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Cellphone

Open smartphone

The assembly extreme. Almost every line is commodity silicon — the lesson is what NOT to design.

baseline: PinePhone Pro (Pine64) — public schematics
SoC RK3399SRAM 4 GB LPDDR4display 6″ 1440×720battery ~3000 mAh, removable

A phone is where reuse maxes out. Pine64 publishes the schematics; nearly every part is a sealed, solved module you assemble. The descent here teaches the Group-C lesson directly: most of this is zero-NRE assembly, and paying to redesign it is a category error.

7 of 8 parts are reuse — 1 is the slice worth designing. That ratio is the NRE bill. The descent below is how you find it before you pay it.

Exploded

Decompose the product into its stack. Each layer is colour-coded by what it is to the next build.

Glass + 6″ IPS display Common · stable
RK3399S SoC + LPDDR4 Common · cyclic
EG25-G modem + RF Common · stable
RK818 PMIC Opportunity
Removable Li-ion cell Common · stable

Bill of materials

stable ×5 cyclic ×2 Opportunity ×1

Every part is a real, sourced component from the open baseline — no invented part numbers.

RK3399S Rockchip Common · cyclic · refreshes each generation — reuse the current one
Application SoC — 2× Cortex-A72 + 4× A53 @ 1.5 GHz, Mali-T860

Mobile app processor — refreshes on a generation clock. Reuse the current one.

https://wiki.pine64.org/wiki/PinePhone_Pro →
LPDDR4 4 GB + 128 GB eMMC Common · cyclic · refreshes each generation — reuse the current one
Memory — on-package RAM + eMMC, microSD up to 2 TB

Density point refreshes each generation. Reuse.

https://wiki.pine64.org/wiki/PinePhone_Pro →
EG25-G Quectel Common · stable · reuse as-is — zero NRE
Cellular modem — LTE-FDD/TDD + WCDMA + GSM + GNSS; proprietary firmware

A sealed vendor module behind closed firmware — you reuse it, and you would not want to design (or recertify) one. The classic un-paveable part.

https://wiki.pine64.org/wiki/PineModems →
AW-CM256SM AzureWave Common · stable · reuse as-is — zero NRE
WiFi / Bluetooth — 802.11ac + Bluetooth 5.0

Commodity combo module. Reuse.

https://wiki.pine64.org/wiki/PinePhone_Pro →
RK818 Rockchip Opportunity · the slice openWafer designs
Power management — PMIC + battery fuel gauge

The one slice worth touching: fold the PMIC together with an always-on neuromorphic sensor hub, so the A72 cores sleep through wake-word, motion, and context. The energy island.

https://wiki.pine64.org/wiki/PinePhone_Pro →
6″ IPS (Himax controller) Himax Common · stable · reuse as-is — zero NRE
Display — 1440×720 in-cell IPS, Gorilla Glass 4

Commodity panel. Reuse.

https://wiki.pine64.org/wiki/PinePhone_Pro →
IMX258 / OV8858 Sony / OmniVision Common · stable · reuse as-is — zero NRE
Cameras — 13 MP rear · 8 MP front

Standard image sensors. Reuse.

https://wiki.pine64.org/wiki/PinePhone_Pro →
Li-ion (Samsung J7 form) Common · stable · reuse as-is — zero NRE
Battery — ~3000 mAh removable

Commodity removable cell. Reuse.

https://wiki.pine64.org/wiki/PinePhone_Pro →

The slice openWafer designs

A smartphone is the assembly extreme: eight of these nine lines are commodity silicon you reuse without a second thought — even the cellular modem is a sealed vendor module you would never reopen. The lesson is what not to design, not what to. The one slice worth touching is the energy island: fold the PMIC together with an always-on neuromorphic sensor hub so the application cores sleep through wake-word, motion, and context. Pay NRE to redesign a phone and you have misunderstood the system — this is the case that turns every Group A and B into Group C.

Open sources — decomposed and linked, not hosted