Rotary switch ui

KiCad: Rotary switch UI PCB

This folder contains a small PCB intended to mount:

• An EC11/EC11E-style rotary encoder with push switch
• A 5 mm through-hole common-cathode RGB LED
• 3× current-limit resistors for the LED
• A 1×8 2.54 mm header for wiring to the ESP32-S2 Mini

Project files

• rotary_switch_ui.kicad_pro
• rotary_switch_ui.kicad_sch
• rotary_switch_ui.kicad_pcb

Mechanical reference

The PCB footprint placement is aligned to the OpenSCAD model:

• Encoder center at (0, 0) mm
• LED center at (0, -9.5) mm (from openscad/dimensions.scad led_offset_y)

Recommended footprints (to assign in schematic)

If you open the schematic and run Update PCB from Schematic, assign these footprints first so KiCad can match by reference designator:

• SW1 (encoder): Rotary_Encoder:RotaryEncoder_Alps_EC11E-Switch_Vertical_H20mm
• D1 (LED): LED_THT:LED_D5.0mm-4_RGB
• R1, R2, R3 (resistors): Resistor_SMD:R_0805_2012Metric (or switch to THT if preferred)
• J1 (to ESP32): Connector_PinHeader_2.54mm:PinHeader_1x08_P2.54mm_Vertical

Header pinout (J1)

1. +3V3 (optional; typically not needed for a bare EC11)
2. GND
3. ENC_A (encoder A → ESP32 GPIO34 per docs/wiring.md)
4. ENC_B (encoder B → ESP32 GPIO36)
5. ENC_BTN (push button → ESP32 GPIO37)
6. LED_R_IN (→ R1 → LED_R; ESP32 GPIO4)
7. LED_G_IN (→ R2 → LED_G; ESP32 GPIO5)
8. LED_B_IN (→ R3 → LED_B; ESP32 GPIO6)

Rotary front panel PCB

Small PCB to mount the EC11 encoder, 5 mm RGB LED, and current-limiting resistors for the rotary light switch project. Connects to the ESP32-S2 Mini via a 8-pin header.

Contents

• rotary-front.kicad_pro – KiCad 8 project
• rotary-front.kicad_pcb – Board with footprints placed (encoder, LED, 3× 0805 resistors, 1×8 pin header). No schematic yet; create one and then Update PCB from Schematic.

Schematic (create in Eeschema)

Create a new schematic in this project and add:

Net list (wire to J1)

Use these net names so the PCB matches ../docs/wiring.md:

• Connect encoder pins to ENC_A, ENC_B, ENC_BTN, and GND (check your EC11 datasheet for pin order; Alps EC11E footprint uses A, B, C, S1, S2 — map A/B/S1/S2 to ENC_A/ENC_B/ENC_BTN and GND as appropriate; no VCC is required for the encoder itself).
• Connect LED common cathode to GND; connect R, G, B anodes to the R, G, B nets (i.e. through R1, R2, R3 to the same-named J1 pins). Verify 5 mm RGB pinout (common cathode vs anode, R/G/B order) from your LED datasheet.

Then: Tools → Assign footprint symbols, assign the footprints above, File → Update PCB from Schematic, and in PCB Editor route the nets (or use the existing placement).

PCB layout

• Board size: 50 mm × 35 mm (Edge.Cuts).
• Encoder at top center (shaft position aligned with front-panel 6 mm hole when the board is mounted).
• LED below the encoder (matches led_offset_y = -9.5 mm in the OpenSCAD dimensions).
• J1 at bottom for cable to ESP32.

If your front panel or enclosure differs, move footprints in PCB Editor and adjust Edge.Cuts as needed.

BOM (per board)

Manufacturing

• Single-sided (or two-layer) 1.6 mm FR4; 0.2 mm min trace/space is fine.
• After assembly, mount the PCB behind the 3D-printed front face with the encoder shaft through the 7 mm hole and the LED in the LED cavity; then follow the main assembly for wiring to the ESP32 and PSU.