---
page_id: curated-packaging
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title: Packaging and Chip on Board
slug: curated-packaging
route: /packaging-and-cob
section: reference
access: public
summary: Packaging choices, CoB system structure, and links to pad and production details.
status: published
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home_href: /
md_url: /packaging-and-cob.md
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tags: [wafer-space, knowledge-base, curated]
last_updated: 2026-08-19
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---

# Packaging and Chip on Board

This page is the packaging entry point. It owns packaging choices and the system relation between bare die, wire bonds, CoB PCBs, and motherboards. Detailed pad geometry and production history have separate pages.

## Current summary

The default wafer.space chip-on-board concept uses a small PCB with the die wire-bonded to it. Andrew Wingate described a 14 × 16 mm board with a 70-pin connector, designed to plug into a motherboard. **Confirmed design description, 2025-12-17.** ([archive message](/evidence/designing/cob#message-1450889190068981913); [Discord](https://discord.com/channels/1361349522684510449/1408134567491145728/1450889190068981913))

The shared PCB sources were placed in the `chip-on-board-wire-bonded-pcbs` repository. **Confirmed resource, 2025-11-28.** ([archive message](/evidence/designing/die-sorter#message-1444098695804096585); [Discord](https://discord.com/channels/1361349522684510449/1419841819138854993/1444098695804096585))

CoB compatibility depends on the bond-pad positions and power arrangement. See [CoB Pad Frame and Precheck](/packaging-and-cob/pad-frame-and-precheck). Early production results and defects are kept on [CoB Production History](/packaging-and-cob/production-history).

## Packaging choices

- **Confirmed option.** Bare die and CoB appear as the low-volume forms discussed in the archive. The CoB board and the later motherboard remain separate hardware layers. ([archive message](/evidence/designing/cob#message-1450889190068981913); [Discord](https://discord.com/channels/1361349522684510449/1408134567491145728/1450889190068981913))
- **Proposal and economic opinion, 2026-08-03.** WLCSP was discussed as cheaper at larger quantity but burdened by low-volume setup and assembly cost. No reviewed message announces WLCSP as a wafer.space service. ([archive message](/evidence/i-information/general#message-1533828923555840230); [Discord](https://discord.com/channels/1361349522684510449/1361349523724570941/1533828923555840230))
- **Open question.** The full corpus contains questions about Run 1 die thickness, but no firm numeric answer was found. ([archive message](/evidence/i-information/questions/threads/overall-die-thickness#message-1486974197266645093); [Discord](https://discord.com/channels/1361349522684510449/1486974197266645093/1486974197266645093))

## Board compatibility

Slot-specific power, signal, and pad-coordinate details are maintained on [CoB Pad Frame and Precheck](/packaging-and-cob/pad-frame-and-precheck).

## Related pages

- [CoB Pad Frame and Precheck](/packaging-and-cob/pad-frame-and-precheck)
- [CoB Production History](/packaging-and-cob/production-history)
- [Analog I/O and ESD](/analog-design/io-and-esd)
- [Projects and Designs](/projects-and-designs)
- [wafer.space runs](/runs)

## Sources

- `1444098695804096585` — 2025-11-28T22:52:39.136Z — Andrew Wingate — [archive message](/evidence/designing/die-sorter#message-1444098695804096585); [Discord](https://discord.com/channels/1361349522684510449/1419841819138854993/1444098695804096585) — Shared CoB PCB repository.
- `1450889190068981913` — 2025-12-17T16:35:39.130Z — Andrew Wingate — [archive message](/evidence/designing/cob#message-1450889190068981913); [Discord](https://discord.com/channels/1361349522684510449/1408134567491145728/1450889190068981913) — CoB board and connector overview.
- `1486974197266645093` — 2026-03-27T06:24:35.273Z — asc — [archive message](/evidence/i-information/questions/threads/overall-die-thickness#message-1486974197266645093); [Discord](https://discord.com/channels/1361349522684510449/1486974197266645093/1486974197266645093) — Unanswered die-thickness question.
- `1533828923555840230` — 2026-08-03T13:28:32.539Z — Tim Edwards — [archive message](/evidence/i-information/general#message-1533828923555840230); [Discord](https://discord.com/channels/1361349522684510449/1361349523724570941/1533828923555840230) — WLCSP economics discussion.