Echo State Module (v1)

A Eurorack module designed in KiCad 10.0, built around an Electrosmith Daisy Seed with dual AD5734R quad 14-bit DACs, a PCA9685 PWM LED driver, TL074 op-amps, and 18 Thonkiconn 3.5 mm jacks on a standard shrouded Eurorack power header.

This repository is self-contained: all custom symbol and footprint libraries are vendored under libs/ and wired up through the project-local sym-lib-table / fp-lib-table with ${KIPRJMOD}-relative paths. Clone it and open echo_state_module_v1.kicad_pro — no global library setup required.

Repository layout

Path	Contents
echo_state_module_v1.kicad_pro/_sch/_pcb	The KiCad project, schematic, and board
sym-lib-table, fp-lib-table	Project-local library tables (relative paths)
libs/4ms-kicad-lib/	4ms symbol library + the 8 footprint libraries used (public domain — see UNLICENSE)
libs/emt_personal_kicad_lib.pretty/	Personal footprints used by this board (mouse-bite for panelization)
libs/AD5734RBREZ-REEL7.kicad_sym	AD5734 DAC symbol (via SnapEDA)
pcbway_production/	Gerbers, drill, pick-and-place, and the manufacturing BOM

Bill of materials & sourcing

The manufacturing BOM lives at pcbway_production/echo_state_module_v1.kicad_pcb_bom_manual.csv. Every line item (33 groups) carries a DigiKey link, a datasheet PDF for non-trivial parts, and a sourcing note. The same manufacturer part numbers, DigiKey links, and datasheets are also embedded in the schematic symbol fields (open Tools → Edit Symbol Fields in Eeschema).

A few parts are not stocked at DigiKey and are called out in the BOM's Sourcing_Notes column:

• Daisy Seed — buy direct from Electrosmith or Thonk.
• 3.5 mm jacks (WQP518MA / PJ398SM "Thonkiconn") — Thonk, Befaco, or Oddvolt.
• SW1/SW2 — Tayda only, SKU A-3565 (momentary DPDT 7×7 mm).

Where an original part was unavailable, a drop-in DigiKey-orderable substitute was chosen (e.g. Alpha RV09 pot → Bourns PTV09A; 1N5817 DO-41 → MCC B5817WS SOD-323). The original part numbers are preserved in the BOM's Part Number 2 column.

Library / tooling notes

• KiCad version: 10.0 (version 20260306). Older KiCad will not open these files.
• 3D models are not included. The 4ms footprints reference 3D models via the ${KICAD_4MS_LIBS} environment variable (~160 MB, omitted to keep the repo lean). Everything renders and manufactures fine without them; you just won't get a 3D preview of the 4ms parts. To restore it, clone the full 4ms-kicad-lib and set KICAD_4MS_LIBS to point at it.
• The 4ms library is released into the public domain (see libs/4ms-kicad-lib/UNLICENSE).

License

The design files in this repository are © Eric Trautmann. TODO: choose a license before wide distribution — common choices for open hardware are CERN-OHL-S or CC BY-SA 4.0. Vendored third-party libraries retain their own licenses.