounds

   Use net labels instead of long spaghetti lines if it gets messy.

6. Add power symbols & flags

   • Place +5V and GND symbols and connect them to the Nano’s 5V and GND pins (and to your parts).

   • Add a PWR_FLAG symbol on 5V if KiCad complains about “no power source”.

At this stage, your schematic says:

“When a Nano is plugged in, its A0/A1/D2/5V/GND pins will feed these parts on my shield.”

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3. Assign a footprint that matches the Nano header layout

For a shield, the PCB doesn’t carry the Nano itself, it carries the sockets it plugs into. Electrically, though, it’s just a footprint with through-holes in the Nano pattern.

You have two options:

Option A – Use a ready-made Nano footprint

If you imported an Arduino_Nano footprint:

1. In Schematic Editor, open the Nano symbol properties.

2. In the Footprint field, set it to something like:

   • Arduino:Arduino_Nano
     or whatever library/footprint name you added.

3. Save the schematic.

That footprint usually has 2×15 holes spaced correctly; you will solder two 15-pin female headers into those holes and plug the Nano into them.

Option B – Use standard header footprints

If you don’t have a specialized Nano footprint:

1. For the Nano symbol, assign a custom footprint like:

   • An array of 2×15 THT pads, manually created, or

   • Two separate footprints: Pin_Header_Socket_1x15_P2.54mm (left and right rows) combined in one user footprint.

Either way: the pad numbers in the footprint must match the pin numbers in your Nano symbol.

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4. Generate the PCB and place the Nano headers

1. From Schematic Editor, run “Update PCB from Schematic” (the 🎯 icon).

2. KiCad opens/updates the PCB and shows the Nano footprint + your other parts.

Now:

• Place the Nano footprint near one edge of the board so the USB connector can hang over the edge when plugged in.

• Rotate it so that the orientation matches reality:

  • Check: D2, D3, 5V, GND are where you expect compared to a real Nano.

  • Use the 3D viewer to verify: the Nano board / pins should line up with your mental picture of a shield sitting underneath it.

Tip: Once you’re happy with the Nano’s position, lock the footprint (right-click → Lock) so you don’t move it by accident.

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5. Route the traces (“wiring” on the PCB)

Now you turn your schematic wires into copper tracks:

1. In PCB Editor, enable “Highlight Net” and click on A0, A1, etc. to see what they connect to.

2. Use the Route Tracks tool to connect:

   • A0 pad on Nano footprint → pad of the joystick header, resistor, etc.

   • 5V pad on Nano footprint → 5V rail / power traces.

   • GND pads → make a ground pour (copper pour) if you like.

General guidelines:

• Use something like 0.25–0.4 mm track width for signal lines, thicker for power if needed.

• Keep USB side and possible mechanical clearances in mind (don’t put tall parts where the Nano will sit).

• If components will sit under the Nano, check 3D viewer for height conflicts.

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6. Stackable headers vs simple sockets (mechanical note)

Electrically there’s no difference, but mechanically:

• For a simple shield, you’ll typically use two female 1×15 headers.

• If you want to stack another shield on top, you’d use stackable headers (female on top, long male pins going up).
  On the PCB they still solder into the same holes, so the footprint is identical.

Just make sure your BOM lists the correct connector types (female/stackable).

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7. Quick checklist before ordering the PCB

• In the schematic, every Nano pin you actually want is connected to something or intentionally left NC (no connect).

• Nano symbol’s pin numbers match the footprint’s pad numbers (very important).

• In the PCB, the Nano footprint is oriented correctly (5V & GND are where you expect relative to the board edge).

• You have enough clearance for the USB connector and Nano board.

• Two 1×15 female headers in your BOM to plug the Nano in.