# SAME Analog Modular Ecosystem Specification

[![License: CC BY-SA 4.0](https://img.shields.io/badge/Docs-CC%20BY--SA%204.0-lightgrey.svg)](LICENSE.md)
[![License: CERN-OHL-S 2.0+](https://img.shields.io/badge/Hardware-CERN--OHL--S%202.0%2B-blue.svg)](LICENSE.md)
[![License: GPL v3](https://img.shields.io/badge/Code-GPLv3-green.svg)](LICENSE.md)
[![Built with Typst](https://img.shields.io/badge/Built%20with-Typst-008080.svg)](https://typst.app/)

The **SAME Analog Modular Ecosystem** is an open-hardware specification and
architecture for general-purpose analog computing. Designed for technological
sovereignty, 50-year serviceability, and high-precision scientific computation,
SAME bridges classical analog architectures with modern low-noise components and
rigorous topological error compensation.

## Key Features

* **Multi-Tiered Precision:** Defines three distinct operational tiers sharing a
  unified power and backplane infrastructure:
  * **Metrologic Tier:** $0.001\%$ (10 ppm) precision, $90\text{ dB}$ SNR,
    $<0.014\text{ ppm/h}$ drift.
  * **Industrial Tier:** $0.01\%$ (100 ppm) precision, $80\text{ dB}$ SNR,
    $<0.6\text{ ppm/h}$ drift.
  * **Educational Tier:** $0.1\%$ (1000 ppm) precision, $70\text{ dB}$ SNR,
    $<60\text{ ppm/h}$ drift.
* **Robust Mechanical Infrastructure:** Individual $1.2\text{ mm}$ DC01 steel
  shielding cassettes ($4\text{U}$ height, $38.0\text{ mm}$ width) housed in a
  standard $19\text{"}$ rack enclosure with integrated convective ventilation
  and EMI perimeter masking.
* **Unified Power & Clocking:** DB-25 backplane distributing $\pm15.00\text{ V}$
  analog, $\pm5.0\text{ V}$ digital, $\pm10.0000\text{ V}$ Kelvin-sensed
  reference rails, a $90^\circ$ phase-stagger rail, and a system-wide
  $10\text{ MHz}$ OCXO Master Oscillator for Pulse-Width Amplitude Modulation
  (PWAM) compute cores.
* **Executable Specification:** Built natively in Typst, featuring compile-time
  mathematical assertions (`#assert-aeq`) embedded directly alongside typeset
  equations to guarantee zero-copy consistency throughout the text.

## Repository Structure

* [`README.md`](README.md): This file
* [`CONTRIBUTING.md`](CONTRIBUTING.md): Contribution guidelines
* [`CODE-OF-CONDUCT.md`](CODE-OF-CONDUCT.md): Contributors code of conduct
* [`LLM-POLICY.md`](LLM-POLICY.md): LLM usage policy on the repo
* [`LICENSE.md`](LICENSE.md): Comprehensive tri-license legal breakdown
* `LICENSES/`: Actual licenses text
* `*.typ`: Core text of the specification, one file per level 1 heading
* `charts/`: Vector charts built with CeTZ-plot
* `diagrams/`: Vector technical drawings & CAS layouts (CeTZ)
* `tables/`: Modular specification data tables
* `lib/`: Executable Typst helper functions & test harness

## Compiling the Specification

### Prerequisites

* [Typst CLI](https://github.com/typst/typst) (v0.15.1 or newer)
* Fonts: standard system serif ans sans-serif fonts

### Building the PDF

To compile the entire specification from source:

```bash
typst compile preamble.typ specification.pdf
```

To enable live-recompilation during drafting:

```bash
typst watch preample.typ
```

**Note:** During compilation, Typst executes all internal assertions metrology
checks. If any mathematical derivation or parameter in the text strays from
defined engineering tolerances, compilation will halt with an assertion error.

## Licensing

This repository uses a multi-scope licensing model to ensure appropriate legal
coverage across documentation, physical hardware, and executable code:

* **Documentation & Text:** [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/)
* **Hardware & Mechanical Designs:** [CERN-OHL-S-2.0+](https://www.google.com/search?q=https://ohwr.org/cernohl)
* **Code, Libraries & Assertions:** [GPL-3.0-or-later](https://www.google.com/search?q=https://www.gnu.org/licenses/gpl-3.0.html)

See [LICENSE.md](LICENSE.md) or full license texts.

## Author & Contact

**Denis Chevalier**

Email: [perso@denischevalier.fr](mailto:perso@denischevalier.fr)

Copyright © 2026 Denis Chevalier