EIT Multiplexer

EIT Multiplexer PCB

EE499 Capstone Project — Low-power analog multiplexer board for Electrical Impedance Tomography (EIT).

Overview

This board drives a 16-channel analog multiplexer (ADG1606) controlled by an RP2040 microcontroller. It is designed for EIT data acquisition, where the multiplexer selects electrode channels to inject current and measure voltage.

Key ICs:

• Raspberry Pi RP2040 — microcontroller
• ADG1606 — 16:1 analog multiplexer
• AP2112K — 5V to 3.3V LDO regulator
• LM27761 — negative voltage converter (for symmetric supply)

Repository Structure

Hardware/         — KiCad project files (.kicad_pro, .kicad_sch, .kicad_pcb)
                    Custom footprint and symbol libraries bundled for portability
Production/
  Gerbers/        — Gerber files + drill files ready for PCB fabrication
  BOM/            — Bill of Materials (CSV and XLSX)
Docs/             — Schematic PDF, assembly drawing, component datasheets

Opening the Design

1. Open KiCad (v7 or later)
2. Open Hardware/EIT_Multiplexer.kicad_pro
3. All custom libraries load automatically via relative paths — no manual configuration needed

Fabrication

Gerber files are in Production/Gerbers/. The board is 2-layer FR4. Upload the contents of that folder (or EIT_Multiplexer-job.gbrjob) to your preferred PCB fab (JLCPCB, PCBWay, OSH Park, etc.).

License

Hardware design files licensed under CERN Open Hardware Licence v2 – Strongly Reciprocal (CERN-OHL-S).